Hello there to everybody. Found my way here thanks to Jasper so blame him if I upset anybody!

I've actually got a Westfield for my sins (and a Caterham so I'm a well & truely confused individual ) which I'm currently transplanting a ZX9RC2 lump into. The car has Westfields' irs set-up using an English diff the highest ratio you can get for is a 3.54:1.

After doing my sums I've found that the top speed with 13" ACB10's fitted will be 115mph ish, not high enough for what I want to do. Bigger wheels will help obviously, but can I ask what other diffs people are using out there?

Regards

3.89
15" 60 profile tyres
blade engine
127 top speed.......

Jon

I run a 3.89 with 185/60 13's so mega low geared, tops out at about 105mph .
If you want higher than 115mph then you're going to need to go for bigger wheels, the only problem with 14" or 15" wheels is that performance tyre choice seems to be more limited, and those that you can get (A032s etc) are over twice the price of the same tyre in a 13" flavour. What tyres do you run Jon?

Chris

Hmmm. Thanx 4 the replies. Just out of interest, what RPM does the blade rev to?

12600 ere, had a bit o work done though....

tryes, ecpect to pay £100+ for A032's, still running pirreli as fitted by ford....they don't grip....Jasper .....?

Thats the thing, my A032's on 13" wheels were £50+VAT (from George Polley)!