thoughts about track rims and tyres

[shimmy]

almost sounds like the et for the BBS CH is wrong!!

[TANKSLAPPER]

really surprised by this. cant see how it doesn't foul the liner or arch

All the above is with cup tyres

I did find differences between wheels. ie OEM BBS CSL wheel ie 19 x 9.5 et27 had a clearance between the wheel and the strut of 7mm, but BBS CH'S 19 X 9.5 et 28 only had 3mm between the wheel and the strut.

[shimmy]

I run BBS ch's 19 x 8.5 x et35 with a 12mm spacer on the front which is = to et23 with no problems at all.

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really surprised by this. cant see how it doesn't foul the liner or arch

[TANKSLAPPER]

what camber though TS?

I normally run 2.25 for the road and 3 degrees on track.

I did find with the increased off set on the 8.5j and running 3 degrees camber fooked the inner edge of the front tyres. I put this down too more movement on the wishbones / bushes due to the increased leverage.

My advice is to keep the wheel close to the strut as possible, but increased the width, this should put less stress on the wheel bearing as well.

The tyre wear was was mainly under hard braking where the deflection is greater.

[shimmy]

I run BBS ch's 19 x 8.5 x et35 with a 12mm spacer on the front which is = to et23 with no problems at all.

The tyre & the wheel was inside of the front arch so 3mm more wouldn't make any difference.

The only down side is pushing the inside of the wheel a further out by 25mm over standard makes the car dart around particularly over bumps as it put more leverage on the steering and it tramp lines more.

what camber though TS?

[TANKSLAPPER]

I run BBS ch's 19 x 8.5 x et35 with a 12mm spacer on the front which is = to et23 with no problems at all.

The tyre & the wheel was inside of the front arch so 3mm more wouldn't make any difference.

The only down side is pushing the inside of the wheel a further out by 25mm over standard makes the car dart around particularly over bumps as it put more leverage on the steering and it tramp lines more.

[shimmy]

Do you think I stand a chance if I put 19x8.5 ET20 in the front ?

so same as standard except 25mm less offset and therefore pushed 25mm further out to the wheel arch. Based on the fact that with 15mm+ spacers the tyre seems to foul the arches my guess is on standard geo you will not be able to do this on road.:bigcry:

You may just squeeze the on with 3 deg neg camber for track work!!:thumbs:

[alexk]

Do you think I stand a chance if I put 19x8.5 ET20 in the front ?

[daniel]

That will be an issue, sorry.

Not good. I thought some people got away with 265/35/19 or even 255/40/18 which are pretty much the same diameter.

[TANKSLAPPER]

Thanks for the feedback. I am going to try with tyres that have 2cm larger diameter which maybe an issue.

That will be an issue, sorry.

[daniel]

Thanks for the feedback. I am going to try with tyres that have 2cm larger diameter which maybe an issue.

[TANKSLAPPER]

Tankslapper - Are those photos with the clubsport coilover? Do you get any rubbing anywhere with the 265/35 tyres

Yes there with KW clubsport coilover. their is no rubbing but I have not been on track yet.

The cup tyre size I'm using is 19 x 265/30

[daniel]

Tankslapper - Are those photos with the clubsport coilover? Do you get any rubbing anywhere with the 265/35 tyres

[TANKSLAPPER]

the 9.5J look spot on, i think you missed a trick not getting 9.5J all round making tyre wear and wheel swap dead easy (although you loose that 0.5 inch of rear grip)

I already had the two 10J ch's, I will test the new 9.5J on the front first then on the back with a wider spacers. If it works I will buy another two 9.5J then I can swap them around.

[shimmy]

So am i correct in saying that the ideal size is 19 x 9.5 et28 all round with 265/30/19 cup tyres???

Look forward to hearing your comments of the extra grip at the front on trackdays. :thumbs:

NO not in my opinion

IF you want one size all round on my car (intrax and camber -2 and -3) i would say that ideal size is 19x9.5J et32 with the 265 cups.

This would put the rubber back to the same point 5mm away from the damper (same as OEM front rim) and give you maximum clearance on the arch. It may mean that it is enough for you to run them on the road and adjust the camber to -2

The et28 is very clsoe to OEM rears et27 and is very close to the arch, a little rubbing on max lock and be very wary on the ring and road with big compressions. Also not sure how soft or OEM suspension would cope as it wil travel further.

Quite a few variables though so def worth borrowing some rims and seeing how they work before you buy

Bedofrd Monday should be my trial with the rear CSL rims all round. (you coming BEalo?)