[Will]

You want heads with screw-in studs and 2.11" intake valves. You also want an appropriate chamber volume for the compression ratio you're trying to run unless you're willing to dish the pistons you have or buy custom pistons. Achieving a pump-gas friendly mid 9:1 compression ratio on a 400 can be a bit tricky because Pontiac only produced these engines with CRs of 10:1 or higher, or 8.2:1 or lower. Sometimes a small-valve head is a good choice simply because it has the chamber volume you're after. After all, if you're buying all new stainless valves, ARP rocker studs, having hardened exhaust seats installed and are planning on paying for a porting job anyway, then the additional cost to have the pressed studs pulled and the holes tapped for the ARP conversion studs is minimal. At a shop with modern, high quality equipment (Serdi or similar head machine) it should cost no more to cut the intake seats for 2.11" valves than to recut them for the smaller valves, so the price of the valvejob is a wash if you're having all that other work done.

The one thing to watch out for is getting a chamber volume that is too big. The only way to get a good CR with big chamber heads like from a 455 or late '70s lo-performance 400 is to run domed pistons which means spending money on costly custom pistons. In theory, a domed piston doesn't work as well from a combustion efficiency standpoint either. In general, stay away from heads from '71 and later 455s, and 5C-8 or 6X-8 from 400s. Any other large valve, screw-in stud head can be made to work, depending on how much you're willing to spend and what your specific needs are.

Since I don't know what your total combination is (car, gearing, tranny, etc.), how much you're willing to spend, or what "streetable" means to you, I can't be any more specific than that.


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'72 Formula 400 Lucerne Blue, Blue Deluxe interior - My first car!
'73 Firebird 400/4-speed Black on Black, mix & match.