fun2k

can someone please explain what difference in handling these settings will make on a 997.2 gt3:

1. front soft,rear bar mid(current setting) vs front mid,rear hard
2.front toe 0.03(each side),rear toe 0.12(each side) (current setting) vs front and back toe 0.0

The car seems to turn direction very well but once the tyres warmup it seem to get little lazy to steering input?

thanks

997gt3north

If it gets (lazy) I'm guessing your front tires are getting hot (too much psi) or maybe not enough front camber

What are your camber settings?

What tires and hot temps are you running at the front?

The rear toe should really be toe-in (versus your zero toe)

mooty

1. front soft,rear bar mid(current setting) vs front mid,rear hard
===> not much effect. you are moving both car in the same direction, stiffer. you need to drive it to see how you like it. these are minor adj


2.front toe 0.03(each side),rear toe 0.12(each side) (current setting) vs front and back toe 0.0
===> 0 toe in the back is suicidal.
===> .03 and .12 are both toe in. the rear is fine, but why front toe in. i would do zero toe front or even toe out.

fun2k

The front camber is -2.0
Rear camber -1.4

cold tyre temp F29,R31 (michelin) hot between 33,34 - 34,36(max)

thanks for the advice appreciate it.

roberga

I like front -2.0 rear -2.5. I do need to have it streetable so I do not go with more. Here is what mine is and it seems to be a good street/track setting: 0 toe f : 0.17 total toe rear

997gt3north

If your cold tire temps in the front are 29, I'm guessing they are likely seeing 36+ mid session on a 25 minute session (i.e. +7 from cold. If the weather is hot / track is hot and you are 9/10ths, likely all tires can go up +8 to +10 from cold to hot - personally, I think OE front tires are best at 31-32 HOT (thus you are starting 24/25 not 29

I'm also guessing you are going to find front camber in the -2.5 range much better - 996mk1, 996mk2, 997mk1 gt3 owners have all pretty much ended up here for combo street DE day use. Also, since there is so little weight upfront, running more front camber is a little bit of a free lunch in terms of tire wear (versus the rear which starts to eat the inner edges quickly.


may want to leave the bars where they are and try

-2.4front with zero toe (with 31-32 Hot with OE rubber)
-1.8rear with 2mm per side toe-in

fun2k

I noticed the car rolls more now while doing a left then right transition=feels little lazy.This is compared to when i changes the front bar from (one slot below soft to full soft),rear stayed mid.

ic so will going from 0.03 to 0 make a big difference in steering response?
what does less toe in the rear do?is .12 ok for the street or will i get too much tyre wear. i dont do tracking but a lot of spirited drives and i want that race car feeling but dont want to sacrifice my tyres a lot.

thanks for the advice m8 much appreciate it.

fun2k

exactly i need something streetable but dont want it to be too soft either.i want it to feel solid and responsive(the car does that when tyres are cold but not when hot for some reason.i think maybe from the extra tyre grip the car starts to roll more and starts to feels less agile or with the added tyre pressure the camber and ride height is affected??)if i set both sway bars to mid or both hard this might go away but i might get more understeer(just a thought i have no idea what this setup will do).

so the question is how to setup my car for street use but at the same time get that race car handling feel to it.tbh the gt3 feels loose at high speed compared to other sports cars ive driven.

btw what is your sway bar settings?

thanks a lot for your input m8.

fun2k

Actually i havent gone to a track yet.i do a lot ahem spirited drives and max tyre pressure i have seen is 34,36. so i guess 3-4 psi less would be perfect.
Good info on the oe hot tyre pressure ,i also felt when the tyres get to 34,36 the car seems to float a bit.

With -2.4 and 0 toe,will i get a lot more tyre wear compared to my current settings? im ok with my rear grip though atm, the fronts lose traction a lot more often.the rears, only when provoked

btw how do you measure tyre wear?do you look for any specific?

oh and dont ask me why i bought a gt3 for the street,my last few cars did not last long i.e overheating,tyre wear,brake wear,noise when cornering etc..
GT3 is holding up well(after some warranty work done)

thanks again for helping a new guy here.

Serge944

I just got mine aligned to:

F
-2.5 camber
9 degree caster
5' total toe in

R
-2.3 camber
35' total toe in

The car feels great on off ramps, but I'll see how it does on the track next friday.

10 GT3

Keep in mind that tire choices also significantly effects alignment settings. As my car came with Corsas and since I don't have a spare set of wheels I am going to stay with Corsas due to their wet traction, I can be more conservative that if it came with MPSCs. I ran my first 3 track days with stock alignment, which is -1.5 all the way around. Tire wear was surprisingly very even. I could not get enough turn-in, So I went full soft for the front bar.

I just got my first alignment done and I gave them specs on how to set it up. Both local dealers and Ruf all said to keep the rear camber more conservative due to the extra power and across the board recommended -1.8. For the fornt they all gave different numbers. I lean toward high speed stability over fastest turn-in for toe settings, so I stay a little conservative and just keep the front bar soft so it turns in tight:

F:
-2.3 camber
0.0 toe (per side and total)
8.2 degrees caster (10mm shim pack)
Front bar full soft

R:
-1.8 camber
0.14' toe (per side, 0.28' total)
Rear bar medium

Turn-in sharpened a lot. I will be out to try the alinment out next weekend. I will be bringing tools to dial in the anti-roll bars as necessary.

spare tire

Your alignment seems ok. Talk to people with your same car at the track. It is very unlikely that you were give 0 toe in the rear. As Mooty said that is allways wrong for 99.99 % of the time.You are gaining 4-5 pounds of pressure from cold to hot so you are not yet a wild man at the wheel. Just go out and practice late apexes and get on the gas before you reach the apex. the sway bars ajust for oversteer and understeer. (you didn't complain of either)

fun2k

wow mine is pretty similar to your setup except slightly less aggressive.

F:
-2.0 camber
0.03 toe (per side and total)
8.2 degrees caster (10mm shim pack)
Front bar full soft

R:
-1.4 camber
0.14' toe (per side, 0.28' total)
Rear bar medium

Also im running on michelin, do you mean they can handle more negative camber,dont they both have similar tread wear?

also i had the same problem with major understeer when on factory setting so added more neg camber and full soft up front.

btw just out of curiousity what is your ride height.i measured mine from the front bumper and its about 4.3inch off the ground(i know its not a proper way to measure but easier to compare this way).
would reduced ride height make a difference in high speed stability?

thanks for your input m8.

fun2k

sorry i didnt clearly mention in my post,i dont have 0 toe in the rear, was only wondering what difference it would make in the handling dept.

i have yet tracked my car on the road when driving hard max temp was 34,36.
also i have heard if you have less pressure ,the tyre temps increase more rapidly cuz there is less room between the tyre and wheel so it develops more heat??

i was getting lots of understeer with F one positiond from soft, R middle bar position. so changed to F full soft R same as before and its much better now.
if i change to R full hard will that make is more oversteery?

thanks m8.

996FLT6

Do like Mooty- he just have Tony of TCDesign align it wo question unless u are doing the alignment yourself. I'm already confused what u are saying. U setting up for what kind of driving? If only street I keep the understeer. MIke