Track Tyres

[Toddy 7]

What is the minimum spring rate front and rear you should use, when using 888 or AO48's on track, to avoid riding on the bump stops leading to less grip?

[boombang 2]

This isn't a scientific answer, but a lot of 205 tarmac rallycars I know run A048's.

 

They have all prettymuch run 225lb 9" springs on front end, and either standard or 21mm torsion bars.

 

Bear in mind a lot of rally venues in the UK have gone now, a lot of "rallies" are held on what's near enough a race circuit. At Rockingham Stages it is a race circuit, and above setup worked ok (bit soft on rear IMHO).

 

We also ran similar specs to above on two cars we took to Nurburgring, both on R888s. Again no problems with riding bump stops.

[niklas 1]

Depends on how fast you want to go. Start out with your current setup and keep track on tyre pressure, tyre temp and tyre wear.

The physics is simple; Tyre grip -> Body roll -> Loss of camber -> Loss of tyre grip.