As I mentioned, go look up the valve angles, etc. You'll be a little enlightened.
You need to speak to a builder who is well-versed in LS engines before you spout off "EGR abilities". The intake/exhaust flow is so horrible on some of the LS cylinder heads that the intake/exhaust ratio was well under 70%.....very poor, even by Ford FE standards.
Not sure how comparing a full race head to a street head is apples to apples, but if you want to go that direction, I would be inclined to say that the GM race cars didn't pull the heads right off the parts counter at the local dealer. Of course the camshaft selection would be different because the heads are not stock!
I'm not talking about how they rated them in the 60's. I'm talking about how they rate them now, and 1.2 hp/ci is actually pretty pathetic. Any professional builder here could take a 378 inch SBF and make 460 hp in a streetable form. Not to mention that naturally aspirated 5.0L Fords make 435 hp.....explain to me what's so nice about an LS?????
But if you want to make a comparison on how things were in the 60's, then remind me how many times Chevy won Lemans.....
