2001 C2 engine going - 3.2 swap

Hello Rennlisters, I have good and bad news. I have a 2001 C2 996 with 153k mi.. ..well it wasn't the IMS that failed. I have it as my daily driver and it is now diagnosed with a rod bearing knock. I'm not sure how much longer I will be able to drive it. I have a low budget and plan on doing a proper rebuild but in the meantime I either have to get a beater to drive during the rebuild, or I was considering putting a boxster 3.2 S engine as they are cheaper than the 3.4 at least until the rebuild on the other engine is complete. Here are my assumptions 1. 3.2S and 3.4 engines are the same block. 2. 3.2S and 3.4 engines are interchangable without fabrication. i.e bolt on swap. 3. no DME reprogram would be necessary if I used a 00-02 3.2S engine. Am I correct? Are there any gotchas in doing this other than a bit of reduced HP?

It might be cheaper to buy a 2.7 boxster, drive that until your car is done and sell the boxster.

Maybe cheaper again if you ship your present one as core to the place that sells the Boxster 32 S. That's if you are keeping your car. Macster may advice you on the best move I think.

White Out, Thanks for the reply. You know, I was lurking your forum posts last night on that other site. Thanks for the other suggestion to get a Boxter or another car during the rebuild. I really like driving my 996 and it is in great shape despite having 153k mi on the original engine. I'm looking at this - http://www.ebay.com/itm/2000-Porsche...ht_1172wt_1091 If I can install this low cost and just swap my 3.4 brackets/harness/accessories without expensive modifications or DME changes. Once my original engine is then properly rebuilt I can resell or keep the 3.2 block. Is this possible or is my line of thought incorrect?

Are you doing this all yourself?

my 2 cents: pay for a rental car while doing the rebuild

Yes, I would be doing the swap myself. I've done a lot of work on my 996 and find it enjoyable to work on. 50% of the fun in owning a Porsche in my opinion is getting to work on such a great car yourself. I've already had most of the intake manifold off to change the AOS. Dropping one engine and switching all the intake/fuel rails/accessories/ harness/ and sensors should be relatively straightforward. I'm looking if there are those gotchas like... "hey the block on the 3.2 is the same but some of the holes aren't drilled and tapped for use in a 996 3.2" I don't think there are any.. but that is why I am asking now instead of waiting until I am 3k into an engine I can't utilize.

Search for 3.4L engine upgrades on Boxster threads. You would be doing it in reverse. I thought you had to swap out the DME in the Boxster during the upgrade but a few guys who have done it would know better..

Yes, my understanding on the DME swap for a boxster is only required if you stay out of your year group. Since I have a 2001 C2, with eGas I should be able to swap with a 2000-01 boxster 3.2 with motoronic 7.8 (non CANBUS) and electronic throttle without any changes. If I were to go with a newer boxster, carrera 3.6, or 997 engine I would need to update the DME to the CANBUS (and all the required components) in order to be able to operate the VarioCam+ feature of the newer engines. The long block I am looking at is a 2000 Boxster 3.2 with 64k mi. Earlier engines may work but would have to use the correct throttle body.. electric vs cable driven, but the computer may use the electronic throttle position to manage the engine. I'm not completely sure.

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Amille any 2000-2002 3.2 will do what you want with the most noticable drawback being the loss of 33 ft/lbs of torque. That will be quite annoying & may cause clutch wear to increase. The case & head raw castings are functionaly identical but the boxster heads will need to be drilled & tapped to bolt on the 996 intake manifold & the exhaust heat shields. There may be more steps like this required but I believe they will be minor, however I have not done this so I can't be certain. DME wise you will not need to change anything.

How will a weaker engine increase clutch wear? I say buy a cheap VW TDI and drive it until the rebuild id done. This way you'll have somethig to drive that costs next to nothing and saves you money to pay for the rebuild.

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Slipping the clutch for initial takeoff

ECU changes are going to be your biggest issue. I totally understand your want to drive the 996 constantly. But financially, it might be a better option for you to drive something else for a few weeks/months. Try E30/E36, boxster, something to haul engines, etc. Thanks for following the blog!

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There is no noticable difference between the engines at take off RPMs.

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Losing 200cc makes a very noticable difference especially at low rpm.

Just how much tq do you really need to get a ~3k lb car off the line?

