m3irish

Has anyone had their GT4 aligned yet? Seems you can't get more than -1.5 rear camber before running out of toe adjustment. Kinda lame for a GT car. Is this a 981 issue?

Jooyoung99

Darn. That's not good. What was the factory camber in the front and back?

ExMB

Something appears fishy here. My CDI has a 981S and has more camber than that in the rear. On a German forum they also talk about being able to get more on the GT4.

mgerber

https://rennlist.com/forums/gt4/8723...at-car-14.html

This has a post with the factory settings (which look like about the same at 1.5 front/rear). I was waiting to hear from Nur93 if Manthey was able to dial in the 2.5 that was talked about earlier in the thread. Don't think he has gone to that extreme yet. No idea on my end what the limits are.

Rob VN

My guess is you would have to add shims to the lower control arms like this:
http://www.tarett.com/items/996-997-...m-2-detail.htm

On my 987.1 each mm of shim is worth about 0.1 degree of camber. The GT4 may be similar.

The limit on the rear toe adjustment may be the toe cam adjuster bolt range. The rear toe arms could then be replaced by http://www.tarett.com/items/986-987-...9pr-detail.htm

ExMB

Picture posted on here have shown the rear camber adjustment does not have shimable lower control arms.
Are you advocating replacing components on the rear suspension to be able to adjust camber and toe individually; similar to a CUP arrangement?

Terry L

I finally saw my first GT4 in the flesh (so to speak) and was a little surprised by the ride height. It looks like the car needs to drop at least 10 mm and maybe 20 mm.. Is the suspension adjustable?

jphughan

Yes, ride height is adjustable, and if the GT3 is any indication, it comes at its maximum ride height from the factory. I don't know the range of adjustability though.

m3irish

I'll post the stock specs tomorrow, which iirc, were -1.5F and -1.4R.

To be clear this is not a camber limitation, but a toe limitation when adjusting to higher rear camber levels.

Fwiw, just like the GT3, front camber can go above -2.5.

BGB Motorsports

I'm really confused now. Are you saying that this car does not have split arms??!? After reading 700 articles and correcting people that this thing doesn't have full GT3 suspension, just the lower half, it doesn't have 2 piece control arms?!

I think the OP's concern is that when you want more camber than what's allowed with the eccentric bolt in the rear and you then go to shim up the car for more camber, you can't lengthen the toe link enough to put proper rear toe in the car. The toe link is on the back side so adding rear camber increases toe-out, which requires lengthening the tie rod. If you don't have enough length you therefore can only achieve a certain camber because of your NEVER EVER EVER wanting to run zero rear toe in a Cayman.

In the front, the toe link is in front of the axle line so the opposite happens; increase camber and you have toe-in and again need to lengthen the rod to increase the toe-out to factory specs. Tomorrow morning we have the first GT4 in Orlando coming to the shop. I can give you guys more feedback but I would be utterly amazed if this car has coilovers and not traditional 2 piece arms.

P.S. I would assume the first thing you guys will want in the rear is a traditional 2-piece (3-piece actually) Motorsport style toe link for alignment purposes. Race teams like ours have relied on this setup for over a decade because trying to set toe within a millimeter using the factory eccentric cam lock is nightmare. We can gladly source pairs of these for the rear and you will be good to go for the track and your prep shop or mechanic will love you. You need a 3-piece design with a right and left hand thread and fine adjustment because with the right wrenches, it makes life way easier.

Bonzai30

John - What front and rear camber would you suggest for an aggressive street alignment? I'll be daily driving and tracking my GT4 and, at least at first, will be using the OEM tires on the track. My guess is that I'll track the car 6 - 8 times per year and will put around 4,000 street miles on it each year.

BGB Motorsports

Given the strut suspension, the car likes camber all around similar to what you would have had on the front of a 911 since the rear uprights are essentially front 911 uprights turned around. If a full blown race car runs 3.75FR and 3.25R a 50/50 street or track car could run 2.6FR/2.25R. I'm sure people will suggest tire wear issues but what do you want? Do you want max tire contact patch on the ground all the way through the corner or do you want perfect tire wear for the interstate ride to nana's house? Only you can answer that.

Nur93

On gt4 you can shims front and rear. For aggressive camber the stock toe bars are to short. But you can fit Porsche cup cars longer toe bar to go aggressive camber.




Shims you can do front and rear( pic from My car)

Nur93

My front tire after One trackday, a short twisty One 3km only, this is factory setting on camber/toe. This car need a real setup to work Well. It understeer alot from factory.

BGB Motorsports

There you go! 2-piece arms as expected. You just need a longer toe link for the rear. I think any OEM would catch a bunch of grief for adding too much camber. If you want to go on track, you want a minimum of 2.0 degrees FR/R on a Cayman and that's on your typical 981. Something with a car that is going to use more grip, will want more camber.