I am planning/building a similar 408, with the Eagle forged rotating assembly. I checked with KC about what he uses, and it was Vic Jr. heads, RPM air gap intake, and the DaVinci 750HP carb, which I got from Kieth.
He builds this engine, and I saw a dyno sheet (I'm guessing you could get a copy from him) that said 524.7 Hp @ 5500rpm and 541.0 ft-lb torque @ 4600 rpm. The hydraulic-roller cam he used is the Comp Cams 35-426-8, which I had ground to use the retro-roller lifters, so no reduced base-circle... At .050 lift, the in. and ex. numbers are 236 240, with .555 .576 lift and a 110 degree separation angle.
The RPM heads won't develop as much, since they don't breath as well, but that does'n mean that they aren't a good choice for you.
If I remember correctly, in one of the Ford engine rebuild books they do a 408W based on the bolt-on performer RPM package (heads, cam, intake, and carb) and it produced 410hp and around 430 torque at the crank.
Hope this helps...
