Got around to a compression test on my 22re the other day and found out I have pretty high compression. Cylinder 1- 200, Cylinder 2- 190, Cylinder 3- 200, Cylinder 4-197. I've been told before high compression is caused by carbon deposits stuck inside the combustion chamber/on valves and whatnot. Thought these motors should be around 140-180. It's been a real dog lately so I'm going to start running 91 in her now that I know how high it is. Has 215k on it. Is seafoam the best option to attempt to clean it out without tearing it all down?

 

Unless it's pinging this "high compression" is not likely your cause since it's really only 10-15 pounds higher than spec. I like to run some Marvel Mystery Oil in my gas personally to help clear carbon deposits, or some GM Top Engine Clean used the way they outline. Never been a fan of SeaFoam myself, I can get kerosene cheaper without the fancy can.

 

Are you sure your gauge is accurate?