BarSundown

Well, I have an 69 XX 400ci engine with ring problems. Since I'm rebuilding, I'm pulling everything off the block and replacing it with new - heads, intake, carb, headers, etc.. Most of the parts I'm pulling off are aftermarket. And, it's not the original engine anyway, so no harm done.

Anyway, the block is topped with a good GM head marked 62 above the D ports. Looks like it might be a 69 Ram Air head, but I'm not sure. Anyone give me some advise?

Thanks in advance...

 

lars

Except for the Ram Air III, all Ram Air Pontiac Heads are round-port heads.

The casting number "62" head was the standard GTO 400 4-barrel Auto Trans D-port head used on 350-horse GTO and Grand Prix, and on some big-car 400s, in '69. It's a 74cc chamber head, producing slightly reduced compression for the automatic cars (the casting number 16 head, used on 350-horse GTOs the same year measured 72 cc chambers). It has the usual 2.11 inch intake valves, 1.77 exhaust, and it has screw-in studs with guideplates.

These heads actually make very good platforms for a good performing 400, since the compression is moderate enough for modern pump gas. The heads can be ported, upgraded with some nice stainless valves, and given a good 3- or 4-angle valve job to produce pretty respectable flow and performance.