Wheel and Tyre sizes

[gav]

Hi all

If there were no rules on wheel and tyre sizes - what would the optimum set up be for hills and sprints?

The car I have is an ex racer and is currently set up with 11" rears, 10" fronts, a full splitter and large rear wing.

I have the sense that 8" and 10" might be more agile for hills and sprints but would be grateful to hear constructive opinions.

Thanks
Gavin

[Midlife]

I use 7x21x13 crossply slick all round for hills/sprints. Its a plus 2 with approx 50/50 weight distribution, and I find it just right. Suspect that as I get more horses added I will need 8" on the rear.

Another plus 2 that I have seen pushing 203hp has 9" on the rear and 8.2" on the front, at least it was the last time I looked.

Doug

[gav]

Doug

Thanks for that

I should have mentioned that it is an S3 so I dont have the luxury of the plus two wider track and extra length. (although I do have rather large arches to fill)

I will be pushing around 220 horses through a 2L small valve cosie BDA

You raise a good point about whether they should be roughly the same size all round or whether there should be a marked difference between the front and rears.

Regards
Gavin

[Midlife]

Thought I would try and get this thread going a bit...?

What about wet track day tyres? has anyone got any thoughts on good wet radials? for water displacement... I have found this website comparing tyres but there is not allot for 13" http://www.tyrereviews.co.uk/

Anyone use a Yokohama A539 Tyres 175/50/13 ?

Doug

[paros]

Hi
With my old race Elan, I used 13" wheels with 9/20X13 front and 10/20X13 rear - sometimes 9.2/22X13 for a higher top speed at places like Mallory. these were on 10" wide fronts and 12" wide rears.
This was using a genuine 285bhp and something like 220 ft lbs of torque - not a 2000E box or Lotus diff of course for the transmission. Also a modified Spider chassis and about 1350 weight of car.

As to 1b wets, I am told that the 185/50X13 Avon CR28 is the tyre to use, the AO48R is nasty in the wet with no warning before it goes, although the compound is excellent for the wet.

Richard