You want the EFR 7163 on a decent, tubular manifold for minimum lag. Most dyno charts show this spooling similarly to the factory STI or Evo turbos, but making up to 550 whp. The compressor map is not far off of the EFR 7670 or GTX3076R, but the turbo is much smaller and has much better aerodynamics. The center section is also aluminum for much lower weight.
http://www.full-race...7163-turbo.html

http://blog.perrinpe...-test-and-tune/


The EFR 7670 above also looks very, very tempting...

Tim