cafe_racer

Hi All,

I got my 4RS out on the track today and wanted to start a thread for people to share their setup changes/learnings.

I will go get mine to a shop this week, however from 1 day at Philip Island I can already feel some rear toe in should help with squirming under brakes. Also the fronts are in desperate need of additional camber. Tyre wear was hard on the outsides and insides barely touched.

So far as downforce I put it into high downforce for the event and didn't bother with low downforce at all. Interestingly the rear vis takes a big hit with the rear wing being in high downforce setting.

jmartpr

Good idea to start this thread.
My guess is that alignment wise will be very similar to a GT4.
the 4RS does provide some additional adjustability but you will need aftermarket parts to get it just right for the track.
Camber plates and rear toe links will be the first upgrades
Aftermarket wheels are also a good idea but in order to change to 19" will need an aftermarket brake system (or you can stay with 20").
I know there have been mentions of 19s fitting with stock 408/410 front discs but the clearance is just too small for track use.
By going custom on wheels you can add the extra 0.5" on the front that the GT3s get but the GT4/4RS don't.
Brake pads and brake fluid is a must also.

GrantG

Current GT3 has extra 1" wheel width front and rear (9.5" x 12") compared to 4RS.

jmartpr

True...was referring to the 991.x gen, which is the one the 98x platform is based on.
9.5" would be too much for the front but 9" is good for fitting 265 tires up front

Roarke

Does anyone know the factory setup on GT4 RS?

cafe_racer

fr

From the manual

Jevi Javi

a regular track setup:
camber: - 3 front, -2.5 rear
toe: + 1 mm front, + 2 mm rear

what about swaybars? From the factory both sway bars are in the middle...

GrantG

From my experience with the 981 GT4, the swaybars on the Cayman platform don't make a very big change to the handling balance (as they do on all the 911's I've owned).

But as a rule of thumb:

Soft front bar helps turn in and reduces understeer at corner entry
Firm rear bar helps rotation and reduces understeer at corner exit

Jevi Javi

bingo, looking to reduce understeer

jmartpr

True...but it's a band aid solution, with some side effects. Better to deal with it with a good alignment and if possible a wider tire up front.

dnimi123

whoa whoa whoa... hang on there have been multiple threads already and 'people' (me) getting lambasted for daring to suggest that Pcars let along the GT4RS need any adjustments or mods at all. They are so well engineered and tested that noone should have to do anything at all to the cars whatsoever under all conditions! Of course Im joking but I do find it funny that this forum will go after some people for complaining about the limitations of these cars and then go right on posting about what they are going to do or mod on the car next. Rant over. Carry on...

Warwick Morris

The GT4 RS comes with some useful track set up information. For example, use the top mounts first to adjust camber before trying shims and if you shim ensure 22mm of thread overlap on the tie rod ends. There's also stuff on the aero thingies and a good tip on oil levels plus a track log book you can fill in so that the next guy you sell to can see that you lied about it never having been on the race track.
As the car runs 100N/mm springs front and rear, it's going to corner a lot flatter than the GT4 45/80 setup.
Out of the box, the car is beautifully setup for fast back road driving with reasonable compliance even on the harder damper setting. If you're using the car for both spirited road driving and track work, I'd be loath to change too much and this comes from someone who probably has one of the highest modded 981 GT4s around. I'll be interested to stay in touch with this thread.

Jevi Javi

lovetoturn

Its 100Nm in front and 140Nm in the rear.

With a 60/80 Nm setup on my car moving the rear bar by just a hole on one side makes a noticeable change in the handling. It is nice to be able to make just one simple adjustment to be able to fine tune the car's handling to your personal liking.

vantage

I’ve read conflicting info in many places that it is 100 Nm all around? Wonder if we can find an official doc to resolve.