Why swap to silvia popups ? Their are alot of local S13's with silvia front ends nowadays, personally i haven't seen you do any REAL performance modifications to your car , it's mostly show and misc interior crap. 1k Worth of front end can buy you a pretty decent turbo , or atleast a manifold+t3/t4. Too many people try to look diffrent, at the end they just all start looking the same.