3.2 S engine swap into non S 2.5, need help

[Rixter]

I have a customer that wants to swap an '02 3.2 S engine into a 98 2.5 that blew the motor. I have spent hours searching here for the correct writeup (not a 3.4) ... he swears he saw the DIY on this site. I would be most grateful if someone could point me to a good walk-thru on this procedure.

Much thanks in advance.

Rixter

[rsfeller]

I just read this over the weekend, it's 2.7>3.2, so not exactly what you want but has a few good comments from Loren and others who most likely can point you in the right direction. Send anyone there who sounds like they know what they are talking about a private message.

Donate a few dollars to the website and I'm sure Loren (website owner) would be happy to give you personal attention!

EDIT: Also: http://www.renntech.org/forums/index.php?showuser=4060

Edited July 8, 2008 by rsfeller

[mikefocke]

But a 2.7 to 3.2 swap may be using the same DME

which changes things compared to swapping an E-gas engine into a non E-gas car...doesn't it? Wiring different, IIRC.

Look for posts from tholyoak here as he has swapped about a half dozen engines into his car and probably knows more of the ins and outs of the process than anyone.

[Stefan]

A 3.2 swap should be very similar to a 3.4 swap. I would start with Todd's (tholyoak) 3.4 writeup but not worry about lowering the engine or adapting the fuel rails.

You will have to deal with the non-egas to egas conversion, which is not covered in Todd's writeup but which is discussed in other threads devoted to that specific topic.

[Rixter]

we already read thru the 2.5>3.4 writeup, it's not much help with the issues we foresee as problems

this is a tiptronic car, since the dme talks to the tranny controller, do I need to use the 2.5 or 3.2 controller?

will the variocam still work?

[Loren]

VarioCam will be fine as they should be the same (VarioCam Plus did not come in until MY02 on the Carrera - DME 7.8).

The 2.5 liter car has DME 5.2.2 (non-egas).

The 3.2 liter engine is DME 7.2 (egas).

You are going from a non egas engine to egas - so either the DME will need to be 7.2 or you would need to take the intake off the 2.5 liter and put it on the 3.2.

[Rixter]

I have both dme's, so that's not a problem. But will the 2.5 intake actually fit on the 3.2? I think that using the 2.5 intake/dme would be better as it would communicate with the tranny without any modifications/flashing etc.

[Loren]

That might be a little more restrictive (power wise).

tholyoak likely knows for sure - I think he has tried both.

[Rixter]

so you think using the 3.2 intake w/2.5 throttle body (for cable) and the 3.2 dme would work fine? will the 3.2 dme send proper instructions to the trans? what do I do with the e-gas connector on the 3.2 harness for the throttle?

[Loren]

Todd is the guy to ask for sure - because he has done it.

You might send him a short PM and ask his thoughts.

[Rixter]

thanks Loren, I sent Todd a PM this am, just awaiting a reply I'm a couple hours ahead of him

[tholyoak]

For the sake of others, here is the reply I sent to Rixter.

The simplest way is to use the old 5.2.2 DME to control the 3.2 engine. You do this by flashing the DME with the 996 3.4 program, the maps won't be perfect but they will work ok. You use a cable operated TB. I wouldn't use the 986 2.5L one as it is too small, use a 996 3.4 one. With this conversion you will simply need to add the extra wire, the same as with a 3.4 to operate the second plenum solenoid.

So to summarize, treat the 3.2 the same as a 3.4 except you won't have to lower the engine with the 3.2 manifold. Swap the egas throttle body for the cable one. Use the 2.5L harness as you would with a 3.4 swap and add the extra pin and wire to the DME connector to actuate the secondary plenum. Reflash the original 5.2.2 DME with the 3.4 maps or get custom DME programming of the 5.2.2 ecu.

This way is much easier than swapping in the 7.2 DME.

If you have found this information useful, please consider becoming a contributing member.

-Todd

Edited July 10, 2008 by tholyoak

[Rixter]

thanks Todd, I will become a contributor..

I do have a couple other questions...

will I have any issues with the transmission and alarm since they are coded to the dme (I will lose this info when I flash it)

[tholyoak]

If done with a PST2 this information is not lost, you simply enter the old and new dme and immob. codes as the same. The tiptronic computer doesn't care.

-Todd

[Rixter]

Perfect... I have the PST2 and PIWIS here

thanks again Todd.. I will do my best to document the procedure w/pics for upload to the DIY section

[Ag_Boxster]

For the sake of others, here is the reply I sent to Rixter.

