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Title says it all.

My R32 GTS-T is making just over 230 rwkw at 16 psi and it is simply impossible to get it over 5700rpm without loosing traction.

I would really like to redline the car just once or twice...

Would adjusting the EBC be able to get me to redline with traction?

Or would a tune be more the way to go?

Or am I just going to have to accept that my car is too powerful for traction?

Any thoughts would be great. Can't get accurate results using the search function, my apologies.

James

  • Nope 1

lol you need better tyres...

if your having this problem in 3rd or 4th then i'd say you are experiencing a slipping clutch, might sound funny but i know plenty of people who have mistaked a slipping clutch for wheel spin.

We are talking in the wet?? But seriously, if it was going to be a traction issue would expect it at lower revs (as in when it first hits boost) or to require more grunt, unless there is an issue with the car, eg rear alignment. If the car is lowered for example, you suddenly have a HEAP of camber, which means less tyre on the ground, and therefore more wheelspin. A mate has just gone from 240-280 atw in his 180 (with a pretty pathetic LSD), and he is having trouble upto 3rd, but still at lower revs. Have a look at your Dyno sheet, where ever the power curve starts going vertical, that is when you would expect traction problems.

lol you need better tyres...

if your having this problem in 3rd or 4th then i'd say you are experiencing a slipping clutch, might sound funny but i know plenty of people who have mistaked a slipping clutch for wheel spin.

Bridestone Turanzas are shit? Don't think so. They were upper mid range last time I checked.

I spin 1st and 2nd, chirp 3rd and 4th holds.

My clutch aint slippin LOL

The reason I mentioned adjusting EBC (gain etc) or tuning is because I'm hitting max boost too soon and I'll spin way before redline hence not getting maximum power which sucks when you want to blow off that V8.

I had tyres with probably 30% tread front and rear before and lets just say I felt like I was driving on ice.

James

  • Nope 1

well if you're flooring it with that sort of power then you can expect 1st and 2nd gear to be quite touchy so you have to feather the throttle or fit wider tyres?

otherwise if what you're saying is you want to blow off a V8 at the lights then...well you're not chasing top end then, you'd want to adjust the tune for greater low end/mid range for that take off...but seriously if you want to just blow away bogans at the lights then you don't need 270kw to see who can get to 60km/h quickest.

We are talking in the wet?? But seriously, if it was going to be a traction issue would expect it at lower revs (as in when it first hits boost) or to require more grunt, unless there is an issue with the car, eg rear alignment. If the car is lowered for example, you suddenly have a HEAP of camber, which means less tyre on the ground, and therefore more wheelspin. A mate has just gone from 240-280 atw in his 180 (with a pretty pathetic LSD), and he is having trouble upto 3rd, but still at lower revs. Have a look at your Dyno sheet, where ever the power curve starts going vertical, that is when you would expect traction problems.

Ok well yeah that's why I mentioned adjusting the EBC (gain etc) or tuning because I think my power is coming on later than what it should and peaking quicker???

I'm talking DRY ROADS as well.

My rear camber is pretty negative. As in bottom of rear tyres further out than top of the tyre...

well if you're flooring it with that sort of power then you can expect 1st and 2nd gear to be quite touchy so you have to feather the throttle or fit wider tyres?

otherwise if what you're saying is you want to blow off a V8 at the lights then...well you're not chasing top end then, you'd want to adjust the tune for greater low end/mid range for that take off...but seriously if you want to just blow away bogans at the lights then you don't need 270kw to see who can get to 60km/h quickest.

Don't get too excited with the "blowing off V8s" quote - it was merely to illustrate the situation and this situation with the V8 was a rolling drag so high end is more important than low end as the power pand on rb20s go all the way to 7500...no?

  • Nope 1

wow your camber sucks then, I can get to 7K rpm with 290rwkw in 3rd and its just zooms off and thats with really crappy tyres, but with a well setup suspension and camber alignment

get proper suspension setup... oh & tune out wheelspin, thats just funny...

wow your camber sucks then, I can get to 7K rpm with 290rwkw in 3rd and its just zooms off and thats with really crappy tyres, but with a well setup suspension and camber alignment

get proper suspension setup... oh & tune out wheelspin, thats just funny...

Ok...

Granted I have stock suspension and the rears I've been told are shot. Waiting on my BCs to come through...

I'm sorry if I said something stupid but having boost peaking later would mean I get to redline before or at the same time as wheels start spinning, no?

I know you can't tune the wheelspin out but changing the boost settings to have the power put down differently is possible, no?

There is a gain setting on my EBC for a reason, no?

OK so let's break it down bit by bit:

1."Bridestone Turanzas are shit? Don't think so. They were upper mid range last time I checked." Yes, they are kinda shit. Especially ones with only 30% tread left. Street tyres lose a lot of grip in the first 20% of their life.

