new power plant

[86cutlass442]

picked up a new 403 its Block has been cleaned, crack checked, line boared, and bored .030 over. Oil restrictors installed in main bearings and studs and straps installed. cranks been turned 10/10, Aires flat top pistons installed on shotpeened stock rods with ARP bolts, Total Seal stard rings installed. Ultradyne cam and hydraulic lifters(specs below). Fel Pro gaskets. Dick miller windage tray, modello valley tray, cranks already in judst need to put pistons and rods in.

my question is what heads should i run?

 

[joe_padavano]

Very nice. You'll need to run the numbers on the true CR, but if your flattops give you a decent CR with the 80-ish CC big block heads, I'd use those. Yes, you'll need to port a Performer RPM to match the BBO ports, but if the C heads worked on the 400 cu in big block, there's no reason why they won't work just fine on a 403.

Alternately, Edelbrocks also work, but of course you'll need to run an electric fuel pump.

 

[86cutlass442]

why would i have to run a elec fuel pump if i got the ebrocks

 

[hunter_alexander]

The ebrocks stick out a little bit on the end by the fuel pump, so you would either need to run a electric pump, or grind a little from the head to clear the mechanical pump (not that I would do that, but I have seen others who have).

 

[hunter_alexander]

And to go into this further, you need to install the pistons, and see how far down in the hole they are. Has the block been zero decked at all? If not, the pistons might be down in the hole 20 or 30 thou from the deck. You need to determine that before you can figure what cc heads you should run to get the compression you are looking for. For pump gas, I would think that you would want to stay around 9.5 to 1 or 10 to 1.

My plan is to run a set of #5 or #7 heads from one of my 350's. Then again, I am not trying to get into the 10's lol

 

[olds307 and 403]

The FCR Alminum heads would work awesome with what you have but there is an ugly mess surrounding FCR right now. A set of 403 4A or #8 350 or any BBO head will work. Any early 330-350 Olds heads will put your compression sky high. The Edelbrock RPM heads are decent and a fuel pump block off plate and a performance electric pump and regulator can be bought for cheap. Go for the Edelbrocks.