I appreciate the responses. As far as the .2 displacement, I understand the car will be a little bit slower. I don't think I will notice much difference between a fresher 3.2 vs my old and tired 3.4 with 153k mi. Engines, like people, lose performance as they get older. I'm sure if I took the car on a dyno today it would not be close to stock. This car is a daily driver. I enjoy it as such. Plus it gives me a second block to possibly send to LN for the 3.6 upgrade later down the road. I compared curb weights between the 01 boxster S and 01 911 C2. The difference in weight is about 135 lbs. I don't think I will have any noticable difference in clutch wear.

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you have absolutely no idea what you're talking about

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Clutch wear is 100% dependent on the pattern of use, vehicle power, and vehicle weight. If you know how to properly drive a manual transmission, your clutch will last you a lifetime. To even suggest that going from 296hp to 250hp would cause premature clutch wear is ridiculous. If anything, his clutch will last longer as it has to handle LESS power coming from the engine. Based on your "theory" every Honda or Toyota with manual transmission that has 1/2 of the HP and 1/2 of the displacement of boxster should go through clutches every 5k miles? LOL.

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How much cheaper is the 3.2 vs. the 3.4 (or even a 3.6) engine? How much work is it to adapt the 3.2l engine to the car or vice versa compared to a 3.4l or even a 3.6l engine? I do not know the answers to these questions but you need to know the answers. If the 3.2l engine is a drop in and go swap I guess it makes some sense to use the 3.2l engine but you have to be sure it is a drop in swap. I can't helkp you with this. You'll have to find someone who has done this and has the answers or you'll have to break new ground. Hard to believe you would be the first to go this route, but you might be. Most (all?) others go the like for for like (3.4l for a 3.4l) or go for the gold and install a 3.6l in place of the 3.4l engine. Do your research. You can spend a lot of time (and money) putting a square peg in a round hole (engine swap-wise) and easily burn more money than you would have had you just opted for a 3.4l engine in the first place. And end up with something less than the sum of its parts. I can't speak with any real experience to the HP diffs. Just thinking out loud, it is possible there can be driveability issues. While 200cc's diff and the lower torque output of the 3.2l vs. the 3.4l may not seem like much, your car's transmission is likely geared to take advantage of the higher torque output of the 3.4l engine. (If you find the 6-speed for the 3.2l engine is geared the same as the 6-speed for the 3.4l car then never mind.) I recall how the 5-speed in the 2.5l Boxster had some different gears ratios compared to the gear ratios in the 5-speed in the 2.7l Boxster. The 2.5l gear box ratios were IIRC a bit closer to make up for the lower torque output of the 2.5l engine and the 2.7l gear box ratios were a bit further apart to take advantage of the higher torque output of 2.7l engine. It is rumored but backed by some number of posts that the clutch life in the 2.5l Boxster was affected by the engine's lack of torque. More clutch slippage was needed to get the car moving. But the short time --- I hope it is a short time -- that you have the 3.2l engine the car the clutch should not suffer any (if at all) beyond what it would have experienced with the 3.4l engine. Also, when you drop the 3.2l and install the rebuilt 3.4l you can certainly examine the clutch and make the call. But the 3.2l engine gets you back on the road in your 911 -- provided, always provided the 3.2l "drops" in with an acceptable amount of work -- while the original engine is out getting a rebuild. Provided the car is still driveable with the 3.2l engine (and I suspect it will be) I think you'll be ok. But no guarantees. Hopefully your research will turn up no real driveability issues or issues related to the installation and that's that.

[QUOTE=Byprodriver;10846845]Amille any 2000-2002 3.2 will do what you want with the most noticable drawback being the loss of 33 ft/lbs of torque. That will be quite annoying & may cause clutch wear to increase. Guys, often times ALL the words are important!

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I guess my 3 year stint (2000-2003) as the official test driver for PCNA western region press fleet vehicles didn't help either.

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[QUOTE=Byprodriver;10852220] Why should it?

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What does that mean?

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That means he may be a good driver but not so sure on the mechanics side.

I thought press fleet cars are for the press. Maybe they need valet service in between appointments?

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Means that he stayed at the Holiday Inn Express!

