imo, anything over 400whp I'd switch out of the .63 just to be safe.
But in Buick land, physics don't apply.
Surprised know one hasn't made 700hp with 44/49 w .63 in Buick land .... with someone fudging the numbers behind the dynojet. lmfaoooooo
I run xxx with a tiny turbo and housing but im NOT gonna tell you my car is 1000# lighter than stock.hahhaha