Got my S back after suspension upgrade

[seningen]

Well crap -- took the Box S to my local track and had to replace 4 fillings and 3 ribs....

Ok it wasn't that bad -- but it was damn near undrivable.

My home track resembled a cow pasture when driving at speed.

I have to source some alternative springs --

Does anyone know what spring rate the original Boxster S is equivalent to?

I don't want to go quite that far -- but I can't drive with the 500/650 I have in there now.

thanks,

Mike

[LAP1DOUG]

Originally Posted by seningen

Well crap -- took the Box S to my local track and had to replace 4 fillings and 3 ribs....

I have to source some alternative springs --

Does anyone know what spring rate the original Boxster S is equivalent to?

I don't want to go quite that far -- but I can't drive with the 500/650 I have in there now.

thanks,

Mike

I measured the fronts at about 220 lb/in before I pulled them off the car, Resulting front wheel rate is about 180 lb/in. I didn't measure the stock rear, but would guess they are around 300 lb/in spring. They are progressively wound, so not linear though.

I am running 400 lb/in front / 500 lb/in rear now which works well on smooth race tracks (Barber & Road Atlanta) as well as relatively rough auto-x parking lot course. Good luck.

[Topless]

Originally Posted by seningen

Does anyone know what spring rate the original Boxster S is equivalent to?

Stock springs are roughly 180F 250R
Stock PSS9 springs are roughly 260F/370R [ My car]
Boxster Spec are 450/500

Personally I think 450/500 is too much spring for a car with an open diff and often results in wheel spin on corner exit. Also way too stiff for street use with PSS9s. A more sophisticated dampener may be able to manage stiffer springs.

The voodoo is getting your tires, running weight, spring rates, dampeners, sway bars and driving style all working together to control your contact patch instead of fighting each other. Getting it exactly right is harder than it seems.