First Dyno run with custom SC-Problem #'s

2000 996 w/Custom SC -This is the first Dyno tune on a Mustang dyno so feedback welcome FVD programmers are going to send new map soon and run again. Some questions though. ?. No growth in boost vs RPM stays at about 1.5-2 psi ?. Low HP and Torq dip is it related in the AFR settings range between 4400 to 6300 RPM What to check?

did u customize a VF kit? whats timing like in the middle? also 11.0 a/f seems kinda rich , explaining the dip in power maybe. PS. whats your exhaust setup?

No growth in boost suggests a leak on the high pressure side of the intake. (Or the SC drive is slipping.) But I suspect a boost leak. If so, this can account for the lower output and the rich AFR since this air has been measured and the DME will fuel accordingly but the boost allows some air to bleed away and the result is the mixture is too rich. Sincerely, Macster.

Yes, it is built from scratch however intake is the same. I did not measure today the timing using my Duramatric, however the programmers said it was not needed if I supplied it via durametric? The exhaust is just maxflo mufflers. I suffer from stalling and get some hunting then stalls and just figured it was mixture since it smells rich on startup at idle and ECU can not compensate.

thats how ur tuning it? no standalone? just letting the ECU compensate closedloop

Quotes source post: 9059116

Are you talking about a leak after the throttle body or before? They suggested a leak also, however I was not convinced the boost pressure would not rise more as the boost increased however never reaching 5-7psi target psi if a leak was present ....it just seems steady? They tap the pressure on the vacuum tube on the BOV valve for the measurement. They can do a smoke test.

Quotes source post: 9059135

Tuning takes place using FVD programmers to make me fuel maps based on the data I send them then I reload the new map and re-test.

belt slipping or vac leak would cause this. Given its a centrifical blower and you are getting 2.5lb immediately I would say boost leak. Belt slippage, unless maybe if it is really loose, would show an increase in boost followed by an early plateau as rpm's rise, and maybe a loss in PSI. What about your blow off/by pass valve could be stuck open and bleeding off boost.

Quotes source post: 9059186

The leak, if it exists, exists on the high pressure side, the side of the intake system that experiences boost pressure. Where the TB is I do not think makes any difference. Any hose the experiences high pressure, any hose fitting that holds a hose that experiences high pressure is suspect. It is not unknown for a turbo-charged Porsche to experience a boost leak and these engines are built from the ground up to run with boost, their intakes are designed from day one to contain boost up to 0.7 bar and sometimes higher if the car is driven at higher altitudes. The smoke test if it does not involve pressure may not turn up the leak if it requires considerable pressure to create. Sincerely, Macster.

did you put a resistor on your maf? With all that extra air coming in you need to lower the signal... try a 220ohm to start.

Is my check valve in right the white facing rear of eng?

Quotes source post: 9059453

I think I am using a 480 ohm now and need to check MAF voltages. I just can not remember what voltages I need to look at for it to be correct.

Quotes source post: 9059381

I was thinking of using soapy water around the joints going from the SC discharge to the throttle body. And hooking up a visual gauge to rule out a bad dyno sensor. The eng was rebuilt 5000 miles ago.

Quotes source post: 9059304

This belt is on tight and can barley get it over the belt tensioner during installation and is warm to the touch after shutdown like it is not slipping. Regarding the BOV I do need to check any suggestions...

Is the BOV adjustable? Maybe you can introduce pressure to it from a compressor with a gauge in line and test at which point it opens. What boost pressure are you supposed to have before it bleeds off? Do you know the drive pullys are right for the RPM and the boost wanted? GL getting it sorted.

Is the BOV adjustable? yes via spring what opens the valve is vacuum. As far as I know it bleeds anytime it is under vaccum or when you let of gas to create the neg vacuum. The pulley I use keeps boost a safe levels 7psi max.

I agree. Those numbers seem really low. Why did you go with this setup?

Running to rich and had to shut down.