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don't care. You are not displaying sound reasoning. The amount of torque required to get a car off the line is so small (especially on flat ground) that is almost not worth talking about. Considering you can get a car moving easily without any throttle whatsoever at idle, the tiny bit of throttle/torque required to get the car moving with only the slightest clutch slip is well, well, well below what either a 3.4 or 3.2 produce at take off rpm. And if it were such a concern, which it isn't, an extra 100-200rpm would easily solve the problem anyway.

Takes a bit more if you leave the handbrake on though.

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Getting the car moving without any throttle is I think an artifact of the e-Gas system and the desire to maintain a specific idle speed even with some load present. In the 3.4l 996's with the older idle air control valve system and manual throttle control I'm not so sure this getting the car moving with no throttle is realistic. Now I admit I have never driven an older 996 and do not know how the car would behave moving off with no throttle just extra smooth/slow clutch engagement. It could it would be just fine.

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It works downslope and on the level, but not on much of an incline. At some point I have to clutch out to prevent stalling whereupon gravity takes over.

Thanks to all who contributed to helping me make my decision. I'm price comparing engines right now but I think I will end up going with the used 3.2 if I can find one at a good price. I guess the only way to tell if this will work and do some mythbusting is to actually try it. I spent a considerable amount of time reading the boxster forum on the 3.4 to 3.2 swap. One of the big problems is with their intake setup but I plan on using the 996 manifold so I think the swap from boxster to carrera might be easier than the other way around.

Just curious and why not go the other way and get a used 3.6 bottom end with the 3.4 top? I would rather do that than mess around using a 3.2 for awhile if you're gonna go through all that hassle. Just my $.02

I think what you are trying to say is why not use a 3.6 bearing carrier and crank assembly in the 3.4 engine case?. The stroke on the 3.6 bearing carrier crank and rods is longer and would cause the pistons to hit the valves and bend them. The bearing carrier in the boxster 3.2 and carrera 3.4 are the same, they also share the same heads. The only difference is the engine case, which is the same casting, but the 3.2 has smaller diameter pistons. I think 92mm vs 94mm but im not 100% sure on those sizes. The short answer to why not is cost... i plan on just dropping in a used 3.2 long block engine without tearing it apart for a rebuild.. I dont have many of the special tools required for rebuild.. and its about 2K to replace everything that would really need replaced to do a proper rebuild. Head gaskets, piston rings, carrier and rod bearings, seals, gaskets, chains, chain follower, machine work.. and while your at it why not put some of LN's billet stuff in there, forged rods, ARP bolts, $$$$$$$$$$$$

I think what he is saying is to use a 3.6 shortblock and bolt on the 3.4 heads and intake.

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Bingo Take this opportunity to "upgrade" instead of just repair...

Has this been done? My understanding is that 3.4 heads won't work on a 3.6 case. (unless you have a 3.6 LN engineering Nikisil case). Please correct me if I'm wrong. It will make me happy.

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There's at least a couple that has done this including one member here on this forum. IIRC, he didn't even have to reprogram his ecu. I hate to say it but do a search and you will be able to find him and maybe message him on certain details.

Amille......there is no case on these engines, its actually a more or less a standard engine block. The cylinders and the bottom end are one. Two halves for each bank but the cylinders are non removable.

This is looking like a "downgrade" rather than an upgrade. Not to rain on your parade, but anytime you change the standard configuration on a Porsche you are going to incur significant costs in $$$ or time. A change in engine type is not going to solve your resource issues. Don't chase the rabbit down the hole...there are lots of really knowledgeable people here who are saying this is a false economy. Cheers, TomF

Well I am engaged at warp speed down the rabbit hole. I'm about halfway complete with this swap. We will see how it goes. At no point did I say I was desiring an upgrade or wanted to increase performance of the car in any way. I am curious to see if I will even notice the difference.

We just had this conversation on the 986 forum http://986forum.com/forums/performan...boxster-s.html If you swap your intake and exhaust manifolds onto the 3.2, you'll only be down about 15-20 hp, not 46. Porsche killed the 3.2s performance by restricting it's breathing.

