porsche mania

Don't forget to consider other changes you may have made to the car when fitting the rs uprights like bigger discs and calipers, these will have an effect on front brake bias therefore making it easier to lock the fronts up. The increase in front camber that I put onto my car had quite an effect on how hard I could brake before the ABS kicked in!

TurboIXXI

I noticed my ABS was engaging more often after lowering with KW V3, I was hoping that a set of RS uprights would help this as well. The uprights seem to be on back-order since August.

Steve Weiner-Rennsport Systems

RS uprights, in and of themselves, will not affect your ABS.

You may have other issues with the ABS system.

Vandit

Those having ABS trouble, did you see the discussion on the prior page about putting the 964 ABS gear on the 993 hubs? Did you carry out that change?

mystert

There is a paper I read on this site about lowering and brake upgrades. It was written by Bob Gagnon and Bill Gregory. It talks about lowering the car can change the brake bias therefore effecting the ABS system. Search for it, its very informative.

raffsracing

Thomas, a very good article. You have a way with words.
I too have done the mods, however I used the 993 lower arm. Also the same mod with the tie rod worked for me also. My car is street driven (1993 model year) so i didn't want the added noise of the solid bush type top mount. I did use the standard mount with KW's also so as luck would have it I didn't have an issue with M12 / M14 bolt sizing.
Now I know you will ask me how much camber I run but i would have to check & get back to you.
It does feel really well planted on the road & I believe $ well spent also.

Rioja del 73

Sorry I did not find the right answer and solution...
Still do not know which of the parts need ti be changed along with the 993 hubs and abs sensors.
Thank you for your patience.
​​​

Bill Verburg

993 has 48 teeth on the ABS ring and 964 has 45 teeth.

The front and rear ABS rings need to match as do the front and rear calipers

Rioja del 73

Thank you Bill!

Gus

Bill -
"The front and rear ABS rings need to match as do the front and rear calipers"

What do you mean here by "as do front and rear calipers" - Front and rear calipers are different sizes???
ABS rings need to be same front and back - but calipers???

Bill Verburg

On a stock 964 w/ 4pot rear calipers the front and rear calipers have almost the same external dimensions, the do have the same mounts but the fronts are ~4mm wider, internally they have different pistons 36/40mm front 28/30 rear

On a 964 RS the front claiper and rotor are much bigger, the rear calipers are the same externally as on a C2/4 but they have 30/34mm pistons to help bal;lance the bigger fronts.

on a 964t the fronts are the same as 964RS, the rear uses a caliper that has the same pistons as the RS but is ~2mm wider than and RS or C2/4

jevvy964

Just going through this myself, pic below might help clear things up a bit.



Top set are 993 and show the hub, and both sides of the (separated) ABS ring.

Lower set are 964 and again show hub with both sides of the (separated) ABS ring.

You can see that the top set of abs rings have a smaller lip (polished part of very top right item) to fit inside the actual hub compared to the lower set which have a larger lip which only locates into the inner race of the bearing instead.

Further measurements have shown that the hub/bearing/abs ring have virtually identical sizes but it makes sense to use the later config from the 993 which means moving the toothed ABS ring from the 964 part to the 993 part.

Another pic showing the parts side by side:

wprater

Hi,

I just finished this same complete upgrade and basically did all of Oleg's writeup/improvements for 993/964 suspension! Im getting mixed results on my driving experiences that seem to contradict your review in the first post. This may warrant a new thread of it's own, if you all agree then I will do it.

I've had the car back from a corner balance and alignment and driven for about 400 miles. A few things I've noticed:

1. The steering is quite stiff and hard to turn compared to previously. Everyone that has driven the car has commented on it. I've got the 993 longitudinals mounted so the track is wider than stock 964 and have 225 tires installed.
2. May castor (or something similar seems off) as the steering will hold in a turn, is this common? It doe snot re-center back at all.
3. FL wheels seems toe'd out (visually)

I just had the shop re-check their work and they said the adjustments are still fine and only fractions off.

Here is the final setup

LF
Weight: 612
Height: 125mm
Camber: -2.2
Toe: .10

RF
Weight: 588
Height: 125mm
Camber: -2.2
Toe: .10

LR
Weight: 989
Height: 235mm
Camber: -2.1
Toe: .15

LR
Weight: 912
Height: 235mm
Camber: -2.1
Toe: .15

Here are some photos (because, why not )