Custom Supercharger and FVD tuning

Custom Supercharger FVD Tuning..Project GULF -------------------------------------------------------------------------------- Well I thought this is a good time to post on progress on the tuning of my car. FVD is doing the tuning thanks Willey and Mark, I installed the Duramatic software for the parameters and their Flash utility software for installing the modified ECU map. I am hoping to do the first tune at my residence and the final on a dyno, at present the car runs really rich and have plenty of error codes and hunting of the engine itself so getting it to idle is not possible at this time, but I will admit I was nervous running it to operating temp. We are trying to get a way of seeing what the mixture is since I am not reading anything like proper FRA bank 1=99% and 2 =95% and RKAT 1=0% or 2=0% the camshaft positions 1 or 2 also registering 0%. I was expecting initial problems just not the parameters that I really need. I feel I am tuning in the dark but one thing we agree upon is the the injectors are almost twice the size of stock so it must be rich. FVD has shipped my parameters over to the German engineers and will know more what they say when they take a look next week after vacation, boy are they going to have fun when they get back. I have done some educated guessing here on the hunting that with flowed 48# injectors that the error code #115 MAF "out of range" is showing the ECU is trying to compensate but can not. I am from old school tuning and not familiar with this stuff so feel welcome to input your ideas they are appreciated. ERROR CODES: 115 MAF out of range 13 heating power ahead of cat bank 1 62 damaging to cat 63 cyl 1 misfire damamging to cat 65 cyl 3 damaging to cat 67 cyl 5 misfire damaging to cat. I have some videos please excuse the quality, also a data file of many parameters of engine running log file (xls format) for the hardcore anyone want to try to graph it?. I will add as tune progresses. Located at: http://www.webbspot.com/Porsche/fvdvideo.html

MAF out of range - on American cars, which I assume is the same as the 996, if you mixed bigger injectors without calibrating the MAF, the car would have big problems idling misfire codes- obviously from being so rich causing plug fouling I am surprised the engine runs with 2 X's the injector size. Have you ever thought of contacting Evolution Motorsports and see if you could get their software and hardware for a baseline tune? After, you could do a custom tune. GIAC supplies Evo software. Keep us posted on the progress!

I agree on you on the MAF it is a new MAF and would think it would not need any calibration as long as the A/F mix was in tolerance? How would you if so. Regarding the misconception of Garrett and EVO the reason I choose FvD was because Garrett will not supply a base map and was told to talk with EVO then they gave me the run around to talk with Garrett, so I will not do business with either because of the "M" word..

Quotes source post: 4596905

+1 (highlighted area). On my S/C 351W '89 Mustang I moved-up from stock 19's to 48's and had to get a new MAS that was larger for more air-flow and supported the injectors. It is a PRO-FLOW unit and if I change the injector size I have to get it adjusted again. I have heard of adjustable ones but you need special software etc. to do the changes, something you find at dyno places.

Quotes source post: 4596938

My 2 cents: From my limited understanding of EFI, the A/F will be off because your pulse width and duration are the same given by the computer, but now you have injectors that flow more fuel. It is probably going haywire trying to compensate and lean. Your best bet would be to post this question in the 930 (911 turbo) forum, there are some guys who really know EFI quite well. The only issue is, they probably wont know about the camshaft timing data. I got the same run around as you did. I became slightly discouraged now with turboing my 996, I feel these tuners are being secretive.

Quotes source post: 4597026

The Pro-Flow gave a friend of mine big time headaches, his car never idled because the PF's trick the computer istead of being calibrated. I guess you had good luck.

If you're doing any of this without a wide band oxygen sensor you're looking for trouble. Step #1 in this is to get your AFR's in a reasonable range.

In the stock engine, your map tables correspond (among other things) to the input from your MAF. Now that you have increased the amount of air passing by the MAF, your computer is opening up the injectors to come up to proper balance. However, off boost, all the air reported by the MAF IS NOT going into the engine. Therefore, you run rich and your O2 sensors try to pull back the fuel, etc, etc. At WOT, without limiting the current to the MAF, you will exceed the mechanical limits of the MAF and it will eventually burnout. Having no idea what turning has been done on the mapping, you first need to get the MAF's reading down to a level around 4.5 g/s at idle. This should get your fuel/air mixture within a managable level. Probably the best way to do this is to install a resister inline on the cable to the MAF. In effect, you are telling the computer that you have less air entering the engine. Even with the stock mappings, the engine should idle smoothly as the O2 sensors will properly manage the fuel. Now, during off vacuum operation, because you reduced the current to the MAF, the engine is getting more air than the MAF is reporting to the computer and you are running lean. This is where the fuel maps come into play and must be adjusted to higher levels based what the lower MAF signal is sending the computer. Remapping should be quite easy for the tuner if he knows the actual air flow to the intake, both on and off boost.

'99 - You say the motor is not receiving all of the metered air. Doesnt the BOV recirculate the metered air? Your S/C kit came with a bigger MAF sensor? Why I ask, is I have a friend putting 550HP to wheels using the stock '87 C3.2 MAF. I wouldnt think that the 996 meter is maxed with the S/C. And you say tricking the MAF, I have seen this cause mad problems on a friends car. The car made excellent power at WOT but never idled properly.

Quotes source post: 4597748

No one said anything about a bigger MAF. On vacuum, not all the air metered by the MAF is entering the intake. The fuel metering is dependent on the signal it receives from various sensors, including the MAF. All the remapping is doing is changing the amount of fuel injected based on lower input from the MAF. Since you cannot increase the maximum amount of current to the MAF without burning it out, the signal to the computer will remain the same (by way of resister control). What the programmer does is simply calculate what the actual air flow rate is with the SC and adjusts the mappong. If the SC doubles the actual amount of air into the engine, then the mapping would be adjusted to double the amount of fuel based on the same signal. Example. Stock engine MAF signal of 50 g/s injects 1 pound of fuel SC engine MAF signal of 50 g/s injects 2 pounds of fuel

Quotes source post: 4597792

Sure, the mapping I understand completely, it is the MAF metering I am not following. If I recall, the air is recirculated back through the inlet of the S/C from the BOV. This causes less air to enter the MAF and balances out the metered air. This principle works on Fords and I assume on the 996 since the MAF is before the S/C?. On a side note, LS-X motors air is metered after the S/C, the boost can be dumped to atmosphere. By tricking the MAF, I would think all is fine and dandy until you start reaching boost. Then the resistor would limit "actual" airflow sent to the computer by the MAF signal causing a lean condition, the engine is actually injesting more air than it is reading. I may be missing something though.

