Been looking at a track set up and thinking about 18" rims and tyres.

Now I have seen a few 18" running on ISF's I am a little more comfortable on running this type of set up and clearing the front calipers.

Got my eye on the following

OZ Ultraleggera's

Front 18" x 8" ET48 running 235 x 40 DOT Tyres
Rear 18" x 9" ET 55 running 265 x 40 DOT Tyres

Any thoughts or comments on this possible fit and trouble i.e. rubbing etc?

Cheers

 

If this is going to be "just" a track setup, then you want to get front and rear in the same size, this will do two things, first you can rotate them front to rear, second, you will help remove a lot of the under-steer (or push) that the F is prone too on the track. p.s. unless you are from Europe we spell tyres "tires" ;-)
Hope this helps

 

^^ %100 agree ^^ 18x9.5 or 9 with 255, 265, 275.. or 19x9 all around with 255s

 

Thanks for the comments.

FYI I am in OZ so the spelling of tyres or tires is correct

The problem I see with running none stagger is the maximum tyre on the rear, fully agree with the comments about understeer but the reverse will be oversteer.

I am no expert but I think understeer would be a much safer situation than oversteer with an undersize rear end????

Will 255 fit all round?
Any comments on the actual fit and clearing calipers etc?

 

What I am using for the track this year is what another member showed which is Enkei PF01's in 18x9.5 with a 45mm offset, tires are kumho v710's size 285-30-18 on all 4 corners. I have NOT found over steer to be a problem unless you are trying to steer it with the throttle (which is NEVER the fast way around a turn). Even with this setup there is still some push in the front end, the front end on our cars is VERY heavy! Hope this helps.

 

i also have a non staggered wheel/tire on mine for a while and it balances out the car nicely. excessive oversteer in not an issue at all, the car just does what you want instead of being a understeering disaster and aiming 3 feet inside of where the car is actually going to end up..

 

Tires tires tires tires tires!!!!!!!!!! Lol

 

285 On the front?

Very interesting set up.

Are you running anything special with front camber to get these TIRES under the guards / fenders?

Photos?????

 

Nope. Look up scca forums on here, he has the exact same setup I copied, and it works VERY well! he has pics and action shots of the car.

 

Yep found that one on here, thanks for the heads up.

 

A little camber and a slight toe adjustment in the front should fix a lot of the understeer you are still having.

 

If only it were so easy...

Camber is not adjustable from the factory. Toe out kills the inside edges of the tires and there's lots of evidence this is true in both the IS-F and 2IS forums.

Many of us have close to -1.0 degrees camber in front from the factory at stock ride height. Adding camber would help, but so would a suspension not intentionally designed to induce understeer by every suspension component.

 

Can you post a link? I have not been able to locate him.

Thanks

 

^^ Right here:

https://www.clublexus.com/forums/is-...k-weekend.html

 

Thanks rhy