I knew my ears were burning for some reason. :DWe know you're in good hands with Tim. I've spent my fair share of time porting and flowing with some good guidance and the last set of SR that I did refinish, I don't know what they flowed but they made pretty good power all considered. I'm still behind the theory that flow is one part of what makes power and there are a couple more parts. I don't have #'s on my -1 stuff and I didn't 'do' them. I'll probably have the same guy go thru the 572-13 heads I have for next year and I'm not sure if I'll have him throw them on a bench...and I'm not sure he'd be willing! I think all the same the -13's can be better by another 50hp. Not that the bench isn't a good tool! I'd be curious to see a dyno test with heads done by Larry Smith when he was prime. He knew his way around these dinosaurs too.