aluminum heads

1wild&crazyguy said

Magnums aren't better, they do have a closed chamber and on some flow bench somewhere as stock flow 3 cfm more @.300 [1.94 vs 1.88, but at all other lifts flow less than an LA head. Then they also have pedestal stud mount rockers, thin castings that crack and don't have much potential ported form beyond 250 cfm, meanwhile LA heads hit 270-290's cfm on an average when ported, just bowl blended LA heads flow 240's on the intake.


Those who say they are better need to show me their flow #'s stock and ported.

The magnums beyond stock don't even get close the old heads.

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i think that the chamber diference makes alot more diference than alot of people realise since we dont race flowbenches anyway.
as for what the old LA heads flow,well ported 270 sure. 290 is probably out of reach for 90percent of the people who knows anything about how to redo a set of heads to actualy work and at that point they are anyway out of reach for 99% of the people who is paying for the work to be done and pretty darn thin and there is a risk of them craking over time anyway.
but i do agree fully about teh shaftmounted rockers being lots more stable,its almost scary to watch how much the GM design moves around when any kind of springpreasure is aplied.
btw my eddelbrock heads are ported by someone who knows a litle about how to make heads work and he has a flowbench and he was very disturbed about the flownumbers edelbrock said that the rpm heads where suposed to have stock they where far of from truth and he was not impressed with them in anyway exept for that the heads where atleast straight when they came out of the box..anyway they ended up flowing somewhere around 290cfm at the peak with a good average on the lower lifts and they are real thin in criticalareas like pushrod pinch and close to where the innerrow of headbolts are,i cant see how an older castironcasting could flow as good as these things does without risking of ruining the heads if you go to thin in these spots and with castiron its alot worse to repair if you go to far.