IQ52/Jim I didn't see this thread before, but love all the great information, also great #'s out of Pop's old 440, in all configurations, truly impressive, very well done, my friend... A wise experienced man that I know, that once told me, "3 thing you need to build a great engine to start with, #1 Cylinder heads #2 Cylinder heads #3 Cylinders heads"... thanks for all the posting & question answering, I know I love reading your porting specs, build & dyno results posts... you gotta' love how great heads make a world of difference... I'm liking the results of that 2" spacer too, better HP/TQ pretty much across the board... Thanks again for taking the time to educate the masses...