[HDHeis]

Can anyone tell me if I can run cast iron heads on a filled BBC dry block (no coolant system) without filling the heads? I have a 496" BBC with a BDS 8-71 blower / alcohol injected in my dragster. I suffered some damage to my GM solid aluminum heads and want to use a cast iron set from one of my other engines. Any info will help.

Thanks, HDHeis

[jbvcw71]

Running full filled blocks is tricky buisness but it's not as sentitive as the heads as they're exposed to much more surface area.

The aluminum is a poor metal to run without coolant due to it's high thermal conductivity (absorbs & expells heat quickly).

Cast iron is a better bet but I'd have them filled & have them thermal barrier coated especially in the exhaust ports & chamber.

I have never seen finned heads for anything other than a flathead (valves in block) configuration. That being said, that would be the best way to go.

Fully finned aluminum heads with copper alloy ports & chambers.

They probably don't make such an animal so I'd go with the full filled cast iron heads. You may want to have the water jackets copper plated before filling so that if cracks occur, they wont be an issue as the copper is pliable & wont fracture as easily.

CNC machined Stainless Steel heads might be a good alternative to cast metals in a non-coolant application as Steel is PLIABLE & less likely to fracture due to uneven temp changes.

GOOD LUCK!

[Stroke]

CNC machined Stainless Steel heads

Whoa, never thought of that. How much is in the budget????

[HDHeis]

Thanks for the opinions. As for budget...it's gone for the season, that's why I just want to use my Merlin cast heads for the last few races. This winter will be the buildup of a bulletproof race engine.

[LilSmoke]

Go ahead and use the cast heads. Not an issue.Running alc as you know their isnt a heat issue other than trying to get it warm enough.lol How many lbs boost? Head flow close? You will prob have to juggle port nozzles a little for the diffs if used or at the very least,hat nozzles and main.Actually the cast iron will help to keep heat in the chamber,so keep an I out on the plugs along with leak and idle temps.Id suspect that the barrel will have to be increased a flat or 2 and or idle check.Square or k valve? -9 or -10 spark plugs? clutch or converter?