Thanks everyone for your replies. I just left the garage and the last little bit of
oil was draining from the
oil pan. The
oil pan had nearly 2 gallons of
antifreeze mixture in it before the oil started to come out. Tomorrow I will try to pull the plugs if I have time. I have a busy week ahead so I don't have much free time. I am still trying to decide whether I want to tackle this or not. the last times I pulled apart any engines they were a flathead V8 and a Chevy straight six with poured bearings. I guess I am dating myself.
Back to the questions asked: the compression ratio is 10:1. It has side pipes with no crossover. The last rebuild was less than 10k miles by Keith Craft. It has run great until now. I do get on it now and then, use it but try not to abuse it. I have not had it above 6K rpm. I did have heating issues at the beginning but they have been pretty good lately.