Correct Spring Length

[mikeyd 13]

on my tarmac rally car ive got adjustable bilstien struts with 220 lb 10 inch springs [2 /14 id]

the problem is i need to lower it but with these springs they come out of the spring seats at full suspension travel!!

do i need 9 inch or 8 inch springs?

[welshpug 1,655]

why do you want to lower it? they sit that high for a reason

[mikeyd 13]

as ive got several smooth tar events soon and its sat higher than my old mk 2 escort forest car !!!

[welshpug 1,655]

they're never that smooth

 

 

Personally I'd leave it as it is, if you go lower on the same spring rate you will bottom out more often, basically run out of damper travel.

 

if you go stiffer you will imbalance the car with the rear spring rates (more understeer and snap oversteer), as well as have a mismatch to the dampers as they'd be designed to run 225 lb springs.

[Cameron 16]

Do you mean they come out of the spring seats at full extension? If so, fit some helper springs then you can go for shorter springs.

[brumster 135 1 Cars]

Short of buying helper springs, the ideal solution is to engineer some 'spring guides' to put into the top of the springs so that they guide correctly into the top seats. Just a conical shape of nylon, or some other dense plastic I guess, would do. As a short-term solution I once used a load of packing bubblewrap, wrapped and taped into a doughnut shape, that I put down between the insert and the spring so that the spring was always centralised over the insert not ideal but got me through an event! Surprised you get this with 10 inchers though, mine were 9's and only just came out at full droop.

[SimonJ 2]

I use a Skip Brown dual rate 9" spring which gives a decent ride height. Probably somewhere around standard or 10mm lower, though never measured it.