Quote Originally Posted by southerner
Well the heads that he has got on that 327 are going to work a lot better than those open chamber heads that he has got sitting on the workshop floor. And those closed chamber heads produced up to 30 ft lb's of torque right across the engines rev range. If closed chambers are bad howcome world products make closed chamber SR torkers with 68 cc chambers out of cast iron ? Also all the mid sixtys small blocks made some respectable horsepower with closed chamber heads. Then along came 1971, with open chamber heads to drop the compresion ratios to reduce NOX emissions.... "Bang" all the engines right across the board lost up to 30 - 35 HP.
How come World Products makes 76 cc heads,Pro Topline,AFR etc.
If money where no object and I had to use stock heads I would rather use a 441 or a 993 and "roll" them over.
Compression is over rated.
I would rather see an efficient head with an "open chamber" than an inefficeient head with a closed chamber.
You take about the mid sixty's.
In the early 70's what kind of cylinder heads did the Ls6 have on it?