Trick Flow 240...

My 470 made close to 720 hp with the 240 heads. That is a pump gas engine. Here is the article from Hot Rod: We Test Intake Manifolds and Carburetors on our 400 Stroker in Search of Ultimate Power - Hot Rod Network

I'm in the process of dropping this 470 into a Duster. The Duster is a bit of a project car so it will be a while before I'm on the road with it.