Quotes source post: 4597915

Yes the off boost air is circulated outside the intake but the MAF is still drawing more air than is getting to the intake, so you need to calibrate the MAF signal. The resister DOES NOT restrict airflow, only the current reported to the computer. As I mentioned in the previous post, you MUST limit the maximum signal from the MAF or risk burning it out. This is the ONLY purpose of the inline resister. It is the programming of the computer that determines what to do with the "incorrect " MAF signal. The stock program would make the engine run lean, but the modified program would be adjusted so that it injects the proper amount of fuel. When the computer is programed at the factory, it has already been determined what the airflow ACTUALLY is at various rpm's and other conditions. From that starting point, the computer is programmed to inject a specific amount of fuel based on that airflow. The linear MAF signal is just the vehicle that the computer uses to measure airflow and temp, but in no way controls airflow. The progammer knows that the MAF reading will be "X" when the ACTUAL airflow is "Y" and tells the computer to injected "XY" amount of fuel. The bottom line is, the computer is in control and is simply receiving signals from the sensors. The computer programming is what determines what to do with these signals.

I worded it wrong, I know the resistor doesnt limit airflow of the MAF, it limits or tricks the signal.

Quotes source post: 4597613

I agree I feel I am walking on ice, I was depending on the FRA and RKAT for some readings on A/F but No-Go. I am thinking of a autometer.

1999, Tippy, If at idle the engine is not processing any more air flow then stock, so why would any changes be needed to the MAF. Would it not just run rich and still get the MAF error #115 "code out of limits".

Quotes source post: 4598361

Because the MAF determines engine load, airflow and air temp. Since you are sucking much more air past the MAF that the stock parameters allow, you MUST reduce the voltage produced by the increased airflow or you will get a code Hook up a 560 ohm resister inline and see if that drops the flow down to 4.5 g/s at idle..

no mods are needed to the maf, new program should: change ignition timing, fuel delivery, prevent detonation and fuel starvation above 3000k...Agreed, The new map is supposed to get A/F within operating range... be careful when running without the new programm.

Quotes source post: 4598479

WRONG! Unless your goal is to quickly burn up the MAF.

Quotes source post: 4598499

Mother setup is not any different than Evo and they dont touch the MAF, just injectors and programming

Quotes source post: 4598515

Yes they do. You must reduce the amount of airflow that the MAF reads by either using a resister or modifying the flow of air through the tube.

Why would the MAF burnout, or what causes it to burnout? I do not follow, not saying you are wrong, just never heard of this. Curious what raises the voltage, the computer? And why would it raise the voltage, it knows no different that a S/C is on it or not, it simply has air flow through it.

Quotes source post: 4598597

What would happen if you increased the amperage on 14 gauge wire in your home from 15 to 20?

Quotes source post: 4598607

Meltdown. I understand why it will burn up, trying to understand what causes the voltage to increase. Only thing he has changed is the injectors so far. Is the computer raising the voltage of the MAF to compensate for the bigger injectors?

Quotes source post: 4598597

Cut and paste from a site. The MAF sends Voltage (0-5v) directly to the ECU. Using various other sensors (like TPS, and Tach) the ECU adjusts the injector pulses, timing advance/retard depending on the state of the engine. MAF voltage alone directly affects the Air/Fuel Ratio the ECU produces. when a Piggyback Fuel Computer is used (S-AFC2, V-AFC2, Neo, Emanage, UTEC, etc) it intercepts Voltage from the MAF, and modifies that Voltage going back into the ECU (according to your own Fuel correction settings). That's is why a MAF is THAT important. When a MAF fails the voltage output can become erratic. when a MAF is dead the engine cannot Rev past 2500 rpms. I am assuming the resistor 1999 is referring to lowers the voltage for idle and allows more room (V) for extra airflow under boost with proper mapping.

Quotes source post: 4598664

The MAF must receive current to keep the wire a specific temperature. Because of the increased airflow, this current is maintained at it's maximum for greater periods of time and causes meltdown. Just like if you maintained a draw of 15 amps on a 15 amp circuit. It is only a matter of a short time before the circuit breaker pops.

I read many moons ago that the wire voltage was maintained at a given number, it did not fluctuate. It was the delta of cooling of the wire that determined airflow, never read it raised the temp to compensate. My interpretation was, the cooler the wire was from a given point, the more air had passed over the heated wire. My point is, if you raise the voltage to raise the temp of wire, how does it know the airflow difference?

Quotes source post: 4598544

What did evo do to there kit, did they add a resistor or change the flow path, changed to another range of MAF?

Quotes source post: 4598766

The maf works like this. There is a thermistor as a sensor, it is used to be heated, at a set (constant) temp. As air flows by it, it will cool... the computer tries to heat it up more since it wants it at constant temp. The voltage that is required to heat up the thermistor is proportional to the amout of air that tries to cool it. The varying heating up and cooling down is the signal of the airflow.

Since this is a project lets test it. Which wire to hook up the 560 ohm resistor inline with? There are (4) 2 red and cannot remember the other two to the MAF. How can I measure the 4.5 g/s whatever that means at idle with the durametric? I should know immediatley on start up if there is any improvment.

The thermister maintains a constant temperature relative to the IAT. If the IAT is higher, the current of the thermister is increased.

http://en.wikipedia.org/wiki/MAF_sensor

Quotes source post: 4598826

Ding, Ding...that is the magic answer I was looking for. Ok, that was what '99 was referring to as the MAF wire burning up.

Quotes source post: 4598716

That answers the other question I had. See, this is different technology than how the American cars do it once you have exceeded the capability of the MAF. You simply got a bgger CFM one that matched the injector size. Good stuff.

Quotes source post: 4599142

Missed that one Tippy

Curious which establishes the MAF ERROR is it the ECU or the MAF? Is it voltage, amperage or resistance it looks at? If the MAF/ECU has a operating range of 5V and the engine at idle with regular CFM flow *no boost" why are the data numbers showing rpm between 500-3000 and being within that range?

the maf range is 0-5v, at 2.5K rpm you are already past mid scale of the maf. This is what 1999 is saying. it looks like you need to lower that signal so it will match 0-redline rpm = 0-5v. I have to open up my air intake and see if evo have baffled the maf somehow so it will see lesser air flow, maybe this is how they done it instead of the resistor.

Quotes source post: 4599941

Mother, ok that sounds weird, I honestly think you are beyond this board. Like I posted earlier, there are a lot of EFI tuners on the 911 turbo board. There is a bunch of guys who tune by laptops. They tune by the 02 sensor and EGT from what I have read. '99 and redridge probably will throw in more theories but I think it is time to haul the enigne to a dyno and have GIAC professionally tune. There isnt any tuners on this board, or at least I have never heard anyone talking on that level. If there is, they should of stepped up by now. Everytime this is discussed, I think of this time about 12 years ago when this professional drag racer (leaving his name out) here thought he could lean the motor to get more power. He just learned DFI (Digital Fuel Injection) and typed in a few keystrokes on the keyboard and on his next pass, bam!!!! 1800hp motor blown into bits. Hope this doesnt happen to you.

Quotes source post: 4600001

I would appreciate that redridge (Is yours supercharged?) EVO says that the system can returned to stock but if they spliced into the harness for the resistor then that differs from what they advertise. If there is a resistor which color wire is it hooked up to?

