Engine Health Check

Running 15+ PSI boost puts stress on an engine. It's a good idea to regularly check for developing problems, rather than wait for catastrophic damage. A leak down test will find burned valves, broken rings, and of course holed pistons and blown head gaskets. Don't confuse the leak down test with a simple compression test. You need a leak down tester kit and source of compressed air. The kit has adapters to fit the spark plug hole, and you set the air pressure regulator at about 100 PSI. The cylinder to be tested must be at TDC of the compression stroke. When you send the air into the cylinder, the resulting pressure reading will indicate the relative health of your engine. A poor reading will be accompanied by the sound of air escaping from the problem area. The photo below shows excellent health. You do not have to remove the valve cover to do this test... I just happened to be in the "neighborhood".

Walt....

Been doing that with 2 stroke sled engines for ever. You do a leak down to see if the lip seals are good in the crankcase. We only crank up 15 to 20 psi though and most engine manufacturers have a specified leak down rate for acceptability.