Thanks for the link. I agree with the posts that much of the difference between 3.2 and 3.4 engine's performance variation is intake/exhaust related. If anyone is curious within a week we will have hopefully an example to dyno. I must say the engines are extremely similar on the outside. I did have to drill and tap holes for the 996 exhaust hangars and the intake manifold. I purchased a long block so I am still in the process of swapping everything over. When finished I will have a stock 01 996 everything with a 00 boxster S 3.2 engine. I'm thinking some simple mods such as high flow cats, IPD intake plenum, and possible 3.8 exhaust manifolds might net the difference 0.2L There are many people that in the Chevy LS world substitute a 5.3 engine vs the LS1 5.7. A set of decked heads, Z06 cam will give very similar performance in a vortech 5.3 with a 5.7 LS1. My car is a daily driver and I love driving it every day. My bet is that my tired 153k mi 3.4 was probably out the 20hp anyways from being old.

Ecellent! Document everything and post it for future reference.

here is the 3.2 posing as a 3.4 Install is finished with 150mi on the 3.2. Runs and drives great. The swap was not overly difficult. Everything from the 996 engine exterior was used on the 3.2 longblock. Performance feel is crisp and very drivable. It is hard for me to make an apples to apples comparison. The newly installed 3.2 has a brand new clutch and excellent throttle response.

Amille, Nice work good to see it was a success. What was your approximate cost and time for the complete changeover?

Street Rod. Total time was about three weekends worth of work plus a few nights of project time after work. The hardest thing about the project is that each 3.2 head requires 9 holes to be drilled and tapped. The intake runner on the 996 engine is different and the holes for the 996 exhaust hanger bracket are not drilled and tapped. An M6 and M8 thread tap and recommended drill bit was used to do this work. If I had to do it again I would pay a machinist to do this. Cost is where this swap takes the cake. Used 62k 3.2 longblock eBay - $2,500 Shipping - $200 Clutch kit- $360 Gaskets - $100 Fluids = $100 Bits and taps for drilling holes - $25 Many of the items on the old engine were already new. My rod bearing went.. so in troubleshooting I replaced a bunch of stuff hoping that it was not internal engine related. AOS, water pump, coil packs, spark plugs, oil tube, vacuum lines, and coolant tubes were all less than a year old on the other motor so they were direct swapped over. I would argue this is by far the cheapest way to get a 996 back on the road. I also have my old core. Next project will to see how rebuildable it is.

This picture shows the four intake runner bolt hole locations that have to be tapped on the boxster S head. Also the three larger exhaust hangar bolts 8mm X 1.25. There are two additional holes on the exhaust side of the head that need drilled/tapped. (not shown in picture) Be careful if you do this yourself. This is something you measure, then double measure before drilling. Also pay attention to the depth of the holes needed. This takes a long time to get right mostly about being careful. If I did this again I would pay a machinist to drill and tap these holes.

The studs on the 996 oil pump housing have to be removed to use on the boxster motor. Use the nuts that hold on the rear engine mounting support. Jam the nuts together(seriously) and you will be able to remove the studs

While the engine was out, I took the opportunity to remove the foamy stuff in the engine bay as it was heavily cracked and flaking off. This stuff lines the area above the plastic intake spider. I replaced it with duramat type sound deadener/heat shield. The stuff is peel and stick, very easy to put on.

Is the new sound deadenning tar based? Also, those 4 intake polt holes are already drilled just needs to be tapped?

Great DIY and interesting approach to your problem but this is why you dont depend on a 996 as a DD. I think it would have been better to just rebuild the 3.4 or find a 3.6 but still you made an interesting swap. Hopefully you will be able to recoup some of your 3.2 money buy selling it when your ready. Good job!

I do not think the sound deadening is tar based. There are many different brands of the same stuff. I got mine from the local speed shop for about $40. Here is an example. http://www.eastwood.com/dynamat-extreme-bulk-pack.html As for the holes they need to be drilled AND tapped. The bosses are there for all of the holes but different ones are drilled on the 996 vs 986 head. I have to say it was a fun experience.. I don't think I'm hurting performance wise. This thing pulls and sounds amazing from 4-7k RPM. If someone lives in the Washington DC area they might be interested in doing a stock 996 to 3.2 swap 996 review or driving test. I'm really interested to get an objective opinion on the swap.

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I cound't DISAGREE more. This is an excellent option, 20hp to save $5000 is a very good trade off. Drilling and tapping a few holes is penuts for a DIY-er. If I wasn't able to fix my 3.4, this would have been the next best option. Heck, even that it "only" cost me $2000 in parts and a lot of my time, the 3.2 was even cheaper. WELL DONE!!