2. You are hitting fullboost before redline. Thankfully this is the case. You are meant to hit full boost as EARLY as possible. I'm going to guestimate you hit full boost ~4200rpm. If it is higher than this you need a better matched turbo. Increasing your mid-range power is the key to a fast street car.

3. Loosing traction in 2nd gear is normal for a modified skyline. You need to not use full throttle - that peddle is analogue, you don't have to go ALL the way like using the buttons on an xbox. This is called throttle modulation.

5. Throttle modulation. This is more difficult on small engines with lots of boost. It's hard to modulate the throttle to gain traction for every situation when the feedback from the throttle inputs lags behind due to boost lag. Very hard. Usually it's a preemptive guess for any given situation (ie. cool night, slightly uphill, 3500rpm dialled up) that improves with experience.

5. If you are loosing traction in 3rd with 230rwkw then you simply have a poor suspension setup or tyres. These things decrease traction:

a. negative camber, more camber = less straight line traction

b. stiff suspension (less grip, more control)

c. poor tyres (turanza....seriously???)

d. old tyres (the amount of tread only gives an indication, and mostly of wet traction. Age/number of heat cycles/absorbing grease from road are more important)

e. rear cradle alignment (see "pineapple rings").

Edited by simpletool
  • Like 1

Ok...

Granted I have stock suspension and the rears I've been told are shot. Waiting on my BCs to come through...

I'm sorry if I said something stupid but having boost peaking later would mean I get to redline before or at the same time as wheels start spinning, no?

I know you can't tune the wheelspin out but changing the boost settings to have the power put down differently is possible, no?

There is a gain setting on my EBC for a reason, no?

You could run less boost at lower gears. This is common on newer cars with turbos. I think the Apexi AVC-R allows this....good luck setting it up.

So you'd run approximately 8psi in 1st, 10psi in 2nd, 16psi in 3rd, 4th, 5th.

OK so let's break it down bit by bit:

1."Bridestone Turanzas are shit? Don't think so. They were upper mid range last time I checked." Yes, they are kinda shit. Especially ones with only 30% tread left. Street tyres lose a lot of grip in the first 20% of their life.

2. You are hitting fullboost before redline. Thankfully this is the case. You are meant to hit full boost as EARLY as possible. I'm going to guestimate you hit full boost ~4200rpm. If it is higher than this you need a better matched turbo. Increasing your mid-range power is the key to a fast street car.

3. Loosing traction in 2nd gear is normal for a modified skyline. You need to not use full throttle - that peddle is analogue, you don't have to go ALL the way like using the buttons on an xbox. This is called throttle modulation.

5. Throttle modulation. This is more difficult on small engines with lots of boost. It's hard to modulate the throttle to gain traction for every situation when the feedback from the throttle inputs lags behind due to boost lag. Very hard. Usually it's a preemptive guess for any given situation (ie. cool night, slightly uphill, 3500rpm dialled up) that improves with experience.

5. If you are loosing traction in 3rd with 230rwkw then you simply have a poor suspension setup. These things decrease traction:

a. negative camber, more camber = less straight line traction

b. stiff suspension (less grip, more control)

c. poor tyres (turanza....seriously???)

d. old tyres (the amount of tread only gives an indication, and mostly of wet traction. Age/number of heat cycles/absorbing grease from road are more important)

e. rear cradle alignment (see "pineapple rings").

Thanks heaps for all the info bro. But...

I HAVE BRAND NEW BRIDGESTONE TURANZAS 235/50/R16 FRONT AND REAR.

Old tyres were some chinese wholesale crap.

Correct I'm on full boost at approx 4200-4300rpm

I guess my main concern was that my car should be able to get to redline before it started spinning but I believe now I'm wrong?

The car drives wicked but not being able traction to redline concerned me. Guess it is my furst turbo haha.

Sounds like I need to get my modulation on :cool:

So, on the weekend i was making around 240rwkws from my RB20 and on a slippery track that had been wet, but still not quite dry I can flatten 3rd gear. In the dry there is absolutely no problem with traction in 2nd and 3rd. 1st is a bit of a challnege, but if i shift smoothly and sensibly to second and then to 3rd no wheelsping whatsoever.

I gave my suspension to a friend a while back so he could track his R32 and whilst i had his Tein HCs or HR or something in my car I would have the same problem in 3rd gear with it wheelspinning. The springs and valving were too high, or just wrong and ride height was way too low at about 325mm....though it looked cool :)

So as others have said, check ride height is sensible, alignment and quality of shocks good, decent diff and tyres and you will have no problem with full throttle power down in 2nd gear with 230rwkws

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