It is time for the heads on my twin turbo.... can anyone advice me as to what are the options as to who has what and in what ranges?
thank you

 

As in "who ports them"? Or "whats out there in the aftermarket"? Livernois and Foxlake pop off the top of my head, but give the thread a bit and plenty of people will chime in.

My one bit of advice when sifting through the various alternatives, ask the head modifier if they use a 3.55 bore fixture to flow the heads or the more common 4.00 fixture bore.

It easy to get big (but false) flow numbers using the 4.00 bore fixture.

3v stuff looks to top out right around 300 or so CFM on the intake side (plenty of flow with no restriction for an engine that produces 600hp or less, of couse an FI engine changes things a bit in this regard).

Then there is the cam phaser issue (cam phasers dont take well to increased spring pressure).