JBH

Has anyone done the conversion to the n/a 964 Carrera 2 trailing arms in the rear to create more space under the fender (to accomodate a larger rear wheel and tire combination)?

If so, could you give me your impressions: Pros/cons for performance on street and track?

jeff91C2T

Try this one...

http://www.c2turbo.com/forums/showth...&threadid=1895

cobalt

Bad info back when I didn't know what I know today.

JBH

So why is this not a common conversion? It seems to me a simple mod that allows one to stuff a 315 tire in the rear end and a 245 up front would be pretty attractive to this group, but I am having a hard time finding someone who can provide me their experiences.

cobalt

You have a very valid point.

I know the 3.8 RS used the standard trailing arms and used an 11 x 18 version of the speedlines in the rear with almost zero offset. They also ran 9 or 9.5 RSR inch fronts with 235's vs the standard 8" with 225's. I believe, but don't hold me to it, that they used the tubs from the earlier RS's on these and on the euro 3.6T's. The euro 3.6T's were also delivered running 20mm lower than the previous C2T and US spec 3.6T.

emilios

Anthony, turbo 3,6's use different and unique traling arms to any other 964/965, different even to those of the 964 turbo 3,3.

Best regards

Emilios

Adrian

Dear Jeff,
I am afraid it is not a simple modification. You would need to use the ROW Turbo 3.6 components but I am afraid this will require some additional structural modifications. The US version of the Turbo 3.6 retained the MY 1992 Turbo rear end components but the ROW version effectively used the Carrera RS system.
As I have said many times all this is explained in my book.
Ciao,
Adrian
964C4
GT-2

sprbxr

I have a 93 964 and a 91 C2T. I learned a few things from being under both cars for extended periods of time and swapping parts between the two cars.

The control arm mounting points are in the same position on both cars. The mounting bolts are the same. The control arms on the 965 are about 1 inch+/- wider than the 964 arms giving the 965 a wider track. The swaybars are different. The rear bar on the 965 has only a 90 degree bend on each end where the 964 bar loops around making the swaybar link attachment points towrds the center of the car by about one inch on either side. I suspect the axles are longer in the 965 but I did not measure them to confirm this. I also did not confirm the CV joint interchangability.
It looks like a bolt-in swap to me but what to I know.

Adrian

Dear Jeff,
There is a much easier way to achieve what you want. 245s up front might be stretching things but 235s certainly. 315s on the rear I believe are possible.
I have asked for confirmation before I say more but I will say it will not be cheap.
I do not recommend that you go messing about trying to duplicate a Euro Turbo 3.6 or the RS 3.8 on your 964 Turbo unless you do the entire job.
Remember the Turbo 3.6 came with 10 inch wide wheels and the RS 3.8 with 11 inch wide wheels.
The RS 3.8 uses the same trailing arm as the 964 RS which is a different part number to the rest.
The Turbo 3.6 (ROW) and RS 3.8 use the Turbo body/chassis assembly not a narrowbody RS body/chassis assembly.
Ciao,
Adrian
964C4
GT-2

cobalt

Same old bad info

emilios

Anthony, you are welcome to come and drive mine and see for yourself - I would actually be willing to exchange my euro suspension with your color!

Best regards

Emilios

accellracing

I can confirm that the rear suspention pic up points on the 3.3 & 3.6 965 are identical to the 964 as I have converted 964's to 965's. Euro spec 3.3's & 3.6's have identical trailing arms why would US car's be different?. The CV joins on the 3.3 & 3.6 are the same as 964. Can't think why you would want to run 315's on a road car?

JBH

A couple questions then....
What structural mods are required?
If this was a good way to improve handling, why did Porsche choose the US set up that limited the rears to 10"?

I am starting to think that if this was such a good idea, most Rennlisters would be making this change.

Adrian

Dear Jeff,
I cannot answer your "why" questions. The 964 Turbo like yours has the same limitations worldwide.

What do you actually want to do?
You own a 964 Turbo.
Do you want to install the ROW 964 Turbo 3.6 rear end set up?

The trailing arms part numbers for the ROW 964 Turbo and 964 Turbo 3.6 are different. -00 versus -02 for the 964 Turbo 3.6.
What the actual physical differences are; you would need them side by side.

The ROW 964, ROW 964 TL and ROW 964 Turbo use the same trailing arm part numbers except the prefix is changed from 964 to 965 part number series. I have not checked the US versions.

Page 260 of my book explains briefly the differences between the ROW and US 964 Turbo 3.6 rear axle. Other things like suspension are found elsewhere.

The structural modifications include re-inforcements.

If you want to fit wider wheels you just reduce the offset of the wheels you use.
The RS 3.8 11JX18s used 5 mm rear offset if my memory serves correctly.

Ciao,
Adrian
964C4
GT-2

PS: Dear Jeff for some reason I found myself editing your post after attempting a quote selection. I know how this happened and I sincerely apologise. It is just a glitch and is fixed will not happen again.

jeff91C2T

Great info. For all those reading, check out the link in the beginning of this thread for a first hand exerience from Eric on the change.

Regarding the question about why bigger rubber in the rear....isn't bigger always better? Just kidding...

I can say that a slightly modified C2 Turbo can rip through first and and easily spin the tires in second with little turn on the wheel. Bigger rubber in the rear could do a lot at balancing the car out. I'm running 235 front 275 rear and the car is too loose. Too much for tire pressures and sway bar changes to compinsate. Makes for a fun drive in AutoX but down right scary on the track. I can see the need for bigger rubber...