Tippy, Having this thread and input from you and others helps the person making these mods in the future. I agree I have blown my fare share of engines in the past and am trying to approch this with some caution. FVD is doing my tuning as we speak there german engineers will be back Monday and we will go from there slowly as they put it. What's nice is they take your suggestions and listen and I like that, rather then we know it all. The first step is get it to idle at my house so I can leak check etc etc... Then when ready take it to a dyno for the fine tuning it is costly for dyno runs $100 an hour or so.

Sent you a PM

Quotes source post: 4600307

Replied to PM

Quotes source post: 4599941

Don't forget that airlfow is dependant on throttle position. You can a have high MAF signal at low rpm as well as a low signal at high rpm depending on what you throttle is doing.

I really don't believe that burning out the MAF is a concern. Maxing out the voltage (due to high airflow) is a concern but not because of buring the wire out. The concern is that you are the uppper end of a sensors range (and possibly beyond it). This means that you're supplying more air than the ECU knows how to compensate for and you will either throw a code or start running lean. The current through the MAF wire is limited by it's intrinsic resitance and the maximum 5V that will be supplied to it. Granted, if you let it sit a max voltage and therefor max current it will have a shorter life (as 1999 pointed out), but this is a secondary problem in comparison to the potential for running lean and destroying your engine. 1999's suggestion of placing a resistor in the circuit will lower the current should work to prevent that problem but I just don't think it's that big of an issue. My additional concern with this method is that you're changing the output from the MAF which would then have to be adjusted for in the EFI tuning. If you're maxing out the maf sensor I'd change sensors.

According to the readings I am not maxing out the voltage but they seem erroneous with low throtttle applied. I suppose that if the ECU is calibrated to receive so much fuel at a given votage and throttle angle then it should run either rich or lean depending, but it does neither it hunts.

Mother. On your chart, what are your airflow figures representing?

What conditions was this data collected under? I'm assuming this is just ideling, or are you blipping the throttle? Your data is all over the place as you pointed out. If this is just at idle, I'd want to know why your throttle position is varying so much. For some perspective, when plot my MAF vs. rpm (100% throttle) I get nearly a perfect line. Is your rpm hunting like this at idle?

Quotes source post: 4603210

Not sure what you mean but they do represent a hunting conditon. For instance at RPM 1,448 (line 4) MAFlow increases as the MAF voltage decreases? Have a look.

Quotes source post: 4603431

My goal is to get it to idle, at present I have to (gently apply) the throttle to keep it running and when it kinda stabilizes above 1000 RPM it starts to hunt. I cannot check for vaccum leaks being I am the only one here so I cannot do both.

Quotes source post: 4603795

I am asking whether the MAF numbers are grams per second or pounds per hour, or what other scale they represent. And what is the difference between the F7 and F30 MAF numbers. I'm assuming F30 is in volts?

Quotes source post: 4603823

F30 is in Volts not sure of the F7 I will try to find out. I am using Durametric software.

I'm guessing kg/hr. Put a resister inline as I suggested earlier. Cut the MAF cable white wire (pin #5) and splice back together with the resister inline. This will immediately reduce reported air flow and drop the amount of fuel to the engine. Disconnect battery cable for a few minutes and start her up. You will need this resister regardless of what the cause of the rough idle is, anyway. In closed loop, your engine will balance the F/A ratio with no problem. However, until you get your remapping done, WOT operation will be running lean.

Quotes source post: 4603993

Thanks, I give it a try tomorow. Durametric reply for the MAF reading is this Reply: Durametric The parameters that are available are not defined by us. They are defined by Porsche and match the factory service manual and Porsche training manuals. We can only represent the values that the cars computer is capable of displaying.

Mother, It would be trivial for FVD to copy the HFM5 MAF characteristic curve and the OBD2 plausibility checks over from a 996TT to the 996 ECU. The 996TT MAF linearization curve has a measurement range from 126.2 kg/h upto 1598.7 kg/h which will cover your supercharger installation. Then all you will need to buy is a tube and MAF sensor from a TT. The MAF is the primary load sensor so trying to do this any other way (i.e. tricking the ECU) should be avoided if at all possible, which in this case it is!

Quotes source post: 4604327

Sorry Jason, that will not work. His problem is not with the accuracy of the MAF but with the fact that the amount of actual air running past it (which is being measured properly now) is not matching the amount of air entering the engine while off boost. Remember, his sensor is before the compressor. The fix I suggested is standard practice and costs less than $1.00 to complete.

Quotes source post: 4604194

Your goal is to get your MAF reading to about 22 kg/hr at idle. This should keep the fuel/air ratio well within managable range for the O2 sesnors. BTW: What year is your car? I can't remember.

Quotes source post: 4604438

Just so I can understand what you're suggesting, are you saying that his MAF is reading accurately and that the supercharger has roughly tripled his airflow at idle? Since the idle characteristics of the ECU are looking for lower airflows it's hunting to find a good idle? S.

Quotes source post: 4604773

Since the airflow and temperature is measured BEFORE the compressor and the majority of this air does NOT enter the intake while off boost, the MAF is over reporting airflow to the engine, even tho it it accurately reporting airflow it sees. Therefore, if nothing is done to properly calibrate the MAF to equal the air to the engine, you will ALWAYS run rich while off boost.

Quotes source post: 4604773

thats how I see it.... but whats weird is its not under boost, and the maf should be able to read the current flow

Quotes source post: 4604823

Remember that the intake system (before throttlebody) is a living, breathing system which both inhales and exhales. If it was an true intake system only at the point of air measurement, measurment would be more accurate, but the recirrculating compressed air would very quickly reach unmanageble heat levels.

I can vouch for the centrifugal S/C's, they put out a huge amount of air at idle, just like '99 said. You have to dump it to atmsophere or reroute it through the inlet of the S/C. This is what he is talking about. My 0.02. Putting a resistor on at this current time is a not needed. Although it would work once properly tuned to the new "resistance". But currently, it is at stock settings. WOT: The engine will not see WOT until FVD tunes it. MAF "burnout" will not be an issue since the engine will not take it the full WOT air. Idle: If the air is recirculated through the inlet from the BOV, there will not be any excessive air above the requirement of idle drawn through the MAF since it is simply reintroduced to the inlet of the S/C. I have a hard time explaining this but this is how it works on Mustangs for sure.

Quotes source post: 4604854

Since you are still working on your degree, you should be in a "learning" mode rather than trying to "teach" things you do not understand. I built by first boosted engine long before you were even born. With Mother's setup, you MUST calibrate the MAF to reflect the actual air getting to the engine, whether you use a resister or some other method such as allowing unmetered air to pass into the system. To suggest that simply reprogramming the computer will somehow eliminate the problem, is also wrong as the range of the MAF is too narrow and you WILL burn it out. An inline resister is no different than buying a MAF that has the correct calibration to begin with. The only difference between hot wire MAF's is the rating of the resisters it is made with. You could get the same results by replaing the resister INSIDE the MAF, but I suspect that that is a task that few people are capable of doing. The fact that airflow is cirrculated while off boost does not eliminate continued and excess airflow past the MAF. Review your Physic books for further details. Finally, I have no idea what you are saying about the engine not seeing WOT until the tuning is done. This, also is not true. If your intention is to take such a simply concept and make it complex, you seem to be succeeding. This is a simple and long standing calibration that has been done since resister based sensors began measuring intake flow.

