can anyone tell me how to make a homemade compression tester

 

The most "accurate" homemade compression tester would have to be your hand... just hold it over the spark plug hole and see if you feel air when you turn the engine over.

If I were you I would buy a real one. only about 19 bucks for a real cheapo

 

were can i buy a compression tester cause i thought u couldnt use a normal one

 

Any good parts store. Just unscrew the schrader valve out of the end of the hose. It will work great.

 

http://twistedrotors.com/

He makes a rotary-specific compression tester, even did a group-buy on the rx8club forum a while back and I got one. Worth its weight in gold imho, it's the only definitive way to know the health of an engine. You can tell almost instantly if you've got a bad side seal, bad apex seal, overall low compression or an engine that's good-to-go. I don't know how I managed for so long without one. It's one of those tools (like a timing light or a good fuel pressure gauge) that gives you insight into something that you didn't have a way to know before and removes all the guesswork, letting you move on with your troubleshooting.

Jon