The simplest way is to use the old 5.2.2 DME to control the 3.2 engine. You do this by flashing the DME with the 996 3.4 program, the maps won't be perfect but they will work ok. You use a cable operated TB. I wouldn't use the 986 2.5L one as it is too small, use a 996 3.4 one. With this conversion you will simply need to add the extra wire, the same as with a 3.4 to operate the second plenum solenoid.

So to summarize, treat the 3.2 the same as a 3.4 except you won't have to lower the engine with the 3.2 manifold. Swap the egas throttle body for the cable one. Use the 2.5L harness as you would with a 3.4 swap and add the extra pin and wire to the DME connector to actuate the secondary plenum. Reflash the original 5.2.2 DME with the 3.4 maps or get custom DME programming of the 5.2.2 ecu.

This way is much easier than swapping in the 7.2 DME.

If you have found this information useful, please consider becoming a contributing member.

-Todd

Perfect, thanks Todd. Rixter is working on my car and I am excited at the possibility of playing with my Fun Box soon. Thanks to all for your help!

[Rixter]

We are making good progress. Currently awaiting a 3.4 throttle body to continue. We have an idea on the 2nd plenum operation that may eliminate the need to hard wire the solenoid, will give an update when I know if it works or not.

[tholyoak]

The solenoid actuation is 1 wire to the DME, and one wire to an adjacent +12V switched source on any red/blue wire. I really don't see the advantage of eliminating the factory DME from controlling the second plenum. You realize the plenum is actuated at ~ 3120 rpm and turned off again above 5120 rpm right? My suggestion is to do it right and run the wire.

-Todd

[Rixter]

double checking everything while awaiting the throttle body...

uh.. which MAF should I be using? PET shows about 6 diff possibilities, should I be using the original 2.5, 3.2 or a 3.4?

[tholyoak]

The non-egas 986 and 996 use the same MAF, this is the one you will use if you are going to use the 996 program and the cable tb to operate the 3.2.

-Todd

[Rixter]

Update:

The car RUNS! :D Runs rough, but it does run (no MAF hooked up, see below)

Sending the DME to Todd for proper fuel mapping, the intake will not align so we're going to need to fabricate one. Other than that everything is going exactly as planned.

[Charlestonboxster]

Update:

The car RUNS! :D Runs rough, but it does run (no MAF hooked up, see below)

Sending the DME to Todd for proper fuel mapping, the intake will not align so we're going to need to fabricate one. Other than that everything is going exactly as planned.

Including the becoming a contributing member part?. B)

[Ag_Boxster]

Update:

The car RUNS! :D Runs rough, but it does run (no MAF hooked up, see below)

Sending the DME to Todd for proper fuel mapping, the intake will not align so we're going to need to fabricate one. Other than that everything is going exactly as planned.

Including the becoming a contributing member part?. B)

This is my Fun Box being discussed, I found this site and turned Rixter onto it as a source for the upgrade. Rixter is not the big bucks owner, but a honorable hard working techy working to provide good service.

I visited the car last Wednesday and spoke with Rixter and told him that I had contributed as an acknowledgement of the help that this site has offered and as a monetary thanks for same. He promised his contribution and I shall hold him to that, even if I have to have him add it to my bill in order for that to happen.

:renntech:

[gmanz]

Rixter, I have been following your efforts closely as I am performing the same swap in my 97. I have the engine in now and it's running, but I'm using the 2.5 throttle body, I realize the 996 non egas is better. What was your source for the throttle body? The car actually does very well like it is my rear end dyno says that it's maybe a bit better than the 2.5 with a bit of hesitation through the early RPM band. I'm also running the original DME as my computer is the early one that cannot be switched to 996. Did you have this problem? If so where did you find your DME replacement?

Thanks for the info.

Edited July 26, 2008 by gmanz

[Ag_Boxster]

Rixter, I have been following your efforts closely as I am performing the same swap in my 97. I have the engine in now and it's running, but I'm using the 2.5 throttle body, I realize the 996 non egas is better. What was your source for the throttle body? The car actually does very well like it is my rear end dyno says that it's maybe a bit better than the 2.5 with a bit of hesitation through the early RPM band. I'm also running the original DME as my computer is the early one that cannot be switched to 996. Did you have this problem? If so where did you find your DME replacement?

Thanks for the info.

gmanz - I got the 3.4 throttle body from a Renntech member for Rixter to install on my car, I tried DC in Rocky Mount, NC but they did not have one, I was going to try LA Porsche Dismantlers next if I had not found this one here on Renntech. We are using the original DME and remapping it to the engine specs. Good luck, we should get together on my next trip up your way (or if you're ever in Chapel Hill)

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