Quotes source post: 4604501

2000 996, The wire I have is WHT/BLk as signal wire and the R/Violet as 5 Voltage.?

Hey, I am not claiming to know more than you, but I have been around some impressive boosted FI'd cars. Mother is not going to run WOT with just his injectors changed and no comp upgrade. So how is the computer going to "burnout" the wire? Simply wont be enough airflow. At idle, I can see what you are talking about because you will be tricking the computer into thinking there is not much airflow reducing the fuel, I gotcha' on that. My degree is in Business by the way, my mechanics degree is from the school of hard knocks. By the way, I was boosting blow through carbs (above 20 PSI) back in '96 before the aftermarket world caught on, I was only 16. If you want to talk about it, PM.

I am bowing out of this thread, good luck Mother on the S/C!!! Keep us posted and relay the info from FVD. I would love to turbo my car someday, got to get the FI side panned out. The turbo fabrication side is the easy part.

Quotes source post: 4605080

It would be the white/black. This wire should have no voltage with key on and engine not running. The oither 2 NON ground wires will have 5 volts and 12 - 14 volts. Wire #5. BTW: You may get a smoother idle right off the bat by starting the car without the MAF connected as the computer will default to the maps.

Quotes source post: 4605144

Sounds like fun project Tippy good luck. I will post progress so check back.

Quotes source post: 4605159

Makes sense I'll give it a try later. I have not tried diconnecting the MAF since I had my injectors reflowed. I should know soon after startup on results as you said then get back to FVD on maps and take it from there.

Quotes source posts: 4604982, 4604982

I'll be the first to admit that I have zero experience with supercharged engines but how on earth can a resistor modded MAF account for the effects from a blowoff or diverter valve? The compressor is pulling air through the MAF so the MAF is aware of it. The only questions are will the measured airflow value get clipped by the sensor & ECU and what happens when the throttle closes and air is recirculated? The 996 egas MAF has a measurement range of 47.3 kg/h to 1285.0 kg/h. So you might throw a CEL if the diagnostic plausibility checks are left untouched. If air is diverted around the throttle-body isn't the usual (i.e Bosch) method that corrects for this involve adding a pressure sensor? How can reducing the MAF value (installing a resistor) account for this?

Quotes source post: 4607733

All the resister is doing is reducing the voltage that is reported to the computer to reflect the fact that not all the air is goiing to the engine during off boost operation. Therefore, idle and most off boost operation, the S/C engine will run pretty close to normal on the stock program. At WOT, all the air passing by the MAF is getting to the engine and the resister is now under reporting the voltage to the computer and the fact that you are no longer running a 3.4 engine but one that is much bigger because of compression. This is where the remapping comes in. The tuner now changes the paramters of the maps to reflect for the fact that the MAF signal is lower and cylinders are bigger. As I explained before, it does not matter what the absolute MAF reading is as long as it changes predictably with airflow. The new program will be completed to reflect what fuelng is required based on throtte position and MAF signal and other parameters. i.e. the stock program may have assumed that there was 200 g/s of air getting to the engine at WOT when the MAF signal was 4.8 volts. Because of the supercharger, the program would be changed to think that their was 200 g/s of air when the voltages was only 4.7 and fueling would be adjusted accordingly. Don't let the reported "airflow" range of a MAF confuse you. The difference between a MAF for a 996 and a TT is NOT the amount of airflow it reads or the range of voltage that is generates. The amount of airflow is a calculation done by the computer based on voltage only.

Quotes source post: 4607733

In a closed loop system regarding the BOV or recirculating valve once the metered air passes through the MAF (with resistor or not) and calculated by the ECU and any excess air is dumped during vaccum via BOV back "after" the MAF sees no change since it has already been measured everything remains moot. I think I confused myself.

I put some thought into this and take it how you want, how about this? First things first, put an EGT gauge on it!!! Put the resistor on the MAF, now the motor thinks it is taking in less air leaning the idle mixture. Now, put a FMU (fuel management unit) after the fuel regulator. Adjust idle mixture until engine runs clean and lean until EGT barely raises over rich condition. Last bring up RPM and make sure EGT doesnt pass say a few hundred degrees past idle @ rich. I dont know what the proper EGT temp should be? Temps can vary depending from point of exhaust flow. FMU's can be adjusted to reflect boost increase , example 1:1, 1:2, and up. Now for every pound of boost, you can get a ratio of fuel pressure. This is how we did it, no maps needed changing, used the stock timing and fuel maps, just tricked it with a lot of fuel pressure under boost.

Of course, once the FVD programming comes in, take off the FMU. I would have an EGT on any S/C'd car, it is a must.

I had to get back into this thread. I snapped when '99 said to use a resistor, this will take care of the MAF. I was amazed that an engine would even run with the "wrong" injector size, now I know it will. Since it does, and the reisistor will work, I thought why not control the fuel by a FMU and adjustable fuel pressure regulator using an EGT? We done this with Mustangs many a times in the early days except we had a MAF that matched the injectors and CFM capabilities of the S/C.

Quotes source posts: 4608116, 4608116, 4608116

The problem with inserting a resistor (fixed function) is that it will modify the reported flow at all times and not just during off-boost. You're trading one problem for another that requires more work to fix properly. And even then, if you're not measuring airflow you'll be screwed eventually as things age or if problems arise and something else can't compensate. There is no reason to hack the system up in this way if you have complete access to the ECU sensor calibration, which is something FVD does. Actually with the torque based ME7 it does matter, the MAF is the primary load sensor. The difference between the MAF & housing for 996 and 996TT is that the different measurement ranges produce different voltage levels corresponding to different flow levels. The chart that I posted was created from the actual calibration data from 996 and 996TT ECUs that I disassembled. The sensor does actually measure airflow.

Quotes source post: 4611209

So, installing a resister in the TT MAF is the right solution, yet, somehow installing it "outside" the MAF housing is not? The MAF does absolutley nothing to control fuel, load, or anything else. The computer determines what to do with the signal. Example: The MAF has a limit of 5 volts. By not calibrating it, you reach the 5 volts at 90% throttle and 6000 rpm after you install an S/C. At this point the program (stock or modified) is responding to the 5 volts by dumping fuel, etc. What tells it to add more fuel when the throttle hits 100% and rpms hit redline? Can the MAF's voltage increase from 5 volts or is it some miracle that automatically allows the computer to "guess" what the fuel trim should be for the top 10% range? It's not a complex issuue. There is no way to substantially increase airflow to an engine and provide the correct fuel mixture using a stock MAF without somehow modifying the signal of the MAF. If you modified the housing of the MAF, you have modified the MAF reading.

