Excessive Wheelspin When Boosting Hard

[rondofj]

Hey Guys, just need a little advice here, did some research but couldn't find exactly what I wanted so please dont shoot me down haha..

Car- R34GTT with 290rwkw

Tyres- 235/40/18 Bridgestone Potenza RE040s (36psi) on quality lightweight Jap rims

Suspension - Cusco adjustable coilovers (Blue, would be an older model, not sure which)

Problem - I encounter wheelspin (lasting 2,3,4seconds) when coming onto boost hard from 4000rpms onwards, shifting to 2nd or 3rd and start skating briefly before rocketing forward. I have only recently had a power upgrade from 206rwkw so don't know if it is normal to do this? Even at the lower power level it did use to wheelspin a bit on 1st and 2nd but not third.

My suspension is fairly hard and has very little flex/ bounce when physically pushing down against the boot/trunk esp the rears and I suspect I need softer suspension.

Does anyone has any advice/suggestions? thanks Ron

Edited January 18, 2013 by rondofj

[eightsixboy]

Wasnt there an exact thread like this a little while ago?

Your tyres are fairly skinny (235's) and you have alot of power, I would expect you to loose traction when booting it.

Only way around it is to running wide and sticky tyres on the rear or gradually step on the gas.

[R31Nismoid]

Wider tyres

Softer suspension in the rear

Better rear alignment.

You also have a .63 rear on the turbo so it'll be ramping hard so you might need to just learn some throttle control.

My GTS-R with 280rwkw never broken traction other than the top end of 1st even @ full mash. Good tyres (had 255s on), supsension setup, good power delivery from the turbos/tune etc.

[dori34]

^ same,

unless it was wet lol

get wider tyres, turn the dampers to soft, lower the tyre pressures & run softer spring rates

[Hank Scorpio]

Wider, grippier tyres required, pretty straight forward!

I disagree with what's being said about the dampening, if you're already moving and have GOOD tyres and running < 300rwkw you should be able to run a stiff spring rate and high tyre pressure with no dramas.

I run my dampeners set on full stiff and my tyres pumped up to 40psi and when I'm moving and cracking gate in a straight line I have no traction issues unless I'm being silly with the clutch

Edited January 18, 2013 by Hank Scorpio

[R31Nismoid]

^ different car, tune, turbo etc. Power delivery has a lot to do with it.

So other things than just better/wider tyres might be needed for better overall fix. Always hard to tell but always better to have a few options if one doesnt make it heaps better

[Hank Scorpio]

^ different car, tune, turbo etc. Power delivery has a lot to do with it.

So other things than just better/wider tyres might be needed for better overall fix. Always hard to tell but always better to have a few options if one doesnt make it heaps better

This is true.

But I'd take the same approach as I do when I'm trying to fix a mechanical issue, fix what's obviously broken/farked (in this case his tyres), see what happens and go from there.

[rondofj]

Ahh thanks guys, one thing is confirmed- your all saying I need wider tyres so that would be one fix, I did find that by reducing tyre pressures from my initial 40 to 36psi I was able to get rid of a lot of the wheelspin.. Maybe try 34 and 32 as a final pressure, its 100% street driven so I fear 32 is the lowest I could go.

Nismoid is right in saying the 0.63 rear ramps up hard, the delivery is not linear as on my dyno graph (RB25 thread), Hank also has a very good point that I didn't think of, it 'shouldn't' skate and wheelspin while running because it doesn't squat much (like launching) so the suspension isn't the major problem but could be softened as you guys suggest - it doesnt have adjustable damper rates unfortunately, just height adjustable.

[R31Nismoid]

Harder rear will 100% play a factor in wheelspin.

When I put the power down in the 31 or the GTR at speed, the rear would still squat a little. Having no transfer at can certainly be a factor in wheelspin.

[The Bogan]

Softer front and softer rear springs with some correct shocks, you need the front to lift and the rear to squat and hold there, this will transfer the weight over the rear wheels.

You will also need to run a small amount of positive camber, mine runs 0.5 positive rear at the drags which seems to work well for my rubbish suspension set up..(its not rubbish for the track, its rubbish for the strip)

That is if you want straight line only performance, other wise get some good tyres and work the throttle, not mash it.

0.5 to 0.0 neg camber rear will help but will not be so good in the twisties.

Can your ECU be tuned for boost/road speed.

Thread needs more 3ltr.

[Dose Pipe Sutututu]

toe the rear approximately 1~1.5mm eitherside that helps, get some camber arms run minimal camber.. and 235 with your kind of power would fry tyres, run 265 wide (provided your rear rim is x9)

[Ph@t-G]

Besides the tyres being too skinny for the power that you are making, another question that you should be asking is how old are the tyres?

Even if you're running good quality tyres, if it's getting old and becoming rock hard, then that will only add to your wheelspin problem.

