I'm getting to the point where I need to be getting some springs for the car. The book states 350lb front 200lb rear. The car's got a big (but all alloy) BMW M52B28 straight 6. In theory this shouldn't be any heavier (possibly lighter!!) than the Pinto the car was designed for but the car will definitely be seeing some trackday / sprint action so was wondering if I should go a tad heavier on the springs? Was thinking 400lb front 225lb rear. I know these may need to be tweaked after but would like to make an educated guess. Any opinions?

Thanks in advance,
Nick

Not sure about that, the wheel frequency is independent of the weight... The ride hight is adjustable via the spring seats.. I would ring Pro-comp for advice if you can't find a definite answer on hear; they should be able to advise and probably supply what you need.

The MK indy uses similar rates (I think the suspension geometry is close/the same.

Dan

[Edited on 2/4/16 by Bluemoon]

My Haynes uses 350lb front springs with 250lb rears although I expect to increase the rears a little as I have eaten too many pies. Its got a Mazda 1.6 engine and box.