BlueCamaroZ28

Which is better flowing head.

Read that the iron head has 5% better flow.

http://www.automotiverebuilder.com/ar/ar99928.htm

carlos64030

The iron heads do flow better, but the additional weight will far out-weigh any flow advantages it may have over the aluminum castings.

ibanez6rg

You can get more out of the iron heads.

arnie

Might you have links to info that will substantiate that response?

Pasky

I think this is a matter of personal preference. I've seen many a argument about this, iron or aluminum. It seems you get better flow with iron heads but more weight reduction with the aluminum. Its the ketchup or mustard battle. IMO, go with the aluminum.

arnie

The original ? refers to flow, and flow alone. While it is agreed (?), that in regards to oem virgin castings, the iron has the flow advantage. However, to be fair, I believe the answer/discussion should also include flow with the full potential of the head realized, IOW, ported.

To uncomplicate the issue, leave the weight or durability variable out of the discussion. This way, the answer would not be a matter of personal preference. Now for the links giving the flow advantage to iron. Or was the above reply referring strictly to oem virgin casting flow #s?

BlueCamaroZ28

How about the combustion chamber size? What is the spec for each. Heard that the iron is 64cc ,while Aluminum is 58cc, yielding less compression.

96 WS6

Umm people, aluminum heads are the ones that are sought after. They disperse heat way better than iron.

LameRandomName

And need more compression to make the same power because of that.

arnie

That is a negative, not a positive. Heat is energy. If it goes in the radiator, it is not turning the tires.

arnie

Which is better flowing head?

It would be great, if we could stick to the topic/question. Iron does have larger C C, precise specs not handy, but the relevancy here, as I perceive it, is not the size as it relates to CR, but the flow influence (unshrouding) any additional area available, surrounding the valves generates, plus any flow influence/difference, in general, the different combustion chamber shape causes. Although an all around different shaped chamber could be considered an intangible, cuz it may have little affect on measured flow bench #s, but influence flame travel, which could have an effect on dyno #s.

Jeff H

The iron LT1 heads flow better than the aluminum F-body LT1 heads straight out of the box. The iron heads are the same as the Corvette aluminum LT1 heads, but the F-body aluminum LT1 heads are different(you know, the Corvette can't be slower than the Camaro). As for which head is better, the iron will hold the heat better which will make more power at the top end. Both heads can be ported to flow the same so that is a moot point. It comes down to preference if you want to save weight, go with the aluminum.

94SLUG

Iron normaly flow better, and have a stronger cast. Iron works well on boosted cars but they can develope hot spots. Alum lifts. I really think it boils down to the combo and goals you have.

Fastbird93

I beg to differ. The Corvette heads were the same as the F-body heads. The difference comes in the cam profile, but that's another topic.

The Iron Heads will flow better than the aluminum straight out of the box.

meengreen 94z

Ive always wondered why the ironheaded LT1 makes less power. Im guessing the cam profile is designed for more low end torque to get B-body cars off the line. or maybe a more restricted exhaust?

Impala SS's usually dyno 210-225rwhp
Auto LT1 f-bodys usually dyno in the 230-240rwhp range.