What heads is it running now? What are the best heads to chose for a performance boosted EJ engine build, and don't you need to run the intake manifold and basically the engine wiring/ECU setup from the car matching the heads you use?
I'm not sure what heads it's running now, probably a machined-a-bit: EJ20 EJ25 and DOHC with matching intake... And yeah, you'll want an engine controller if you're changing from SOHC to DOHC.
I just ran the stock EJ22T heads and intake with a TD04 Turbo, so I could get away without tuning it for a while... But the new owner took full advantage of the built block! I think it was a GT30-esque turbo. He says there's some lag, but when it kicks in, it breaks the car loose.
Edit: AND when he did that, he shattered three transmissions within a few months... It's now a STi 6spd... :3
Edited by Legacy RallyGuy, 22 February 2013 - 09:39 AM.