Quotes source post: 9059116

I did have them do a smoke check and there where a couple of leaks (one at the secondary flap on distribution manifold) that have been fixed but not much change in boost until we set the psi pickup right at the manifold. My question is why do I get different boost rises at different fuel maps? Graph 1 - to rich-shut down graph 2 - babied threw the 4-5000 mark graph 4 ran ok all the way up to 7000. It's just this 4500-5500 rpm area with 5 new maps however pull 6 went all the way threw to WOT but hunted off WOT at idle till it stalled.?

Idle durametric data- Anyone know how to get AFR/Torq/HP via durametric data using spreadsheet or other means.

Just a thought; what air filter are you using? Is it sufficient to flow the CFM's needed for the Vortech? Your AFR's seems fairly steady, so I'd think the timing might be getting out of whack possibly due to the knock control making for some of the very weird graphs your car produced? Lastly, if the BOV is not staying closed, you are dumping boost - one of the biggest suspects I'd think.

Hey Tippy nice to see you're have not gone over to the dark side yet! The tuners said it looked fine and it does flow as I recall 890 cfm but pulling it off would not hurt and putting a sock over just for test. I will check the BOV, but interesting that past the problem area 5xxx RPM it can get 5.xx psi I would think it would just drop worse if BOV. Personally I do not understand how someone can tune the engine with just AFR/TQ and HP.?

Man, you have persistence! I remember you setting this car up years ago. Anyways, the BOV if adjustable, will maintain/dump at a given PSI no matter what RPM until it's flow limitations are exceeded. Wait a minute, are you sure you have the vacuum on the right side of the diaphragm? If it is wrong, you will be pushing the BOV open dumping boost. If you could take the BOV completely off and block off the tubing, then you could rule it out. Ignition timing still comes to mind with the weird crazy graph readings it produced on several different runs. And to what others have said, these belts do slip and serpentines will. At your low boost settings, it should not, but anything north of 6 PSI per se can start to cause issues on the 6-rib setups. How much percentage of the belt is making contact with the drive pulley? You need around 50% give or take.

My understanding of the BOV is that it it does not matter which way it is mounted it just uses vacuum to open the valve and is closed by spring pressure which is adjusted by changing springs. Timing is on my mind 2 also took off dyno yesterday since it wanted to try it driving around on the last fuel map and still has a small drop in the 5000 rpm area the just takes off when I got home had a oil leak which is from the AOS/crankcase breather supply line to the Throttle body or in my case back just downstream of the MAF...I just put it back on before dyno testing but seems to have popped off again. I am going to take it to have put on a lift to have a new o-ring installed and make sure it is fastened properly. At this point the tuner has not requested any Durametric readouts on timing etc.? The belt has at least 50% wrap and is tight.

You should be using a pop off valve for a supercharger. Not a dv. When using a dv on a MAF metered car the vent side needs to be routed back into the intake after the MAF sensor. I take it this isn't your setup as I seemed to have over looked your added description on the picture of the outlet of that dv being hooked up to the inlet.

5k rpm is around the area original variocam returns cam timing back to normal from the advanced state. I can feel it on my car if I'm really concentrating. Wondering if you are just feeling this change "more" dramatically because of the FI. What does your cam deviation read out for both banks from durametric? And can you monitor the actual angles value through the rpm range to validate variocam is working right?

Quotes source post: 9086077

That is the way it is just the hose is not connected in picture it takes charged air back to downside of the MAF before it is compressed. My understanding of Pop is it vents to the atmosphere.

Quotes source post: 9086078

I just tried to run data w/durametric and engine stalled few miles down the road so could not get wifi to verify the data cable-why could they not log ecu info in the cable without verifying via internet!!!!!!!!!!!!!!!!!!!!! Opps sorry for the rant but my dog is no where to be found. I will try data run tomorrow again. I understand the kick you feel however some of the dyno runs of vf setups show a smooth torq/hp and afr despite the variocam which not familiar with what is supposed to do however mine simply wants to backfire like it's to rich then shoots straight up to WOT and hunts and dies after idling to much. I am hoping to get some SC durametric data for comparison. I went to another dyno shop today to have a leak fixed and spoke with there programmer said that the AFR looked pretty good but of course ended up in a guessing game after we sat and watched it hunt and dye. We did agree that these newer cars cannot be tuned like they did back in the old days with more and more sensors.

