R32 Gtr Time Attack Suspension Setup

[emilio_bro]

Hey there. I know this has probably been discussed many times before but I would like a bit of feed back please .

I have a 32 GTR that i use for time attack and sprint days. Recently I just got a wheel alignment and corner balance done and the car now has some extreme over steer happening. So much so that I can barely put any power down in a corner. This brings up my question. What is the ideal track setup for a 32 gtr with street tyres (Federal RSR).??

My set up is: HKS Hipermax IV coilovers.

Adjustable front camber arms

Adjustable front castor arms

Adjustable rear camber arms

Hicas lock bar.

Run about negative 4.2 degrees of camber and 6-7 degrees of castor up front

Rear is about negative 2degrees camber and neautral toe setup.

Thanks in advance. Emilio

[XKLABA]

What's your budget ?

How good do you want it to handle ?

4.2deg is to much on any tyre, about 3-3.2 is good

Is your rear sway bar adjustable ?

Soften the rear shocks and sway bar a bit and see what happens

Personally I like the race spec Teins or Bilstien

[emilio_bro]

So you think the camber should be backed off? The rear shocks are at the softest setting. . They are new coilovers. I currently don't have adjustable sway bars

[MrStabby]

If the alignment caused problems, get that undone. Around -3 camber is what you'd use for R-specs, so is too much for S-specs like RSRs. I'd start with -2 and see how that goes. Measure the temperature across the tread inside to outside to see if its even. 6-7 castor is supposed to feel great but you'll destroy your upper control arm bushes pretty quickly... -2 camber on the rear is probably too much as well. If you can, post full alignment specs before and after.

R32 attessa sucks balls in stock form - too much power oversteer. Get an attessa tweaker if you dont have one already.

[XKLABA]

If the alignment caused problems, get that undone. Around -3 camber is what you'd use for R-specs, so is too much for S-specs like RSRs. I'd start with -2 and see how that goes. Measure the temperature across the tread inside to outside to see if its even. 6-7 castor is supposed to feel great but you'll destroy your upper control arm bushes pretty quickly... -2 camber on the rear is probably too much as well. If you can, post full alignment specs before and after.

R32 attessa sucks balls in stock form - too much power oversteer. Get an attessa tweaker if you dont have one already.

Ahh yes that's right RSRs are an S compound, 2/2.5 on front

Rear depends on suspension bushes use, you need more for rubber then you do for rose joints

As for the Attessa, get the tweaker as Mr Stabby says and do the transfer case mod using the 33 preload setting

[niZmO_Man]

Weak ATTESA? Got the diffs done?

[emilio_bro]

The rear diff has recently been done and the front was pulled apart and checked etc when the motor was built. About 6 months ago. Basically I use to run about -2.5 camber in the front and -1.5 in the rear. But I was having some under steer issues. So I took it to my alignment guy and he put in all this negative

Camber up front so it could turn in better.

The car turns in great now but it's like the rear just can't keep up. It just slides around like nothing

[Duncan]

also I would go less camber at the rear too, I only run 1.5 and that is on semis not street tyres. A little toe in at the rear (1mm) is will also reduce oversteer

When you say extreme oversteer, when does it happen? turning into a corner, mid corner or on throttle application on the way out. How much power do you have, and do you have any diff or transfer case/attessa controller mods?

[emilio_bro]

Well I was running about 430awhp before the alignment and had no issues with putting power down. But ever since I now backed it off to 300awhp and it still does it.

I Know it may be hard to believe but it happens on turn in if I turn in sharply the rear comes around sliding and if I even apply the throttle a little bit more than coasting midway through corners it kicks out and on exit it basically feels like a drift car... I hate how it feels.

Can you recommend any good places that knows how to set up a 32gtr well Duncan? Thanks a lot

[emilio_bro]

I don't have any attessa mods as if yet either. Rear diff is just factory and shimmed/tightened

[emilio_bro]

Also before this setup. I had old single height adjustable ohlins coilovers that had f**ked dampeners. Less front camber. Around (-2.5) and I was doing consistent high 58 around qr sprint track and mid 60. Around lakeside. Yesterday I raced at lakeside and ended the day with a 65.5. So I'm litterally 5 seconds slower.

[MrStabby]

R32s understeer a lot, and power oversteer a lot. AFAIK the understeer is due to the weight imbalance, so can be bandaided over but not stopped. Power oversteer is due to the attessa setup which can be cured with an attessa tweaker (and I guess the transfer case mod mentioned by Mick. I havent had it done, but many swear by it).

I have ~400awhp and no problems powering out of the corner. -3 camber on the front -1.25 at the rear, zero toe both ends, castor will be around 4 40 now (stock is 3 40 so what i would have been running last track day, and i believe the nismo kit gives an extra degree), R spec tyres (r888s). IIRC i was running -2 at the front with RSRs, and wasnt that much slower, but r888s suck.

My latest mods on my car to get rid of understeer are: Nismo suspension arm kit, softer front springs, more front ride height (old springs were too short to get to 350mm). Cant wait to try it out.

[emilio_bro]

By the sounds of it if I just back my camber off in the front to around 2.6 degrees Nd the rear to 1.25 and run zero toe It should work better.

What are the best attessa tweakers? What does everyone use?

[XKLABA]

When they dynoed it did they disconnect the 4WD and if so did they reconnect it, also if the LSD is two way and to tight it can unsettle the rear end on braking turn in which if like me you like to trail brake into corners is fine, if not learn to do it or get a 1.5 way

Bring the front back to 2.5-3deg, closer to 2.5deg given the castor you've got

Rear to 1.5deg and 1mm toe out which will zero out under acceleration but settle the car under braking

Look into some adjustable Whiteline sway bars 24mm front 22mm rear

[datsun_1600]

I would respectfully disagree on going +1mm rear toe out. I would try a little toe in as suggested by Duncan first.

[gtr jet]

I'd be backing the camber off at a minimum and see how you go from there. Maybe back the front off to around 2.5 deg and the rear back to 1 deg.

[emilio_bro]

Thanks for all the helpful info guys. I'll definitely be backing it off and taking the car to someone else who knows more about setting up gtrs. Does anyone know what a good alignment place is around Brisbane??

[djr81]

What sort of sway bars do you have - stock ones?

[emilio_bro]

Yea just stock sway bars

[djr81]

Well there is your problem. Start with some decent anti roll and you will find the cars transient behaviour will improve and that you can balancing the thing up better.