I'd go aluminum in a heartbeat, theres no reason not to, plus you rid 50 lbs off the front of the car and you can run about .5 more compression.
Hack said:I would probably buy aluminum heads over iron heads for a performance application, but I felt that someone should bring up the negatives of aluminum heads.
-the spark plug threads (and other fittings) can strip out and corrode much more easily.
-aluminum is not as stiff as cast iron, so it may not seal as well in blown applications.
- aluminum and iron have different rates of expansion, so heads may not seal to block as well.
-the higher rate of heat conduction in aluminum has some negative effects on power, but that can be compensated for by increasing compression.
rbohm said:as noted there are negatives to aluminum heads, but they can be overcome;
1: helicoil inserts can be installed to prevent aluminum threads from being damaged..
jerry S said:or just make sure to install your spark plugs and bolts with plenty of anti-seizing compound the first time around.
Edbert said:I've seen a number of guys paint their alooominum heads and intakes blue. Part of it for the stealth look, part of it to just be different. But yeah, I don't see any argument for using iron heads unless it is budgetary.
jerry S said:why is retaining heat anything to be desired? I thought one of the benefits of alum is that they don't retain heat.
65notch said:also...painted them will help retain some of the heat. black being the best color.
after doing all this work to the aluminum heads to make them able to keep more heat in, warpage problems, threads stripping, ceramic coatings, etc... the cost of them would be alot more than a good set of iron heads.
i dont need any fancy aluminum looking heads(infact i would paint them) so the look of cast iron works just fine. it allows for better combustion efficency, cheaper, less warpage problems and im not like everyone else with aluminum heads.
65notch said:and im not like everyone else with aluminum heads.