Sorry I can't be more help ;-) It's just been too long since I supercharged and tuned anything. My last was when I put a Judson blower on my '59 VW bug in the late '60s. It had a single throat Solex carb with a single mixture screw to turn and I could loosen the clamp on the '009 Bosch distributor to tweek the timing. It was fun, ran great and I'll bet it boosted that 36HP motor to about 50!

Sorry to hear about the dog. Durametric can be a little tricky.

Has anyone seen a excel spreadsheet xls that can draw graphs using Durametric software data for tq/hp/afr, Brockway uses there or odb2 port and believe even NB O2 sensors and figure out what your afr is etc. The only one I have found that maybe can do it by importing excel data but have not got it to work.

Excel has graphing integrated, but it is somewhat a manual process. I looked into calculating the AFR but if I remember right to do it in something like the spreadsheet you posted on renntech it required more software and wideband sensors. I would be curious if you find the solution!

I think you are right I have tried this excel importing xls file maybe you have better luck it's the zip file. http://www.renntech.org/forums/topic...raphing-tools/ I do think I need a wide-band sensor but I was under the impression that Brockway odb11 setup plugs in and can use our narrow-band sensors to get the afr maybe wrong here but you can tell about where you are with voltage of the o2's. When using real time values with the durametric you can see the graph of parameters that you are tracking via graph in the program but when exporting all I end up is the data gets to be frustrating.

Wow, that is a pretty intense spreadsheet and it looks like some parts might be missing to make it work, I get an error about missing activeX controls. Anyhow, maybe this will help. I'm sure you know this already but if you are driving around or even parked idle, you should have your laptop connected to a power inverter otherwise Durametric will not log data as frequently (which is also a parameter you can change within software). Once you've logged your data, it should be possible to work out the formulas to calculate and graph the AFR. Here's a thread from the turbo forum about what to log and how to calculate AFR from Durametric data. http://www.6speedonline.com/forums/9...ml#post3379343 " Rich versus lean, why lean makes more power but is more dangeros A stoichiometric AFR has the correct amount of air and fuel to produce a chemically complete combustion event. For gasoline engines, the ratio is 14.7:1, which means 14.7 parts of air to one part of fuel. This ratio is dependent on fuel type-- for alcohol it is 6.4:1 and 14.5:1 for diesel. Durametric reports lambda - a percentage of AFR based on the stoichiometric ratio. To report the proper AFR from Durametric, multiply the pre catalytic actual lambda by 14.7. For example, a lambda of 0.78 gives a AFR of 11.47:1 (0.78 * 14.7 = 11.47.)"

With the spreadsheet open try on menu bar excel tools-options-under security button choose macro security and pick lowest setting to allow the active x buttons to work then you can work with importing your durametric data etc. Thanks for the conversion on AFR. PS I do use a separate power converter connected to the cigarette lighter. Most of the info I read is that they use wideband for AFR and not sure of the correlation as of yet to narrowband.

I am thinking out of the box becasue I know little about doing any super charger work. so this may sound silly. But to me sounds very plausable Couldnt you tap in a pressure fitting from a shop compressor and put your pressure to it and see if it holds? I was thinking this may not work becasue an exhaust valve may be open. But no exhaust and intake valve would be open at the same time... So it should hold pressure. And the motor wouldnt be running so you could hear what was going on.

I had a smoke test check and repaired couple of leaks however this test does what you are speaking of and the tech told me it was ok..I think he used around 10psi.

I can't believe you're not using a real wideband. This is such a cheap fail safe sensor that is needed, IMO, when boosting any car. I always have to know what my AFR is at all times when I am running that kind of setup bc something can go wrong at anytime so that way you will know when to shut it down before it is to late. I mean they're only 225 for a standalone kit that can be plugged into most every tuning software. I'm surprised the tuner even wanted to tune your car on a narrow band.

