Mated to a Euro intake perhaps? Is this another Black28 why bother thread?

 

I hope not! Greg down under has been doing a lot of work on 16v heads and likes the U.S heads w/ bigger valves do to the flow speed of the heads. Maybe more will be revealed!

 

Yes. Greg Brown did it and did a write up in an old issue of VW porsche magizine. I have a copy somewhere in L.A. It works out like this: US 4.7 Ljet car + big valve ported heads, plus MSDS headers = almost 300hp. However, your better bet now days would be to rebuild a set of Euro S heads and put them on. I have a spare set sitting in L.A. that I have never unwrapped.

 

I haven't given up on non stock head options, but as a practical matter putting a lot of effort into port doesn't seem to have much payback. Clean up seems good to do, but starting from Euro S heads it doesn't seem like the heads are the weak link for flow.

 

I've ported and polish the USA 4.5 heads. Pulled 430 HP under boost.

 

430hp sweet!Shows the heads work well with boost for sure. I think I read at some point the intake may be the weak link. Wonder what would happen with a set of us heads and big valves?

 

Nice!