Hey, I am happy to share. Everyone has been wondering what could be done.
There is certainly some hours involved. None of it is that difficult but a methodic approach lile making a template is a good idea. And the first time one doesn't know how far to go in some areas so it's a bit of trial and error. I use an air grinder with a 3/4" carbide bit and roughing it out went pretty fast. I think there was several pounds of shavings on the floor though...haha Then I use mostly a 3/4" 150 grit sanding roll to finish. Took quite a few of those.
I was a little surprised when I cc'd the chambers and they were that big but there is plenty of surface and valve clearance to mill the heads down. I used a calibrated beaker and water and did it several times with all chambers so they are pretty consistent.
My ratio would be higher but the pistons are still .020 down in the holes. We did not want to deck the block this time as it was ready to assemble but will at the next rebuild. I think it will be closer to 12:1 then which I think will still be fine with pump gas but we'll have to be carefull with the mixture and timing, etc. You are right about more compession is good. I can't believe the added power just raising this much.
Thanks for the comments, we are all learning.
Cheers,
Gary