Well I am thinking that the bad compression might be because of my high altitude (5000 feet above sea level). That make the compression ratio go from 9.2:1 to 8.2:1 according to the calculator here:
Honda D-Series Compression Calculator by ZealAutowerks
Now I am thinking of increasing my compression ratio to help out with better mileage. It might cost more to do, but I really want to find the problem, and have it running like new.
How much can be milled off the head so it is still safe? A guy in a forum says .040 is fine. I just dont want my valves to ever touch the piston, I have had a timing belt brake while operating but thanks to hondas great engines no valves were bent since they cant reach the piston. In a chevy I had 4 of them bent.
Anyways, I am thinking milling maybe .040 off the head since it is cheap to do so, and change the head gasket for a d16y8 gasket. Doing this should get about 10.5:1 and at this altitude it should act as 95.:1.
I do this for experience and as a fun project, and cost is not so bad about 30usd to send the head to be milled and flattened.
Lets say I do this, and do a compression check to be sure of compression, Is there a way to calculate gas octane that should be used with compression psi?
Any thoughts or opinions on this project?