A question on Les Andrews's ring specs

[Marco Tahtaras]

Originally Posted by 700rpm

5/21/15 Update: With now 1875 miles on the new engine, it still locks up when it gets driven up to operating temps. I pulled the head and dropped the pan. There is no scoring or scuffing or discoloration on the cylinder walls. I conclude from this that my original ring gaps were too tight, and am going to regap them. There is minor carbon buildup on about 2/3s of each piston on the valve side, and a carbon ring at the top of each cylinder. I would like to hear from you experts what you think a better gap might be, and also your opinions on the carbon buildup.

Thank you.

What exactly do you mean by "it locks up"? Does it seize? Does the starter not turn it over? How about the hand crank (with OR without spark plugs)?

It sure doesn't sound like rings.