Best iron cyl head?

Rob,
The LA-X heads were always Indy. RHS was a partner at first and had both names cast into them.

The LA-X picked up at least 2 tenths over my OEM heads, like a 308 or 587 - all being as-cast with original valve sizes, all else being equal. The LA-X chamber was finished about 4-5 cc smaller than the OEM and, of course, had 1.92"/1.625" valves compared to 1.88"/1.60". I would guess that any mods would be more beneficial on the LA-X than OEM.Just gotta watch the limited installed height and rocker geometry on the LA-X. But if you decide on OEM, a 1.88" valve head would be better start because it can be opened up to 1.92" or 2.02" with fresh, high seats and guides could also be sleeved down to use narrower stem valves. As mentioned by others, pocket porting the bowl and a light port/ polish will help flow a good bit without risking a mistake with more extensive porting.

Getting the TQ tuned right, getting the 4-speed to hook and your limited gear may hold you back. But it should be a fun street car.