Aluminum heads $ per HP?

Aluminum dissipates heat and all things being equal will produce less hp than the iron

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One of the magazines did a pretty good test of this on a SBC where they used two sets of the same model Dart heads.
One set aluminum, one set iron.
They made the same power.
I don’t know that there is any other platform besides a SBC where there are truely equivalent heads available in iron and aluminum.

Whatever difference there might be between equivalent heads that are iron or aluminum....... is minimal enough to where it shouldn’t be part of the decision making process for which to buy.

However...... that Chevy test was done with two equal heads.
Stock LA heads are not the equivalent head to something like an RPM head.
As much bad press as the genuine LA RPM gets, it would still require a set of pretty decent reworked stock heads to be as good.
So, on a combo as described above, unless the stock heads were done to where they were more reworked than just a little blending under the valve....... I’d expect the unmodified RPM’s to make more power.

When the BB RPM heads were pretty new there were all kinds of tests in magazines between them vs ported iron heads........ with the RPM’s usually beating the ported iron by 20-50hp.
The variables being how high an effort the motor was(hp per ci)and how good the ported iron heads really were.

My feeling is that if you’re “trying to make some power”, in other words not building an 8:1 318/360 for your DD, the only place the stock iron LA heads might be better than new aftermarket aluminum heads is....... cost.
And that’s a “maybe”.

I’m not saying reworked iron can’t be made to work well(as it has for many years)..... but depending on what the goals are....... an aftermarket aluminum head is likely a more cost effective option for many performance oriented builds these days.

To me........ for a new build it’s a no brainer.
If you’re “upgrading”........ then you’re back to “it depends”.