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Cusco Comp S

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Sydneykid Grand Master

Sydneykid

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Hi guys, on the R32 GTST circuit race car we run 400 lbs per inch (7.25 kg/mm) front springs and 250 lbs per inch (4.5kg/mm) rear springs. That's on very smooth race tracks in the dry, on rough tracks or in the wet, we run up to 20% less than that.

The job of the spring is to hold the car up, absorb the compression loads and allow extension to make the tyre follow the road surface. Too high a spring rate lessons the tyre's contact with the road. It is not the job of the spring do other things, like limit the roll, that's the job of the anti roll bars. Likewise, it is not the job of the spring to limit the front end dive under brakes or the rear end squat under acceleration, that's a job for the anti dive and anti squat suspension geometry.

That's the main reason why I personally am not all that keen on Japanese suspension kits. They try to do everything with the spring and damper rates. They do that to such an extent, that I can't even use their road suspension on the circuit.

Hope that helps

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edgasket Contributor

edgasket

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Cheers Sydneykid, it's all good :(

so what would you reckon would be the best rates for road use, I don't mind a bit of firmness but the way it is now it's going to wreck the rest of the suspension. Maybe 270-300lbs for the front and 170-190lbs for the back? you probably have much better anti-roll set-up than me ( i assume mine is still standard ) so I may need a strong enough spring anyway? am i even making sense???

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