How is he saving a dime, much less $5000 if hes going to repair the 3.4? Hes merely DELAYING that expense while he spends less right now. If hes not able to sell the 3.2L when his 3.4L is ready how exactly does that save money? Im not dissing his DIY ability, I just dont get the reason. To me it just made more sense to park the car with no engine while you repair and or upgrade the 3.4L. A good start would be:

There are differences on the philosophy of use of the car between owners. I get it that some folks want a high performance show car. They want to get as close to performance to a GT3 as possible with a LN engineered Jake Raby super machine. Don't get me wrong, im as envious as anyone else of who has one. They are great machines and those folks at Flat6 or LN do great work. The bottom line is I just can't afford that. Maybe I shouldn't even own a Porsche at all, but I do.. I own a 928 as well and I love the spirit, and I love getting in my used 996 and driving it to work EVERY day. I personally believe these cars are meant to be driven. They look great on the road and even in DC they are a rarity. I'm not going to repair the 3.4 anytime soon.. it will be a garage project. I have some mechanical ability with cars, but to rebuild a flat 6 motor takes some know how. How many rebuilders out there that do this every day have a bad rap? It's easy to make a mistake. It is not as simple as a 1.5k$ rebuild kit.. thats just the beginning.. you have to inspect the cylinders... I'm pretty sure i snapped a rod when the engine gave out. What about if the crank is scored or the bearing carrier is damaged. There could be 4 or 5 other issues I find that add up to $$$ How many times have we read on this forum. 'I want to increase performance to XX' and the response is ' you should buy a 997, GT3, or turbo' How many have gone down mod avenue to only end up selling the car a few months after the nightmare is over. How many swap and rebuild services are for sale on ebay. Any happy takers out there. For $3,000 I could drive my 996 every day, blow a 3.2 every two years and my total investment is $125 a month. Its an option.. and for the 20hp loss.. maybe not worth it to the individual. I seriously invite anyone to come drive it and see if they don't smile when the thing bounces off 7000 RPM.. If some of us are willing to work together.. we could baseline the performance of this setup and find a way to get back the lost 20hp. I'm thinking a combination of possible LN low temp thermostat, an underdrive pulley, and possibly 3.8 headers might show some gains. The answer to so many long time 996 owners with IMS or failed engines doesn't always have to = $$$

Great work Amille. Please record the acceleration videos and post them on Youtube. This way we can see how the car performs with the 3.2 motor.

Does the video go like this? hehe

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+1 2003 Carrera 4S Speed Yellow / 1955 356 Continental 1500 Rust Red

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While I totally agree with your reasoning I just wanted to point out that I did have a good experience with one of the ebay rebuilders.

Stjoh, You're right I shouldn't make blanket statements. There are reputable rebuilders out there. There are a lot of horror stories on this forum as well. If you've had a good experience you should write a thread detailing your experience so that other folks can make the right decision.

KK.....how he sawed $5K is simple, leave the 3.2 in there and forget about fixing the 3.4. Heck if the 3.4 is good enough of a shape to be a core, it can be sold for almost as much as this replacement 3.2.

Because I based my commnet on his above statement. If hes changed his mind and is now happy with the 3.2 then it does make sense. Either way I respect the work done by him and what youve done with your project.

As for now the 3.2 is staying in. I really thought that the performance might be underwhelming... but this is not the case. I love how it drives with the 3.2. I'm hoping this motor will last me 2-3 years.. and by then slowly I should have the other engine refreshed. If the 3.4 is too badly damaged, I may sell the case halves and heads to recoup my investment on the 3.2. I plan on keeping the car so I will eventually probably rebuild the 3.4 and keep it as a spare. Keep in mind the similaraties between the 3.2 and 3.4. Same camshafts, same crank, bearing carrier, rods, both sets of case halves can be relined at LN to 3.6. There is a member that liked the idea that the 3.2 had thicker cylinder walls and used the 3.6 bearing carrier and rods to make a 3.4. (smaller bore with longer stroke) If you plan on keeping the car for a long time having two engines might not be a terrible idea. Of course the more mods and money I put in it eats away at the savings I have now. I just wanted to show what options are available.

Way to think outside of the box. Congrats! Much better than just blindly throw parts at a car.

What a great solution IF you suffer an engine failure. I think you came up with an affordable alternative and you did it in your garage, outstanding.

