Camshafts and Compression

Valman said

Thanks RRR, I’ll check it out. We get talked into high compression by the ‘gurus’ sometimes I reckon. You don’t really need it.
I spoke with a few ppl when putting it together, in AUS & U.S. One a local Pro-Stock builder. The general consensus was you have 10.7:1, great quench, run it. In reality, it’s probably a bit high.

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It's certainly true. The forum gurus and all the magazine articles have you believe your junk won't even fire off unless it's at least a flat 10:1 and it couldn't be further from the truth. The ONLY reason my slant 6 turned out with 10.6 is because the head fell off the broach on one end and I had to get that milled out on a Rottler. The chambers went from 59cc to 34cc. I had to utilize the head, because all the others I had needed seats and guides and that one did not and I couldn't afford that. So I chose a camshaft with a 71 degree IVCE. Now THEN I looked at the valve events, because I needed to in order to run on pump gas. Otherwise, I would have had the "obligatory" .100" milled off the head and been "around" 9:1. I think it ended up close to .180" milled off to get it back straight and clean. It was a lot.