Building to race rules is a whole different animal. You have to meet their rules regardless if that is the most efficient setup. Also, anecdotal evidence, i.e. someone told me, is not documented evidence. I gave you a link to some relevant and documented testing, that is what I am looking for in this regard. Now if you had a dyno run that showed 915 heads made more power than Stealth heads, ALL ELSE being the same, then that would be interesting.

Years ago one of the big name aftermarket head makers ran an add showing something like 50hp gain with their heads over stock heads. If you read the tiny fine print it said compared to stock 305 heads on a 350. LOL, well no chit cherlock as my Dad would have said. Wonder how it compared to stock 350 heads on a 350? [/quote] Here's a good example, A 69 Camaro 396/375 in Stock with auto which is the most popular, is rated at 412 HP with iron heads, the same car everything else equal with identical factory aluminum heads is rated at 405 HP. In NHRA Stock, it's common knowledge that 10K spent for a 3 hundredths gain is a good deal so with money being no object, they can't get the aluminum heads to equal the iron heads all other things being equal. The aluminum head car can run 56 lbs lighter but most guys pull the extra weight to run the iron heads. The same thing with the 62-67 383, 7 HP more for the iron heads and nobody is running the aluminums. That's an extra 80lbs for the 63 383 to pull in H/SA to run the iron heads. The combo's that show more HP for the aluminum heads on the Mopars are rarely built.