Problem With R33 Gtr Wheels On An R33 Gtst

[damuscat]

Hi guys,

I recently purchased a set of R33 GTR wheels for track use on my R33 GTST. Rears are perfect. Fronts.. no so perfect.

The problem only occurs with the front passenger side wheel. At full lock to the left the inside edge of the wheel touches the suspension arm that runs parallel to the shock absorber. At full lock to the right, the front driver's side wheel doesn't have the same issue but it does come very close.

I've checked everything as best as I can and there are no obvious bent suspension components or anything like that. However, by sight I can see that the front passenger side has more negative camber than the drivers side. I confirmed this by checking out my last wheel alignment report.

Front Left: -2 deg 24'

Front Right: -1 deg 42'

I think reducing the amount of negative camber on the left may help but wanted to get opinions. SydneyKid's recommendations on camber for road use are -1 deg (as I found in the group buy kit recommendations).

I'm also getting the front raised. Currently the wheel centre to arch measurement is about 330mm so I plan to raise it by 10mm. That will help solve the typical scrubbing issue but after speaking to a suspension shop on the phone today it seems unlikely that it will stop the rim from hitting the suspension arm.

Spacers have been suggested but I really don't want to go down that path. Someone please help.. I want to hold onto these wheels!

[ferni]

Defiantly get your alignment fixed up, may help. A mate ran R33 GTR wheels on his gtst with no problems i'm pretty sure.

[damuscat]

Yep, the alignment is going to get a look hopefully this weekend. I really hope that fixes it because other than that everything looks okay.

I also know someone that's run the GTR wheels without issues on a GTS-T. The only difference was that theirs wasn't lowered.

I don't exactly have my car lowered alot... rears are 350mm, front about 325-330mm (wheel centre to top of arch measurements). I'm having the front raised to at least 340mm. If I measure from the floor to the bottom sill the back end is about 20mm higher than the front so after I raise the front it should make the drop about 10mm (which is supposed to me more ideal from what I've been reading).

[Sydneykid]

Yep, the alignment is going to get a look hopefully this weekend. I really hope that fixes it because other than that everything looks okay.

I also know someone that's run the GTR wheels without issues on a GTS-T. The only difference was that theirs wasn't lowered.

I don't exactly have my car lowered alot... rears are 350mm, front about 325-330mm (wheel centre to top of arch measurements). I'm having the front raised to at least 340mm. If I measure from the floor to the bottom sill the back end is about 20mm higher than the front so after I raise the front it should make the drop about 10mm (which is supposed to me more ideal from what I've been reading).

The best height for handling and ride comfort in a GTST is 350 mm front and 340 mm rear. That gives ~10 mm rake (nose down) at the sills.

I am not sure that adjusting the camber will help. The relationship between the upright and the wheel doesn't change much when you change the camber. Caster might be a better option, see what the wheel alignment reveals.

Cheers

Gary

[damuscat]

The best height for handling and ride comfort in a GTST is 350 mm front and 340 mm rear. That gives ~10 mm rake (nose down) at the sills.

I am not sure that adjusting the camber will help. The relationship between the upright and the wheel doesn't change much when you change the camber. Caster might be a better option, see what the wheel alignment reveals.

Cheers

Gary

Hi Gary. I've read your recommendations before but there must be something weird with my car. I took some measurements the other night and this is what I got.

Front Left: 330

Front Right: 330

Rear Left: 350

Rear Right: 345

Rake: ~20mm nose down.

...so taking your recommendation to raise the front to 350mm (up 20mm) and lower the back to 340mm (down 10mm) it sounds like my rake would be 10mm with the nose up.

My measurements may be a little out but I even turned the car around and re-measured just in case the surface I was on was a little uneven and throwing things out.

I should also mention that I have the sub-frame bushes in the rear. They're currently set to the "middle" setting (can't remember what the proper name for it was).

Edit: I just realised that a 10mm adjustment (measured from the wheel centre to the arch) won't necessarily equate to a 10mm difference when measured at the sill next to the relevant wheel. So my final rake calculation of 10mm nose up is probably out.

[MrStabby]

...so taking your recommendation to raise the front to 350mm (up 20mm) and lower the back to 340mm (down 10mm) it sounds like my rake would be 10mm with the nose up.

Note SK said "at the sills". Compare the top of the wheel arch to sill at the front and back. I'd imagine they are 20mm different, hence why its 10mm nose down.

[damuscat]

Well I've just been out conducting a little experiment. I jacked the car up slightly in the front centre so that from the middle of the wheels to the top of the arch at the front it sat at 350mm (a 20mm increase from the height it was).

Raising the front slightly seemed to make the back squat just a little as on measuring the rear it was 340mm (down from 345-350).

When I measured the rake with this setup it was about 5mm (nose down).

Thanks for your suggestion Adam (I only just realised what you meant). I'll check that out tomorrow and see if there is a 20mm difference.