ga911

I "popped" my engine this past weekend on my dedicated 2001 3.4L C2 track car. Now being a good time to upgrade the power plant, I'd like to go with a new X51 crate motor. I've been informed through Porsche that the 3.6L X51 is a pretty straight forward swap (DME remapping) and also by a very reputable performance shop that a 3.8L X51 swap is also possible with a "box" to adjust for the special needs of the Vario-Cam Plus.

Feedback from those who have done the 3.6L or 3.8L swap would be appreciated.

Thanks in advance.

Paul 996

For the 996 based 3.6 engine (x51 or not) your options are.

1) You will need the DME remapped for the fuel maps to run the 3.6 or 3.6x51 and a box as you put it control the vc plus. (this is what was done for my car a 1999 car and a few others on here that I know of such as JimB's old race car)

2) You could also replace the dme and harness from a car with a 3.6 and then you would have a very stock setup that runs the vc plus the exact same way as the factory did.

As for the 3.8 or any 997 based engine, you need to do a bit of research here. There are a lot of incompatible systems on the newer cars such as the fuel return system and the actual instrument clusters and hvac. A 3.8 can be made to work but it would be much more of a science project in a 996. Nothing wrong with that. But the shop doing the work had better know what they are doing and have some experience doing similar projects/retrofits.

For a track toy car... I would do the 3.8x51 If you want to compete with it stick to the 3.6 as then you can fit into a class and not be bumped up too high.

Good luck.

-Paul

AudiOn19s

details on the engine that expired if you don't mind.

rvklein

If they can put a 3.8x51 in a cayman.... =)

himself

Check with Judd Taylor over in the Racing/DE section. He just did a swap to 3.6 X51 (last month or 2), and didn't need much more than plug the engine in. (I think the shop he used had the Euro map handy - but you'll need to confirm with him).

-td

JimB

I would never discourage anyone from taking on such a project but if I were in your shoes I would build a 3.4 to optimal PCA club racing specs. That will give you a great car that has a market when you go to sell it. Spending $15k on suspension, etc. will yield more than $15k on hp and be much more fun to drive.

If you do make the swap, make sure the shop you work with has done it before. The learning curve can get pretty expensive.

Just my 2 cents worth.
Jim

ga911

Paul - Thanks for the concise reply. You bring up a very valid point regarding classification. I do plan on using it for w2w comp, so I'll guess I'll need to figure out what the best class would be for the final product in SCCA, NASA and PBOC. Can you shed any further light on the subject?

AudiOn19s - I don't really have specifics. On track the engine vibrated bad, blew tons of smoke and quit - luckily it didn't dump oil on the track. My tech says it's done and I'm not going to waste money on an autopsy since I want an motor upgrade.

TD - I read Judd's thread, but I believe he put in a 3.4L X51 - I'm looking at a 3.6L or 3.8L - but it was still an interesting post.

Jim - I've put most of my money into suspension up to this point, I'm just not happy with the 3.4L. Would I be at a huge disadvantage by "classing up" with the 3.6L or 3.8L upgrade?

Thanks - Patrick

Tippy

+996,

especially on Porsche's.

JimB

Patrick,
For racing in PCA you would be screwed with a 3.8L x51. As the rules stand I think you would run in GTA or GT2S/R. You would get killed in those classes. With a 3.6 x51 you would run against GT3s with a similar outcome.

NASA uses a HP/weight formula that rewards great handling, light cars. It's always better to decrease weight than to increase hp in these systems.

I'm not sure about the other organizations.

What suspension do you have? Check your wallet. If you have any money in it you don't have enough suspension.
Jim

ga911

Great points. I'm attending a PCA (DE) this wekend at Road Atlanta - perhaps I can find a knowledgable member to discuss classing with.

Ajustable coilovers w/ camber plates, GT3 bars, adjustable drop links - yes there is always more and better - but to this point I've foucsed on suspension before other modifications. My initial path was to buy an older Cup car and sell my existing 996 C2. Since I blew the engine, I'm thinking that I can build a car capable of lap times similar to an older Cup but without having to foot the bill for a new Cup engine every 30 hours.

JimB

You can't make your car as fast as a cup car. That I can promise you. I had a pretty fast 996 but my 996 cup was 6 to 10 seconds faster at every track. FWIW, Cup motors last more like 130 hours than 30.

Again, I don't want to discourage you from chasing more power but it doesn't sound like your suspension is even close to optimal. Think full monoballs, 4 way adjustable race dampers, big springs, GT3 control arms, etc. etc.

Analog Theory

I would recommend just replacing your motor with a factory reman 3.4 The X-51 is expensive and for reference, the 3.8L X-51 is upwards of $20K from the factory (we put one in a Cayman). I agree with the other poster's also, setup wins races not extra power. Spend the difference on a proper suspension and put that car on a diet...

ga911

Thanks guys. I need to really investigate this a bit more before ordering the new engine. I'll post an update as the project moves forward.

CWay27

Like others have said, get yourself a stock crate engine for 8-9K and sell it. Then go for an older cup. Those cars are bullet proof.

salayc

Do the 3.8 and take lots of pictures!
I say that only because I want to see how it goes.