Feralc

my anti roll bar setting was not changed, so whatever the stock is, it is what I have now
So a difference of 1.3 between F and R camber is not too much? According to the OP the difference should be closer to 0.5

m3bs

I run 3.2/2.2 with 265s up front, primarily on track. I concur with the suggestion to soften the rear bar. Mine feels much more planted on corner exit than in the stock position. The camber spread has a minimal effect.

milrad

Less difference would be marginally better, and .5 difference is a good target. On the street, you are more likely to have tire wear issues though than ultimate grip. On my track car my difference is 1.2 degrees.

However, if you haven't even tried different ARB settings yet, to understand the impact, you are just wasting time and money. There is a reason they are adjustable, and its easy and quick to do.

Feralc

whats the stock setting for the anti roll bar?

milrad

Medium front and rear

Feralc

so the general consensus that the 981 GT4 is better with hard on the rear and medium on the front is because the car tend to understeer from factory and maxed out stock front camber wouldn’t go over -2??
so now that I have the shims and I am at -2.6 I need to do the exact opposite to compensate that over correction?
would you soften the rear and keep the front medium, or would you go hard on the front as well?

Phokaioglaukos

Could use some advice on a shim package to assemble. Mild setup now and perhaps more aggressive later, whatever that may prove to be. Thinking four each 1mm, 3mm and 6mm, but thought you may have some advice based on actual experience how much is typically used.

milrad

There are too many variables (tire compound, tire pressure, ambient conditions, surface conditions, etc) for a simple answer. However, I'm in the camp of, "if you are pushing the car hard enough on the street to detect these subtle differences....." So you already know the rest of the "lecture."

Track alignment sucks for the street and vice versa. It's not really clear what you are trying to accomplish.

That said, if you are happy with the front and feel the rear is too loose you can 1) lower your rear tire pressure, or 2) soften the rear bar one or 1/2 setting. Leave the front alone unless neither of these changes help. Only do one change at a time.

Are you running with your suspension in "normal" or "sport?" Have you tried the other, and what was the change?

I respectfully suggest you try learning the limits of the adjustments that come stock with the car before you start throwing money at hard parts to get to some "consensus" set-up. But what fun is that ?

Feralc

usually I drive the car on the normal suspension setup, the sport setup is too stiff for the tracks I go to (Chuckwalla, Streets of Willow) there’s a road near Julian that is recently paved that is smooth as a nice track and I only select sport suspension right there and I really enjoy it. I don’t need to go crazy fast to enjoy myself on very tight canyons, those tight twisties are so much fun to drive. I don’t like going fast on freeways, that is not fun at all and dangerous. It is more the technical part of it, taking a tight turn at 1.5G is very rewarding for me, and I am not endangering others.

but I want a setup that would be very suitable for both canyons and track.

Feralc

Update I installed the Tarret rear toe links and the locking kit
my new alignment is -2.5F and -2.2R
the car drives PERFECT now on canyons, car never snapped on me. I actually tried to make it happen to see the limits of the car and the warmed up Cup Sport 2 were screeching a bit but car never lost it.
i didn’t change the sway bar settings (still both on medium) after a track day I will adjust them if necessary,
I am really happy with this camber.

aryork

I agree with milrad. I can't imagine pushing the car hard enough on the street like you describe. Is there runoff room? What happens if you spin? My mind is thinking of two-lane roads with trees or embankments up and down. Like this: https://www.motor1.com/news/542536/f...h-tail-dragon/

Anyway, glad the settings work. I just updated my alignment to -2.75 and -2.25 and took 2 seconds off my time at VIR. Also changed rear sway bar from med to hard. I read where some folks will just move one wheel position one hole as a 'half step' but I did not try that.

Phokaioglaukos

Curious if there is new info on Tarret vs TPC. I thought this thread ended it: https://rennlist.com/forums/gt4-spyd...e-links-2.html. Post 24 is from my son-in-law.
Also there is this thread: https://rennlist.com/forums/gt4-spyd...acing-gt4.html

Am I out of date?

On a related topic, what thickness of shims are you finding necessary to get 2-3 degrees camber in the rear?

Feralc

you can’t push it as hard as on track obviously but it gives you a good idea of the handling, several roads down here in the San Diego area that are amazing for canyon carving (yesterday I did Palomar Mountain east grade and south grade) South grade has so many tight switch backs that you don’t need to take that fast to pull 1.4-1.5G so if you lose the rear is pretty manageable, usually I try harder on the right turns as I have more room obviously. And there’s rarely someone there as there’s nothing on the top of the mountain (but an observatory)
Now I feel confident the car will be more balanced next time I take it to the track.
My tire pressure was around 33/38 hot that according to Michelin is the when the Cup 2s have the most grip.

And talking about tire pressures, usually I drive to the tracks (3-4 hrs on freeway) the shop recommended me to increase the tire pressure on the tires to avoid uneven wear due to the camber, and then obviously bleed the tires at the track.
if you guys do that what tire pressure do you use?
thanks