Quotes source post: 9098307

I agree with you here is my PayPal account so you can pony up: [email removed]

haha

In all seriousness, you can't get an accurate AFR from a narrowband sensor when you're outside of it's range. If you're not going to run a wideband during normal operation you should be running it on the dyno (which I think you are). Things won't change all that much after you get things tuned (unless something fails), but at this point you don't even have a base tune setup if I understand your posts so far. I really wouldn't be running this car until I got things sorted out in a safe environment (dyno or no-load street driving).

Curious. Why didn't you go with vf file from GIAC for 1200 as where fvd is 900 and you are having these issues? Not saying it is tuning related to your issue but it would rule that out to have a solid tune that doesn't need to be sent back and forth. Why is there a need for a ohm resistor in the maf when the car is supposed to be 'tuned'? What injector brand/size are you using? What size is your pulley? Are you running an upgraded fuel pump? Just wondering on those questions as I'm looking into picking a kit up as well.

A base map is basic "safe" settings in each tuning window and is usually only tuned up to a certain rpm so you can drive your vehicle to a tuner. It's main point is to get you started. Not really to run flawless.

Quotes source post: 9099864

Loads of info on my build: https://rennlist.com/forums/996-foru...-tuning-6.html The VF program is not customizable and not sure it would work on my car and no guarantee. Short Story at the time FVD said they could tune and where also had a tuner in Florida (now obsolete) and if I purchased there durametric software for on the road dyno logging parameters and there tuner would tune, however what I ended up with is a basic flash and no tuning that helped they just played with the AFR and with little to no correspondence - I would not use them again because they just have not done it before I did get a flash that works with my 48 LBS injectors. Stock fuel pump works fine depending on what HP you are trying to reach. If you are picking up a kit then you will have everything you need but try to find someone local to install or should work fine if engine is in good working order? The resistor is size depends on MAF voltage as close to 1V because of the extra air at idle and around 18-20 kg/hr mass air flow. The puleey etc in mentioned in above thread.

I spoke with vf and they said they have had a 997s at 475 with the same kit but on race gas. I know it has a few more liters than us but... They use 42lb bosch green injectors also. I asked about a 4-450 hp mark and they replied the oem pump can't handle that flow. Is there not a GIAC dealer near you with a dyno? I know they have made plenty of custom files for Audi guys with custom setups. I just find it weird you have to 'fool' the maf for a tune. Sorry not going to read through 12 pages to see what size pulley you used but I'm assuming 3.25" since that is what the vf kit uses for 6psi. I will be adding to the kit to run atleast 400 whp. I have all winter to gather my parts I will be using. There are plenty of tuners and dyno tuners in my area with ones I am friends with as well so not worried as much. If I were you I would mimick as much as possible vf's kit to get it running right then tweak it to your liking since you are having major issues.

Quotes source post: 9100214

This isn't far from stock specs IIRC, in fact might be just about spot on (at idle mind you). I'm almost wondering if the resistor is causing the problems, or there is a problem with intake. If I remember right, there was a highly technical discussion about AFR, MAF resistor, and intake size on renntech.org which included 1999porshce911's advice. I'll try to dig this up in case you haven't read it. It might have been this one??? http://www.renntech.org/forums/topic...el-air-mixture You've read it right? LOL on the donations, you're the one that has shelled out all those bones for a custom FI setup!

Quotes source post: 9100262

Yes it is a 3.25 but if building your own the knowledge in that thread has got me hear The boxed injectors said 42lbs but had them flowed tested within 2 percent of each other and folowed 48lbs. My build is very close but could be just far off enough to have a VF software be useless. I will see about the GIAC and have not check the phoenix area. some pics of my build http://www.webbspot.com/porsche/ Forgot to mention the intake has changed on website and has not been updated in years sorry.

Quotes source post: 9100340

I agree with it not being far off on the kg/hr it seems when go to WOT them slow some push in clutch it hunts and dies but driven normally seems to idle so beats me tune or May when rain stops I will change out the resistors.

Update: Well back to drawing board the SC high speed bearing is KA-PUT and the timing is way off.