powdrhound

That's correct. I run a tall rear tire and when you lower the car to significantly it will help to correct the geometry with the RS parts. Regarding the parts, yes, I time out parts proactively. Over the years I've been caught many time breaking parts and then struggling to quickly find spares. As such I've accumulates spares for just about everything suspension wise and brake wise including calipers, rotors, ABS modules, etc, etc.

Yes, I know of several guys that are now in a pickle trying to find replacement uprights with no solution in sight.

993GT

wonder if Porsche is doing a part 'revision' on uprights... seems to be a trend, time out the part and reintroduce at a new price

powdrhound

mistermct

It's kind of ironic in my case.. I started with crappy old cars that have no aftermarket or OEM support that need custom parts built just to get them passably fun. Now I'm finally in an amazing platform that needs little to nothing to make it fun aaaaaaand some of the parts are too rare/niche for the OEM to provide. Can't effing win. Moral of the story is make more money and churn through new GT cars instead?

powdrhound

Honestly, I've tracked both the 997 and 991GT cars and they have become more civilized and boring with each newer version. The 991GT3 does nothing for me, less involvement and too video game like. I prefer the analog 996GT cars.. Just me. The parts situation is frustrating but hoarding parts is the solution and an ever-increasing necessity especially if you track them heavily.

rbahr

Hi All,

This is a set of problems I have been thinking about for quite some time now as I have pretty much all of these bits on my car - Most of which is written up here somewhere. Turns out the problem is even more complex as the later RSR allow for dive and squat adjustments, there is a question of rake, spring rate,...

Here is more data...

Ray

powdrhound

So I decided that it was unfair to have the RS suspension rotting in the basement so I ended up installing it on my car. Having had plenty of opportunity to fondle the new pieces, I'm very impressed with the quality and beefy nature of the RS parts compared to the standard GT3 versions which feel downright flimsy in comparison. While at it I also installed a new set of JRZ Motorsport 3 way race shocks with new springs on all corners to round out the suspension refresh. Here are a few pics.

RS rear subframes along with PM 997RSR thrust arms. The forward attachment point of the RSR thrust arms is raised 20mm via different length bushings to provide anti squat geometry.


Here are the rest of the suspension components used with this package: PM 997RSR front and rear LCAs, toe arms, and thrust arms

997RSR upper control arms (aka dog bones)


Front RS uprights. Upper shock mounts visible are PM 997Cup mounts

PM 997Cup caliper studs are used on both the front and rear wheel carriers to preclude any stripping issues.

Backside of the front upright with the air shield visible which helps channel air to the center of the brake rotor. Note the dual pinch bolts on the upright.

I swapped in a short RSR Vascomax trunnion pin into the front RSR LCA in order to lower the roll center slightly. PM makes 3 lengths of these which allows you to change the outboard LCA pickup height by 5 or 10mm. I will note that even though I have 3 hard track seasons on these arms, the monoballs are as tight as the day they were installed. Good stuff...

Front finished up with the 380 rotors/calipers buttoned up

Rear upright. Note the 997RS brake duct outlet used to provide brake cooling. Hubs are custom 300M units used for durability purposes as I have broken several of the OEM hubs.

Backside of the rear upright


Double jam nut arrangement used to secure all toe arms and wishbones to both front and rear uprights

AudiOn19s

powdrhound

Hope to have it running by May. We should start engine re-assembly at the end of next week...

rbahr

Hi John,

I have my setup with as little dive as possible and middle of the road for squat, so the bushings you have on the rear are what I have on the front, the rear for me has the same size bushings.

BTW, how are you measuring your roll centers?

Ray

AudiOn19s

I'd be really interested in reference guides, Porsche or otherwise, on setting roll centers, dive and squat with the new setup. I played around enough with rake and shocks on my setup to have it where I like it but would love to geek out on some reading that pertains to how you make all the new bits and pieces work together as a new system.

rbahr

Hi Andy,

I have been looking for a good 'How To' for the 996 for a while. My reasons for going the way I did was by effectively reducing dive in the front, I keep some of the weight off of the front wheels - should reduce understeer. By leaving some in the rear, helps to 'plant' the car coming out of the corners - not enough data to know if this really works.

I have been considering buying some time with a proper chassis guy to help setup the car, since the car now has 12 different adjustments per corner, and as you pointed out, needs to be treated as a system...


Ray

powdrhound

pete95zhn

Woult it be possible to use 997 Cup's rear subframes? They seem to be milled like 996 GT3RS's ones and both upper and lower control arms are interchangeable with 6 and 7, bushingswise at least.

EDIT: Possible or not, I just bought a set of 997 Cup/R/RSR subframes. Let's see how this ends, once again...

rbahr

Hi Pete,

It should work - just be careful as they were really widening the track on the RSR's

I am using the 996 RSR parts, and they work fine - both uprights and side members

Ray