I have 11:1 (up from 10:1) on my Griffith. It's a compromise really, if I could switch to E85 full time I would go for 12:1 or maybe even 12.5:1
As for cam, I went for the wildest road cam on the market, but that's just me...
If it were my experiment, I'd start at a 5 to 10% increase in compression and see what happened. Remember that it's easy to increase the compression, but as yet there isn't a "putting-back-on machine" for decreasing it again...
On my engine I'd expect more gains than most because the ports and valves are really too small for making big power from petrol, but it all seems to work out better for ethanol. (One of the snags of a 40 year old design of engine
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