I wanted to bring up one interessting thing I noticed between the 3.2 and 3.4. The boxster S AOS has no coolant lines running to it. The 996 AOS has a coolant line that runs from the flange under the alternator, over the intake runners, then another line that I forget where it runs (maybe to the oil cooler). Does anyone know the purpose of running coolant through the AOS? I was thinking of just running a coolant line from the alternator flange to wherever it goes (oil cooler i think) and using the boxster S AOS. My 996 AOS is new because I snapped off one of those coolant lines, so it seems like a point of failure. This would also reduce the amount of lines above the engine in that hard-to-get-to area. Another mod to clean up the engine would be the secondary air injection block-offs. I'm not sure how the vacuum lines would get routed if this were all eliminated. I'm registered in FL with no emissions requirement. Is there any change in performance by eliminating this system? CEL?

I suspect there is a layer of insulation since the boxster engine placement is in between the passenger compartment and trunk. Running coolant depends on where you live and how cold it gets. Another option ala BMW is to insulate the lines with foam if they aren't too close to any really hot parts of the motor.

Why does the AOS have coolant routed to it? Impossible to say for sure but my WAG is to keep the AOS warm to avoid water vapor in the crankcase fumes from condensing out as the fumes pass through the AOS. We know water can condense out of the crankcase fumes in cooler places. Enough owners have posted questions (and pics) of their engine's oil filler tube and cap and the gunk that collects from water condensing along with entrapped oil vapor at that cool location. In colder temperature the water could freeze and collect as ice and possibly block air flow through the AOS. There is also the intake to think about. Even if the water doesn't condense in the AOS it can condense when it reaches the even cooler intake where it then enters the combustion chamber. Or again in colder temperature could freeze/build up ice in the intake and if so I would not like a chunk of ice breaking loose from the intake and ending up in a cylinder.

If you're gonna do a 3.2 swap, you might as well go old school and find a 3.2 out of an '84ish Carrera. Do it. You know you want to.

Mcaster, If that theory were the case, why would the Boxter S AOS not have the coolant lines to it? I'm wondering if the increased heat from the coolant helps do a better job of separating oil from the crankcase gasses. Do you know if the super AOS (I think it costs about $500) that they have as an upgrade has coolant to it? I'm willing to bet the same guy that designed the IMS designed the AOS. I've seen the thread you refer to with the oil filler neck. My opinion would be to clean it out with a rag and drive the car every day. I have a Ford Expedition as well and it has an extended fill neck. The same residue is present when you flip the cap over if the truck hasn't been driven in a while. If you drive the car often less moisture builds up in the crankcase and you will have less gunk in the tube.

The most popular theory I've heard about the Boxster vs. 911 AOS is that the Boxster's AOS is placed in a hotter area of the engine compartment than on the 911, so it doesn't need the coolant hose running through to keep it warm enough to burn off the water vapor.

heres some food for discussion http://www.jegs.com/p/JEGS-Performan...63433/10002/-1 JEGS Air Oil Separator is designed for vehicles with positive crankcase ventilation systems. This air oil separator prevents oil blow-by from being displaced into the intake tract on engines where crankcase pressure is high, such as high-RPM applications. When installing, always route separator away from heat sources. Made in USA.

http://experformance.net/i-1831133.aspx This one is different and has coolant flow. Heated By Coolant The base plate of the the AOS is heated by coolant drawn from the engine. By keeping the AOS the same temperature as the engine and blow-by gases, water condensation is decreased allowing oil and water vapor to separate and pass through the can. This vital feature eliminates nearly all the sludge that can build up in the AOS body, which drastically reduce how often you must clean it. So it looks like the AOS is attempting to keep at the same temperature as the engine in order to minimize sludge buildup. I haven't read about any boxster owners who had failed AOS due to sludge buildup. This of course could be due to the engine compartment being hotter on a boxster, however I'd venture to say there is not a whole lot of difference. The 996 AOS is pretty close to the engine. If the 996 AOS fails you can bet its getting replaced with a boxster AOS. I'll reroute the coolant hoses. If you really wanted to go crazy you could cut apart an old AOS and make a flange, use it to route a custom catch can system that is in an area that is easy to get to.