Interesting reading, I have told FVD to hold on the tune temporaily, I found some leakage issues. A torn aftercooler reducer (has been ordered along with T-Clamps) and the intake has to be refabbed which is almost completed. I will get new readings when running again shortly after parts arrive.

Quotes source post: 4613987

I used a sewer pipe reducer from Home Depot for the inlet side of the S/C. A few dollars and it worked for years. It connected the daddy sized K&N cone (which I dont recommend) filter to the inlet of the S/C. T-bolt clamps are must, I was popping off the worm gear clamps under high boost on the discharge tube side.

Well the car runs 100% better and does idle, no hunting or smoke with new intake and the $1.00 resistor, but still seems alittle rough with no misfires indicated. I cannot remember, but I think I had a error message with one of the O2's and will re check later just wanted to tell eveyone that helped thank you and GOOD JOB! The new info was sent to FVD and we will see what they think. 1999 not sure which O2 voltages after cats since there only seemed to be the one for right and left banks (Conv) but seemed one bank running very lean hope this is what you where talking about, if I missed something let me know I can get more data. Attached in 2 parts are the new numbers that will lend some indication of what the engine is doing plus new crappy video and Excel spead sheet at: http://www.webbspot.com/Porsche/fvdvideo.html I also had 2 error/fault codes: 1. P0134 code 10 - O2 sensor ahead of Cat conv. 2. PO1115 code 13 -Heating power O2 s ahead of cat bank 1 I think I need to check my O2 sensor connection.

What size resister did you use?

1999, A 560K resistor was used inline with wht/blue wire. Do the MAF Volt readings seem closer to what they should be at idle? Still not sure of A/F at this point. On reading "Sensor-signal period ah. of cat. c. bank 1" (not on graph) reads 0.00 resistance which I will clean connector today and see error stays cleared.

Quotes source post: 4649490

Your after cat O2 sensors are reading too high (very rich) on both banks at idle. You need to get your MAF reading down closer to 1. Your tuning will get you there. Take it out for a spin and while watching the after cat O2 sensors, see what they read at WOT. If they read 88 volts or higher, you are more than safe as far as F/A ratio goes.

Still have concerns, I cleaned connectors on bank 1 (before/after) cats and you can see my values have now changed? To me looks like a lean conditon? The before data above showed a rich conditon, "after cat" now it is lean and before still reads about the same as before? Did I just loose 2 O2's ? F5/F7 bank 1 - F9/F10 Bank 2

Assuming you data is accurate, you have a problem. He or some possabilities: Assuming Bank 1 readings are accurate: Leaking injector(s) bank 2 Assuming Bank 2 readings are accurate: - Exhaust leak on bank 1 before sensors - Vacuum leak effecting bank 1 only - clogged injector(s) on bank 1 OR Every reading of your before cat sensor (bank 2) show RICH, which means it is not functioning???? If it is not fluctuating high to low every second or so, the sensor it not working. If the computer sees that the sensor is at the voltage you show, it should be cutting off fuel to that bank. However, your bank 1 sensor is also consistantly low. You need to verify that the before cats sensors are going from high to low by watching them while idling. MAKE SURE your engine is warmed up and in CLOSED LOOP. They do not function to control fueling in open loop.

What do you mean open/closed loop? I'll add fuel to the fire here Are the O2 resistance values in data of the actual O2 sensors? If so, I would think these values should change constantly if the sensors are working and one in bank 1 is reading Zero? I think that bank 2 readings are correct because of fault code 1115 not clearing which is a bank 1 problem "O2 heater". All values you have seen are of car warmed up.

I just can not get past the Fault Code 1115, so I ordered a new O2 sensor for piece of mind. Let you know my findings. I think both banks should read about the same weather the left one is lean or right bank is rich. My intake (Distributor) has all new O-Rings and new exhaust gaskets where added for my exhaust so I am ruling that out also for now. I can also move the new O2 from one side to the other to see which one is not reporting correctly. 1999 is assume by closed loop that the computer is running off real sensor paratmeters and not computer set points when cold?

Quotes source post: 4652562

Yes. In closed loop, the before cat sensors should be oscillating high to low. If not, sensor is bad.

Ok, an update the new (bank 1 O2 before cat) sensor has be installed and car runs better and Error Code 1115 I had previously has cleared. It seems rich at idle but leaner once warm and the numbers (O2 V) seem better, but lean after cats? Note: On image first votages are of bank 1. Feeling more I confindent drove it down street at idle but have a "CLICKING" noise that seems to be comming from wheels on both sides, I had redone the brakes with new pads so I still am not ready for Dyno I made a video of the sound tell me what you think: http://www.webbspot.com/Porsche/video/clicking.3gp Or go hear also for both spread sheet and video. http://www.webbspot.com/Porsche/fvdvideo.html

First of all, you can tell absolutely nothing from a snapshot of the primary O2 sensors at idle. Secondly, you are not running lean if the secondary sensor numbers are to be believed. Thirdly, you still need to lower your MAF voltage Doubleup the size of the resister. Then take a look at the after cat sensor readings at WOT at maybe 5000 rpm.

Quotes source post: 4698576

What voltage SHOULD I have at idle for the MAF that would also produce the proper voltage at WOT? The reason for installing the new O2 was because of the error 1115 showing up as lean condition on earlier graph on this page. The rear "clicking Noise" is prohibiting me from WOT runs as noted in the video at above link.

Quotes source post: 4698786

Take a look at what the flow is of the MAF. You need to keep it below .95 lbs/min at an idle of 800. Slightly higher for higher idle and lower for lower idle. Probably closer to a 1.30 voltage from the MAF. I have no idea what your spreadsheet is showing as the voltage is all over the place.

Quotes source post: 4699196

In above data the MAF voltage seems pretty good around 1.3 - 1.4V. I will recheck the flow I can't remember off hand.

Quotes source post: 4699196

These numbers do change alittle: @ 770 RPM Hot film MAF = 19KG/HR Units if converteed to LBS/Min = 7 I'm using Durametric not sure where you are getting that number? MAF V = 1.28 - 1.36V fluctuates some

Quotes source post: 4702264

Your calculation is wrong. 19 kg/hr is the same as 0.70 lb/min. Therefore, your flow reading is fine.

At Trig I was even worse. I think my next step is to fix my noisey rear end and off to the dyno. If I need to when testing I can drop another resistor in there between runs and monitor. Thanks 1999 and will post results as I go.

Quotes source post: 4702994

GAS-X may help with that probelm!

Quotes source post: 4702994

Based on your reported MAF flow, you can skip adding another resister.

Quotes source post: 4703020

Yea, those cheap corks don't seem to hold.

