OK, i'm ready to buy JIC FLTA2 coilovers for my 350Z, but i noticed there are 2 different sets...

1) Spring Rates:
FR: 560lbs/10.0kgf
RR: 560lbs/10.0kgf Progressive Rear Springs
part #Z33FLTA2S

2) Spring Rates:
FR: 560lbs/10.0kgf
RR: 672lbs/12.0kgf
part #Z33FLTA2H

Does anyone know the difference? what difference would a progressive rear with a higher spring rate do? Which are better? Pros and cons of each? Any help would be greatly appreciated, because i'm looking to buy these ASAP. thanks!

 

The progressive rear is more streetable and was initially designed for the G35C. If you track your car, then you'll want to stick with the linear spring.

 

is the valveing the same in the rear dampners for the linear and progressive set up? I've been seriously considering swaping my progressive springs for linear. John: i've noticed you've been through some sagas with JIC so i was hoping you could answer this.

 

just called JIC. turns out that valving is different for the linear and progressive set, and that swapping out just the rear springs is not an easy task. they said it would be better just to get a whole seperate rear assembly.

That sucks because i wanted to swap out my progressive rears with linears, but it looks like a no go... should have stuck with the linear set in the first place, but i do hear from FLTA2 owners that the linear setup is WAY too hard for our cars.

 

Yes the valving is different. Glad JIC has finally figured their own products out now as when I ordered, that wasn't the case.

Again, allow me to reiterate, unless you track your car, don't both w/ the linear springs. Just not worth it - they're stiff as hell and not condusive for any road that isn't perfectly flat and smooth.