ORIGINAL: canardlover

RVM - yes indeed tinkering is fun and sometimes helpful but I think Hobbsy has a good point regarding your .82. I doubt that CR=13.5 can be combined with 20% nitro without detonation so unless you have a very clear objective on what to achieve leave it alone.
Buy yourself a couple of dirt cheap worn out or crashed engines, take them all apart and try to assemble one functioning engine incorporating simple mods you can perform with a press drill, a Dremel and a grinder. Leave the lathe and the milling machine till later.
This is the way I do it and makes it all much more relaxed if there is a mishap. Also try to obtain the booklet (by Mr.Rice?) on Saito engine maintenance which is really helpful.
RVM I do NOT say this to discourage you from tinkering - just the opposite......but do not start out with a well functioning engine which you need for flying.
.....sack time again....Cheers/Harald