[WMDC35]

decent diff helps too

[Carbon 34]

My s2 gtt with close to that power/ coupe

nismo diff 1.5

Ultra light flywheel

285 18 32 psi good new tyres

Softest setting on the bilstien coilovers , running near flat camber

With pedal feathering near torque peak it will fry the tyres right off if TCS is off !!

if you keep in it mashed it will spin in many gears and be sideways the whole time fun on a track day not driving in traffic

The car does squat down a fair bit and on second it really drops the rear hard on boost

The fix , add fuel , put the spare in

The car acts like a beast with TCS off and no weight in rear end , like a go kart with lots of power

It would sling you into the trees if your not aware every second and oz buppy roads makes it way worse

TCS on its sedated but can rear up ugly if pushed hard or wet roads at speeds above 30ish kph

I just leave mine on to save the tyres and ease carefully on boost in the lower gears

It also saves your license

Its a drivers car not a couch with wheel

So pay attention

[The Bogan]

My birds alfa will spin the wheels if you mash the pedals, its all about good throttle control.

I can launch fairly hard and with good throttle and clutch control get the power to the ground with minimal wheel spin, my tyres are 255, power is a tad over 500 hp.

Do some driver training days and/ or track days and learn how to drive a car with a hi power motor.

Putting down the power is a skill that needs to be learnt.

Otherwise old mate in his 100 hp auto lancer will smoke you.

I'm not taking the piss here, I've talked to people who claim their car will spin the wheels in the first three gears, why, because they just drop the clutch and mash the pedal.

With great power comes great responsibility.

[WMDC35]

/\ , power corrupts, absolute power corrupts absolutely

i'm running average 255s with 1 degree camber & can usually stick it down after 1st (at 340rwkw)

try not to shift too enthusiastically

Edited January 19, 2013 by WMDC35

[rondofj]

My birds alfa will spin the wheels if you mash the pedals, its all about good throttle control.

I can launch fairly hard and with good throttle and clutch control get the power to the ground with minimal wheel spin, my tyres are 255, power is a tad over 500 hp.

Do some driver training days and/ or track days and learn how to drive a car with a hi power motor.

Putting down the power is a skill that needs to be learnt.

Otherwise old mate in his 100 hp auto lancer will smoke you.

I'm not taking the piss here, I've talked to people who claim their car will spin the wheels in the first three gears, why, because they just drop the clutch and mash the pedal.

With great power comes great responsibility.

I dont normally drop the clutch and mash the pedal, when I did a few times all I get is wheelspin as you said. I generally come on the gas progressively and have dropped my 235 18 tyres to 34psi now. Managed to get rid of some of the wheelspin with throttle control, but the thing is if u want to go fast on a track or accelerate hard, then you gotta mash the pedal, no?? Else you will hardly be faster than a v6 commy. Well initially, anyway..

[ARTZ]

geez Ron I'd be pretty pissed if I just built a 290kw car and it didn't wheelspin...

mine sticks like glue with 255/40/17 race tyres and a little throttle/clutch control...however my 235 street tyres spin on command and thats half the fun of it

Theres more to racing than just mashing the pedal mate..Unless you just want to drag race then the answer is simple..your suspension is too hard and you want more fatter softer rubber..

But on a racetrack you will find knowing when to brake, turn and change gears is far more important than just getting power down...Any idiot can get a car up over 200kms its knowing what to do with it when you're there that makes you fast...

As Mark said, do some driver training and report back...

[The Bogan]

geez Ron I'd be pretty pissed if I just built a 290kw car and it didn't wheelspin...

mine sticks like glue with 255/40/17 race tyres and a little throttle/clutch control...however my 235 street tyres spin on command and thats half the fun of it

Theres more to racing than just mashing the pedal mate..Unless you just want to drag race then the answer is simple..your suspension is too hard and you want more fatter softer rubber..

But on a racetrack you will find knowing when to brake, turn and change gears is far more important than just getting power down...Any idiot can get a car up over 200kms its knowing what to do with it when you're there that makes you fast...

As Mark said, do some driver training and report back...

I wish i could just mash the pedal at the drags mate, the boat even on MT drag radials will bag it up, I'm in a state of confusion on trying to get my first half of the strip times down, little by little they are getting better, all I need now is to lose 0.1 of a second and I might get a 10.999.

Hopefully anyway.

Although I do believe I'm nearing the end of the usefulness of my track style suspension when it come to drags.

[ARTZ]

I wish i could just mash the pedal at the drags mate, the boat even on MT drag radials will bag it up, I'm in a state of confusion on trying to get my first half of the strip times down, little by little they are getting better, all I need now is to lose 0.1 of a second and I might get a 10.999.

Hopefully anyway.

Haha or NOS...2 of the big ones...Nah, once you hit 400kw there is no longer simple answers...could you use less boost of the line maybe through the first 2 gears...then jack it up to finish

If I was going to build a drag car I'd be running an auto anyway, it must be annoying you the illusive 10...