Update: Long day did some data testing for 1/2 around town and freeway from idle to WOT. Well after just finishing 5.5 hrs for replacing my sc/main drive belt which I schredded at idle, but luckily at my house (I think I found the problem a sharp edge on bracket wut will see) I also found out a couple of things one is you run out of freeway real fast in a 3-4 gear WOT run and that you hear all kind of strange smells and a buzzing noise comming from the eng compartment and it went away hummm. Anyway here is some data, but am concerned that I lost MAF voltage at WOT run or should I say at 6,200 rpm my voltage when from 4.6 to .99 there after and never changed ( Note line 492 in data sheet under Maf voltage column CG) regardless of rpm change? Here is link to data sheet: http://www.webbspot.com/Porsche/fvdvideo.html click 1/2 hour data run.

Check your splice on the MAF cable.

excellent progress Mother... youve come a long way! Your MAF might be toast.

Boy after re reading my post I must be tired I did not unerstand it LOL. I'll rescan tomorow and see if the voltage is back and recheck splice and hopefuly spell better. The data is for FVD and they wanted an hour but laptop battery only lasted 1/2 hr. But at least they have some data to look at. Redridge: At least I have a backup MAF if needed

Mother, how is FVD dealing with programming your DME, did they give you hardware to download their tuning parameters... PM me if you want, thanks!

Yes, they give you a connector to hook to your port/computer and software to connect to them via laptop. You will send them your stock ECU settings and what you did to your car as far as mods, then make mods to the stock map depending on the equipment you have installed on your car and send it back into your ECU with changes. My setup is alittle harder because it is custom setup so we are gathering data with the Durametric which I send via email like the data file I posted. What I like is they are doing it alittle at a time. I sure want the first programed map in but am alittle aprehensive because I do not have and AFR hooked up. I'll let them do there magic then drive it down to a dyno for a final tune. It will be interesting to know how close they come using the durametric software and the road as my dyno. As a note when I started the car up after changing the belt it ran bad, it turns out I left off the MAF connector so I reconnected it and the car runs good again which tells me the MAF is working?

This is what I just dont understand about this whole process. Why not simply drop the car off with an FVD dealer and let them tune the car on the dyno? That is how me and my friends have done many a cars here. I dont understand how FVD is allowing all of this tweaking back and forth without their full control? It seems that things would be missed and lead to a blown motor. I am not trying to sound pissy, just never heard of so much DIY tuning before the "final" tune. I would be too scared to do what you are doing, it only takes a split second of a hard lean to blow a cylinder wall or head gasket, I know, done it 4 times with S/C'd motors. Fortunately, it was all American, cheap to fix and can make a quick turn around. The Porsche is bit painful moneywise and timewise. Just trying to understand.

What size pulley and belt are you running Mother?

JEZZ Tippy you're no fun, it's not what I will learn but is also what you will learn. Little grumpy today. 1999 I did blow the MAF so I stuck in my other used one and I am back at idle and reading 1.37 - 1.44 V fluctuating. At 6200 rpm and 4.6 V seems still to high if redline is 6800 this would put me over 5V I think and maybe causing the MAF failure? My belt is 92.5" and seems really tight, I think I only have 3/4 inch left on tensioner till maxed out. As a note the belt actually did not break but split a couple of ribs on the inside closest to the SC and shredded off. FVD now wants my stock ECU file to mod and are going to clean up the low end stumble.

Quotes source post: 4762930

Good call redridge MAF is toast. New one in and all is ok.

Quotes source post: 4764741

I don't see how it is possible to have a 92.5 inch belt if it is connected to all accessories. Depending on SC pully size, you should have a 103 - 103.7 inch belt. Too tight and you are going to fry your bearings.

Quotes source post: 4764852

The package says 93 1/8" but I measure it at 92.5', my question is what are you doing with the extra, running a cappicino machine? I think that the tensioner sets how tight the belt is and not the size of the pulley. As long as I am not reaching the tensioner limit travel during WOT I'm ok, but at present I do not know how much it travels. Our systems are different and I imagine this accounts for belt size difference.

Mother, whose SC bracket are you using, did you make your own? how many pullies are on there?...

I modified a Ford Cobra SC bracket and just using one pulley on the sc and none on the bracket, mine pulley goes directly from the SC to the Alternator. Come to think on it my injectors are Ford Racing Bosch. Should have called it Cobra Gulf V1?

Quotes source post: 4765089

Make sure you do not have to much belt vibration. Such will cause your belt to fray and split. Best to keep free lengths of belt to a minimum.

Quotes source post: 4765121

I agree, I have only 4" between SC pulley and Alternator pulley center to center. I'll keep an eye on it. What is your take on the MAF Voltage @ WOT.

Quotes source post: 4765198

I don't think you fried it due to voltage spike unless it was going bad to begin with. What size pulley are you running?

Quotes source post: 4765214

3.3" pulley and forgot to mention that the resistor wiring was fine and checked continuity through plug which was good.

Quotes source post: 4765227

The resister you are running should be fine. If you want, double the ohms of the resister.

Quotes source post: 4764741

Nah, I am not grumpy, just know what could happen with a hard lean. On the belt tension side, you could use a cable tension tool that measures force on cables and check what your belt is and what a factory 996 belt tension is. Not sure if there is enough room to get the tool in there though? Just a thought. Too bad you cant run a cog system, there is a place called ASP who make custom pulleys. With the cog set-up, you can run lower belt tensions, I loved my set-up, zero belt slippage around the S/C pulley. Probably too impractical for the 996, but keep them in mind for other pulleys you may need, they are cheap. GL, Tippy

Quotes source post: 4767917

Sorry for the misunderstanding, I meant I was grumpy. I'll keep the cog sys in mind if I find that I am slipping, my brother used it on his blown 56 corvette with success back in the day.

Quotes source post: 4768003

You won't be pushing the compressor enough to need a cog system.

Quotes source post: 4768111

True, I was talking about lower belt tension. I was running a Vortech S-trim about 2-3 thousand RPM below max impeller speed (I think like 55,000RPM), thus needing the cog system.

Well me a AAA are getting to be good friends now after another tow home during my last FVD MAP test. FVD gave me 4 base maps to test and log data to see which one works best, the first two the engine seemed to stall at idle from time to time so on the third map which was working really good especially at WOT when I broke another belt . The break was a clean one with no signs of rubbing which gives me the idea that my belt tensioner is reaching the end of it's travel at WOT or it is just a cheap belt. Last time when I installed the new belt and relaxed the belt tensioner it snaps back 1/2-3/4" from full travel. maybe not enough just not sure but think I will try 1/2" size larger if I can find. Also anyone have any recommendations on good belts? Well also took a look under my car and looks like my RMS is leaking like a 4" puddle I had a new seal put in during engine install using the newest seal and hope it was just installed improperly and will have to have that checked first before anymore runs. Regarding the belt I am using a "Gates Micro V".

I run Gates belt too with no problem. Post a picture of the installed belt and maybe something obvious with the setup will show. You may be missing an important pulley.

Mother, is your bracket similar to this?

