A quick question. I've read that Iron heads will produce 30+ more H.P. for a given engine configuration. If aluminum heads cost more and produce less HP, what is their advantage?

Surely the difference in weight doesn't make up for the lost 30 HP does it?

 

You definately need to specify what on earth your talking about

Are you talking LT1 Imp heads versus aluminum LT1 heads? Imp heads are lower compression, but flow a LITTLE bit more, not alot. Aluminum heads allow for more timing, but bleed off more heat, heat = power inside the engine so its a minor tradeoff.

I'd save the weight, if your shooting for 5000+ HP I would guess that they dont use aluminum, or else its very thick/exotic alloys, who knows. For a street car go aluminum unless its a cost issue.

 

Hp vs. head material isn't simple. Fe heads are less conductive, so more heat stays in the combustion space which tends to make more hp. Al heads conduct more heat away, which is bad, but run cooler. By running cooler they are less prone to detonation and thus allow more timing, which makes hp. Al heads are lighter. Overall, Al is the best choice. Al heads with a ceramic heat rejecting coating are the "best of both worlds", but this adds a couple of hundred bucks and Al heads are already more expensive.

Couple of other advantages to Al heads: easier to repair if cracked, easier to port.

Rich Krause

 

I'd go AL heads aswell, less prone to detonation allows for more compression which in fact allows more power