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I vote this route if you're the kind of guy that actually checks his own oil and tire pressures without the need of a dummy computer monitoring them for you. Catch can would be the most reliable and straight forward system but unfortunately, not everyone is hardcore enough to check and drain the catch can on a regular basis. And heaven forbid a Porsche owner having to get their hands dirty for something like this as they still struggle to get their hands dirty to even change a tire... Factory Porsche Tire Changing Gloves. Factory Part # 99991400140.

Mcaster has his own theories on the AOS coolant lines that are dangerously convincing if you don't know any better. Part of it is accurate and that's what makes it so bad. We have discussed this in another thread about a week ago but looks like his theory remained unchanged. My theory will not be a 500 word post. It's there for extreme cold conditions where the trips are pretty short.

I don't have a dyno or access to one but am trying to assess the performance of the car. Can anyone with a 3.4 996 tell me what speed they hit in 2nd gear at 7000 rpm? (not going downhill or uphill)

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Might be easier if you download one of the many Smartphone app HP calculators. I think Bosch had a free one at some point. I know most peeps these days have smartphones so you might be able to compare data slightly more accurately.

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http://www.californiamotorsports.net...ck%20gears.pdf

Ahh, search is my friend... from another thread... For a six speed 1st=~42 MPH 2nd=~70 MPH 3rd=~102 MPH 4th=~127 MPH 5th=~154 MPH 6th=~190 MPH These are also with stock size tires. In the TIP's 1st=~45 MPH 2nd=~75 MPH 3rd=~119 MPH 4th=~169 MPH 5th=~202 MPH Again with stock tires. Note - these were the best approximations I could read from the graphs I have. I'm hitting 71mph at 7000 RPM in 2nd gear. So I think my performance is pretty close to stock.

What does max speed in each gear have to do with performance?

I have retrofitted my 01 996 c2 with a 00 Boxster S 3.2l engine. I am trying to make a comparison of performance difference between the 3.2 and 3.4 engines. the only difference between my car and a stock 996 is 200cc's of displacement. With the same gear ratios (because a stock 996 and my retrofit use the same transmission), I would want to see how the top speed at top rpm compare between the two engines. If they are close to being the same I can assume that the performance between the engines are the same. (or similar for the technical ones out there) Ultimately I would want to make this comparison over every speed and every rpm, but I don't have a dyno. Check this out if you want to blow your mind on a Monday night. http://www.f1technical.net/forum/viewtopic.php?t=2218

Speed will be the same if you have the same transmission, engine has no effect on it. So, if your 3.2 can rev as high as 3.4 and you kept the original transmission, your speed will be the same at any given RPM with both engines. I don't see what "performance" difference you want to see with speed and RPM. In any given gear your 3.2 or 3.4 would reach the same speed...because your transmission and final drive ratio is the same. Redline is the only variable here, I would assume 3.2S motor can rev a littler higher, so few MPH more in each gear. Acceleration will tell you want you want to know performance wise. Get a g-tech pro and record some 0-120MPH runs or take the car to the drag strip and do a few passes. Your 1/8 time will tell you how far off pace of a 3.4 you are.

Top speed will be slightly less but not by much. As others said, engine displacement doesn't matter, the transmission does and since you didn't change it, all will remain unchanged.

Yep you're both right. I don't have any experience with measuring hp so this is a learning curve. I was only looking at velocity and what i needed to know was acceleration. That GTech-Pro looks pretty sweet.. thanks! The top speed is usually limited by the HP required to overcome the increased drag at those speeds right.

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Exactly, technically I could take my tall geared CRX HF with a fraction of the power and eventually get to similiar 71mph around 7k rpms too. This only indicates gearing ratios and nothing else. Since this is a budget build, I would suggest one of the many HP/Acceleration apps that are available on Smartphones if you have one. It doesn't really make sense to spend over $100 vs. $5 that do the same thing, especially if you are only going to use it a couple times.

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...however the power and torque are significantly less on the 3.2l unit which came from a car with a taller final drive. I think you might find 6th gear in the Carrera a bit too much for the torque available from the Boxster engine. My guess is that you'll be speed limited to a maximum of around 150 mph. There will be a bit of a negative impact on acceleration too.

6th gear feels great in the 3.2 I don't know what you mean by "a bit too much" All gears ride and feel very comfortable. This is kinda why I'd like an independent review.

