Hey guys I hope your well,
Quick one I got a Subaru 2.5 Hawkeye WRX just got a VF43 Turbo STI intercooler, Walbo Upgraded fuel pump I want to make about 340/360bhp question is do I do the exhaust manifold (Header) for that kinda power or just leave them?

As it’s going to the garage to have it done I was thinking of doing the hole lot together.
will it make a difference in sound or aswell?

Thank You

 

Not really needed at that level but you could get them ported and a Harvey trick up pipe to assist with spool. All can be supplied by asperformance.