Quotes source post: 4854035

1999 only pictures I had. You can see by the location of SC pulley that it is a straight shot to the alternator. If I am missing something why the need for extra pulleys in redridge pictures? The funny thing is that it is a clean break like it is stretched past it's limits. Also curious does anyone know about how far the belt tensioner comes back and contact belt after letting go of the belt tensioner bolt. Example almost to the of travel...in the middle .. or bearly have to push on tensioner to put belt on?

WOW, if you snapped a Gates something is definitely wrong. The stress on the belt should be relatively low due to what, 5-6 lbs of boost? Even with the tensioner too tight, it should not snap the belt. Me and my S/C friends would have one with a pry bar prying and the other tightening the tensioner bolts. I am sure we exceeded what your tensioner could put out in force. Weird. Plus we ran boost from 8-14psi. Is the belt making any funky angles that cause quick changes of direction possibly causing a whipping effect?

It's reaaly hard to tell from your picture, but if I remember correctly, you are using a very short belt which leads me to believe you are bypassing a pulley. If the belt goes directly to the water pump from the tensioner....that's your problem. You need pulley 8 to eliminate pull. It all geometry.

Quotes source post: 4854171

No, but that's one fancy pants bracket! Redridge mine is different I did not need the extra pulley, my sc is slightly lower then my alternator so I do not use any extra pulleys. Curious thought what is the belt routing through the bracket pulleys? You have one extra pulley on there for some reason. Can't seem to find pictures of back side of my bracket I'll keep looking.

Quotes source post: 4854413

Belt seems straight to alternator not sure if slapping is occuring I have no way of checking under boost, I am thinking the tensioner hits the end of it;s travel and just snaps the belt.

Quotes source post: 4854461

The tensioner has nothing to do with it as long as there is even the slightest slack in it. The belt must transverse all 9 pulleys, counting the SC's. How many do you use?

Mother, sorry to see the problems you are having with your pulley set up. It has got to be frustrating. Your engine sure looks nice and clean. When you did the interior of your's, did you have to remove the airbag control module? If so, what tool is required to remove the 2 opposing nuts on the control module? I posted a picture with my post. Good luck with the SC. Let me know if you need any interior parts. I have a few extras.

Quotes source post: 4854433

By the above picture on my routing shows the only thing that has changed is I have added a extra pulley (SC) about 6" furthor out from the alternator all other eng pulley's have stayed in the same stock positions. I am trying to make sense of the extra pulley but without a drawing of the belt routing I cannot see the relevence.

Quotes source post: 4854529

The pulleys on Redridge's picture are pulleys #3 and # 8 on the drawing.

Quotes source post: 4854487

Is the module you are talking about in the center console? If so mine was missing when I got the car and I do not have air bags, which reminds me I need to remove the idiot light. The funny thing about clean engines is they can look good under the hood but, it's what they leave behind on your driveway that gives the real story. I am missing passenger sun visor it you spot one let me know.

Quotes source post: 4854475

All 9 in drawing what if anything am I missing as I watch my dog chase it's tail...

Quotes source post: 4854588

If you are only running a 93 inch belt, I have to believe you are bypssing something. I realize your bracket is slightly different, but can it account for a 10inch shorter belt?

I must be routing my belt wrong if I use the same amount of pulleys and you are using a 103.5" belt.

Woops guess we are thinking up same lines hear and I need to put the caccpachino machine back in mine. Anyone draw a picture of there belt routing for me I seem to be inept Maybe this is the reason I am not charging my bat when I start my car?

I think you may be good Mother, but maybe you're not catching enough meat on your alternator... need to look further... BTW 1 is the very top left... left of #2

Quotes source post: 4854720

I Agree and thanks for taking the time to post pic, It seems mine is the same, but my SC alignment is different in realative terms "note modded pic". Still hard to beleive 10" of belt defference. It also looks like you are running a 3" or so inch SC pulley size. So much for hoping on the charging problem. There be enough biting on the alt for sure at idle to get a charge what should I read at battery with multimeter as far as voltage have any idea.

Mother, thanks. I need both visors. When I get mine, I'll try to snag an extra for you. I found another local salvage yard that has about a dozen 996s and Boxters ( www.mazdaporscheparts.com ).

Mother. There is no way your alternator will spin up to speeds necessary with only such a small surface of the pulley contacting the belt. Moving pulley #3 to the left will help. Or, if room, install a much larger #3 pulley? The alternator will pivot left to right. Maybe you can modify the pivot so you can move it to the extreme right which will increase the belt contact with the pulley.\ Jim

Quotes source post: 4855329

+1 The only thing I see possible is rotate the blower downward. Probably squeeze 90+ degrees of wrap doing this.

okay mother, I think I see a difference, there is a guide bracket between 1 and 9, that travel seems long and maybe vibrating modulating the throttle agressively.

just wondering if anyone has a long history of a force fed 996 and say 30,000 miles? Since it would have been less costly for Porsche to bolt a turbo on your engine rather than keep make a different block. I have been told that the 996 motor over time will not like to add pressure. I do not have a clue just looking to gain some knowledge.

Quotes source post: 4856127

I have much more than 30,000 miles on my blown 996 (3.4) and run a far greater boost than any 996 I know of running an 11.3:1 compression ratio. No problems here. No oil burning or leaks.

Quotes source post: 4856140

How much boost you running?

thanks. Any ideas as to why Porsche stays with the old blocks?

Quotes source post: 4855896

Am removing mine now, are you reffering to the guide built into the bracket that goes around the SC pulley?

Quotes source post: 4856446

yes, its a welded (on the SC bracket) strip of metal piece between 1 & 9. It also serves as a shield for the coolant hose on the left side of the belt.

Blower is off and first thing I noticed is that I could not turn the Alternator because it was hitting my SC "marked pulley with paint so I can see that it is turns now", also the alignment seems off from the alt pulley to pulley #9 power steering pump and to the alt. I'll remove the bracket tomorrow for new belt and reshim as nesessary. I try a laser light and if that does not work eye ball it I guess for alignment. Summary: The grooved pulleys alt, air pump etc have an outer ridge higher then the ribs themselves and if alignment moved the belt could have tried to jump pulley and if it was the SC pulley it jumped it's edge is sharp enought to cause belt failure. Regarding the alternator, it freewheels very easy and does not require much to turn it and if you can tell by picture I have maybe 30 percent deflection which seems ample to me, but just in case a larger pulley is needed like 1999 suggested seems the logical fix considering the SC is clocked as much as possible to get a better pulley wrap Tippy. Redridge: I may fasten the belt retainer as bolt on the SC that can be removed easily later, but do not like the idea of not seeing what is going on underneath it during testing or TS. Now if I can find a way to keep a back up belt ready to use in there without removing the SC incase of a belt mishap I know I would sleep better.

Ah yes, the misalignment must be letting the belt ride off the pulleys on to the outer retaining lips (if you will) of the pulleys, bottoming the tensioner, and then snapping the belt.

Absent of any other noticeable causes I hope so, It must be nice not having to worry about that with your turbo.