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The final drive of most sporting cars is designed to achieve maximum vehicle speed at revs for maximum power. The 3.2l engine comes out of a Boxster which has a higher final drive than that of the Carrera. This means that the wheels will turn slower in the Boxster at a particular engine speed than in the Carrera allowing the engine to achieve revs for maximum power. When you put the engine in a Carrera with a lower final drive ratio the engine will not have enough torque to allow the engine to rev to maximum power. The car will feel fine in 6th gear until you push the limits, at which point the engine will not achieve the 6,400 rpm required for peak power and as a result top speed is limited.

For dangerous theories yours are the tops. Guess Porsche fitted a heated AOS to cars for those rare uses of short trips in extremely cold weather to all engines but then why not block heaters to all engines to account for the few cases where block heaters are really needed? My theory is based on believing Porsche knows what it is doing and believed it was needed and not just for those cars operating above the Arctic Circle. Porsche like all car makers seeks to eliminate the unnecessary so for something to be present strongly reinforces my belief it is needed.

Porsche designs for the masses which encounter all situations and are also contrained by budgets hence the reason why they couldn't or wouldn't build an even more robust AOS if given the chance. Of course you know there are many contraints manufacturers have to abide by(crash, dot, epa, etc). The only cars I know where they went all out within reason are the McLaren F1 and more recently the Bughatti Veyron which both actually lost money on every sale.

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Your theories are becoming inconsistent.

In a recent visit to the Arctic Circle I found most people were driving 996 C4's.

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So the question then is did this support your original theory/hypothesis? I always thought of Subaru's with studded Nokians in that region. Fascinating indeed!

I wouldn't drive a Subaru in the artic circle simply because the AOS doesn't have coolant to it. It's a recipe for disaster. However I am tempted to start a flat bed towing company in the artic circle... http://www.rallysportdirect.com/Grim...rce=GoogleBase

Ok, was working on the 3.2 engine last night. The only problem it has is the electronic oil level sensor is not working properly. I didn't swap this out with the old engine but finally did pull the old one (that I know was working fine) and swap it out in the 3.2 engine. Funny thing is that the sensor, that i know worked in the other engine still does not work. When turning the key on the dipstick gauge flases on momentarily then goes straight to the clock. Is there a way to reset the system? Oil level on the dipstick is perfect and has been since install. I did a search and someone else had the same problem in a 2002 C2. https://rennlist.com/forums/996-foru...-replaced.html

Just an update. 5,500 miles on this engine swap. Runs great. Oil level sensor only works after getting gas for some reason instead of every time the car is turned on. work done since the swap 1. o2 sensor change 2. having that hard to fuel the car issue. Time to change the fuel vent valve on the filler neck. 3. rear engine mounts. overall happy camper

I just found this thread thanks to your update. Hats off for doing it, especially since it's your daily driver. I'm glad it turned out well If my 3.4 blows up I'll do exactly the same!

POP goes the M96 : ( Threw a rod... Well thats 2 M96's down without a single IMS failure... Contemplating rebuild or if anyone wants it AS-IS let me know.

Your 3.2 engine threw a rod? Damn.

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There is a hole in the block? What are you looking to get for it as-is?

May I ask what was the cause for the rod knock on the original motor? Mike

Yes the 3.2 engine threw a rod.. its still in the car but when I pulled the oil plug I had a huge Don King, then pulled the oil pan cover and found a rod in the bottom of the oil pan along with about a pound of metal chunks. It looks like it was cylinder 2 and I noticed part of the cylinder wall in the debris.. so im thinking either rod bearing failure or a D chunk that caused the rod to break apart. I thought a D chunk failure on a 3.2 would be unlikely. Luckily the rod was contained in the engine. (no hole in the block) The rod knock on the original motor was a factor of the rod bearings going bad... not too shabby a life for a high performance engine with 150k miles.. but to put a 3.2 in with thicker cylinder walls I thought that my reliability would go up. FWIW, I only used Mobil I 0W-40 oil... thinking it would minimize wear on the bearings. ... Imo - 7k would get me seriously thinking but I don't want to get in trouble for talking in the wrong forum about that.

You don't know the history of the engine. Could have been damaged before your bought it.

Amille, check your PM.

Are you selling the car or not?

a 3.2 into a 996 ... well done OP, well done ... <slow golf clap>