I thought with slicks it's best to upgrade to 31 spline because of the traction?

 

Are you sure you want a spec stage 4? Here is a list of their clutch and specs, get it specs, no pun intended

stage 1 - 410 ft lbs tq capacity
stage 2 - 520 ft lbs tq capacity
stage 2+ - 620 ft lbs tq capacity
stage 3 - 680 ft lbs tq capacity
stage 3+ - 800 ft lbs tq capacity
stage 4 - 680 ft lbs tq capacity
stage 5 - 1100 ft lbs tq capacity


I would imagine you'd need a 2+ or 3, but it's not my build!! Just hate for you to pay extra for something you'll never need so much of.

 

Stage 3 and 4 are identical? Both at 680? I will be at roughly around 600ft/lbs at the fly.
I got that by taking my rwtq+NX 175(at the wheels) then taking out the drivetrain loss.

175+335= 510rwtq
510/.85=600.

680(capacity of Stage 3)-600(my tq at the fly)=80ft/lbs at the fly to work with. That really doesnt give me peace of mind. With this kinda money I'm gonna be shelling out, I'm getting something thats gonna take a 300hp shot if I ever wanted it to. With the wide array of clutchs out there, it makes nosense for a damn clutch to be a weak link. The Stage 3+ sounds good.