Evo 8 ARP question
 

I'm putting my motor back together(all stock). I plan on shooting for 400-450awhp. Should I go ahead and do ARP Main Studs while its apart, or just use the stock? Also should I just use an OEM head gasket? I am using with ARP Head studs.

Mods:
HKS 264s
PTE 1000cc
Walbro 400
FP Ported Manifold
FP Ported Housing Evo 9 Turbo
Full 3" Exhaust
3" Intercooler W/ Hard Pipes

Skip the ARP mains, unless you check the main bores for distortion with the ARP main studs

You should be fine with the OE HG and ARP head studs

So they're not necessary on a stock bottom end? Or would it be at least a good piece of mind for $70 while I already have the crank out?

No need for arp mains unless you start making 500+. Always use OEM mls head gasket no need for anything else. Proven to hold 800+. I would invest in L19 before arp mains.