I would like to know if anybaody has used 18 degree valve angle or less heads. If so where did you get them from. Will they fit normal EFI intakes. I was thinking about building an engine with them. I've hearsd these heads make great power, even though they are expensive and you have to buy special valvetrian.
Thanx
Kurt

 

You need a special intake too. Its going to be quite costly to build.

 

I'm running Dart CNC ported 18* heads. You'll need to use an 18* intake manifold, or use spacers between a 23* manifold and the heads. Edlebrock, Dart, GM, etc have several 18* manifolds. You'll need shaft rockers and offset lifters, also the exhaust ports are raised so off-the-shelf headers may not fit in your chassis.

But they do make very good power. My naturally aspirated SBC 427 made 650hp/580ft lbs on 93 octane. On the flow bench the tested out to 378cfm on the intake side, and 260cfm on the exhaust. Low lift flow is very good as well.