Quotes source post: 4860807

True, I love turbos a lot now. They are a pain the @$$ to setup but once sorted, they rock. Anyways, I assume you have somewhere around a 4" pulley for the S/C? My friends C6 Corvette has roughly this size, couldnt imagine any smaller due to too much boost. I could see the belt riding on the outer lip of the pulley shortening the belt like an inch or so bottoming the tensioner. In stock form, the tensioner allows just enough to get the belt over the "smooth" side of an idler, almost impossible to get the belt over the OD lips of the others.

Being that it is so difficult to change out belts that I am going to try a larger belt by 1/2" built by Goodyear "Gatorbelt" which is grooved for added grip and supposed to be vey durable. My only concern is stretch over time. My pulley size is 3.33" and sure the compressor the vette uses is different.

Quotes source post: 4862107

Sounds like a plan with the belt. Maybe if it shucks off this time, it wont break. I assume you are using the "SQ" Vortech? I thought that my friends was this trim, must not be. Then again, the Corvette uses a bigger crank pulley.

Yes. the SQ (Super Quit) vortech is the one of choice for me. Hope your right if it jumps a pulley maybe it will not break the belt.

Update: I had problems with my RMS leaking to much for me to continue tuning so the car, so she went to shop they changed the RMS using the proper tool after I explained that they used the wrong/or dated tool originally and they changed the IMS seal aslo. After airing greviences they bleed my brakes and checked Alternator and did not charge for parts so they excepted some responsibilty anyway. Well figuring I would move on with life drove my car out and at first stop light noticed a unbalanced vibration feeling on take off and accelerating I was going to turn around take it back but after talking with them just wanted to get out of there and home and maybe it would settle in. Well going up my street decided to give it some more gas .....bad move and that... was ...that ... it vibrated terrible and something sounded like it broke so pulled in my driveway leaving a stream of oil and there she sits with about a cup of oil under the eng, I had no idication of failure no idiot lights and water temp was about 170 degrees. I called the shop she said she was scared and I just said I was depressed I now spent $700 bucks on a seal that was not my fault and sounds like a blown engine to boot. I am still waiting (this happened Wensday) for a call back to see what they are going to do but still no call maybe I will try Monday besides I'm still not right in the head yet..... If it is an engine well it will be awhile before I update this thread and need to let FVD know is what's going on which I'm sure I can finish tuning when I get another engine if that is the cause. I will update again when I find out what happened.

Sounds like they botched the intermediate shaft seal replacement.

Damn Mother that sucks,i was really pulling for ya.Hope its something simple.

Quotes source post: 5027388

I was afraid you were going to say that, I had changed it along time ago during intial engine install, but the engine was running smooth when I brought it to them. She wanted to change it because it was seeping and it was very minor when I looked at it and would not notice it on the radar for quite some time if left alone but since they were down there why not.

Quotes source post: 5027459

Thanks, but to me it did not sound inexpensive and cracked a piece out of my motor bell housing. Right now I feel like I own just a big expensive boat anchor. Also need to put an oil spot under my Avatar.

Mother, I am so sorry to hear about your car. After all the work you have done, that really sucks. My heart goes out to you. If there is anything I can do to help (other than send you a boat load of cash), please let me know. I would be glad to go to the local salvage yards and check prices on engines. Autofarm in the UK rebuilds our engines...3.7 litres with the blower would be really nice. Good luck and please keep us posted.

Quotes source post: 5028429

Thanks for the time to reply from your project which I hope is going well Mfletch, But if were you I would padlock your engine right now. I paid $3000 for the engine and labor to install it so it was not devistating, but still need to do all the work over but it is a project and the radio in the car still works and I can go VAARROOOOMMMM!!!! . I was going along pretty smooth but had a gut feeling that it was just to smooth. I am still well under my target price of $20 K completed but so much for the RUF parts I wanted . Salvage yards are usually pricey but if you remember ask next time you are down there what they are asking I would appreciate that, but still need to add to my kitty, if it was cost effective a rebuild would be the way to go, but you know how that goes.

Sorry for the loss, this was the most exciting project I have read on the 996 forum. I learned some things from your project and realized how difficult it is to tune a Porsche. It is a cake walk for anything American. You could go to one website and find all the details of MAF, injector size, and fuel pump capacity in a heartbeat for boosting the American machines. Not Porsche.

Mother, sorry to hear about what has happened... I hope the GULf VI project lives on, GL

Quotes source post: 5029320

I agreeTippy and thanks, but not licked yet! I'm am not actually tuning the car like the old days just swapping maps for the mods installed in the car, but if I could have cracked the porsche ECU Gnome and knew Hex code it would be a different story. The older american cars I think are alittle harder to keep tuned.

Quotes source post: 5030067

Awesome attitude! Cant wait for future write-ups.

Quotes source post: 5029536

Thanks for the support but don't worry I'm not dead yet! Just late to the party Just waying options either go with another used eng again or rebuilt from porsche the service tech said $6500 for rebuilt from porsche with 2 year warrenty but after dropping my SC back on I would void the warrenty.

Time to update this thread. The engine I choose since I could not keep up wtih the falling dollar and pricing for the porsche rebuilt was from Strasse Auto in Newport CA and came with one year warrenty, First off Robert and thier techs seem nice and informative and have done many engines before with good feed back. Well to see that my karma is still holding up I watched them change out my injectors for my stock ones and must have went out for a qwik break and they cocked one on bank one so when my new Indy shop installed it and started her leaked fuel all over And this was after bruzing? a couple of ribs because of the zero suspenstion on my truck and those LA feeways !!! Ok enough of my whinning . I finally got her straightened out along with the passenger fan not working properly thanks for those that helped in that regard also. OK it's time to pat myself on the back for keeping the RPM's under 4000 and for the first couple of guys trying my patience in there Honda's.... and almost won . At present installing and trying my hand at painting my RUF wing, I will continue this saga after break in and SC parts back on.

Glad you're back on the saddle, you are a tough warrior! Please post more details. John

Back in the game .. after some time and changes to my intake for my SC and the bricking computer during flash I installed my SC again noticed alternator did not work so off comes the SC again, however noticed a belt problem when disassembling. The belt seem warped in one spot and just not sure of cause and this is the old belt I used before engine failure last time. Logical guessing is allowed.

belt slippage??? or you just threw it in the box mangled and packed it up.

Tough call I know but warpage is on one side of the belt, I tested the Alt and it checked Ok, but will replace the Alt/Regulator just in case. I think Im going to replace belt with slightly shorter one and mark the alt pulley and belt to see at idle if It is spinning and get voltage. You may be correct a few posts back about not getting enough grip on the alt pulley from my SC. Personally wish I had the bracket you have if you run by one let me know. The problem is I have very little area to work with on my bracket to put and idler pulley between the SC pulley and the alternator to get more grip and cannot move idler pulley #3 because it is attached to the engine thru my bracket.

Just follow up belt problem has been solved using extra pulley for more wrap and every thing was mic'd out. Now if I can get it tuned that is a different story.