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Don't get too wrapped up in static compression ratio. From 8.0:1 to 9.0:1 is worth a 4% gain. From 9.0:1 to 10.0:1 is worth a 4% gain. From 10.0:1 to 11.0:1 is worth a 4% gain. So, from 9.7:1 to 10.5:1 is worth about a 3% gain, or about 640 times 0.03 or about 20 horsepower. However, that little bit of extra power might come at the expense of a more radical cam to keep up with the cylinder pressure and prevent detonation. That bigger cam may have moved the effective cam operating range out of the comfort range that he had planned for you and the motor may have been less effective at what the main plan was. It could very well have made the car slower, depending on cam operating range.

Bottom line, ask him, but that would be my take on it. You fellows don't always have to run the range all the way up against the wall. That's one of my pet peeves with fuel pressure in carburetors. Why in heaven's name do you want to run the fuel pressure right up against the wall when you know that there's no advantage, only downside?

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