iron heads for a 408?

sr, Head wise you have what you need, assuming the numbers are accurate. However, the other parts choise will limit output some. The cam is relatively small, good for flat torque, but also good for sharp power drop offs. But with smaller vo,mue heads, I think it is a good match. I would spec a larger carb and intake tho. The 4" arm engines I'm used to that run the std Performer RPM ususally drop off a little after 5500 or so. And drop fast. Also, the carb is on the smallish side. I like wet flowed ratings of 770 or bigger, and dry flowed of 850 or bigger. These things eat up carburetor size. A similar 418 with a set of mildly done RPMS, an RPM, a 3310 Holley, and smaller flat tappet (235/240@ .050 solid) made 450hp/490tq at the crank. It was like shutting off a light switch above 5400 tho. hp peak was 5200.