Is 120 psi good compression on outboard?
For a general number scale for compression. Two-stroke engines should be somewhere between 100-120 PSI per cylinder. Then four-strokes are going to be somewhere between 150-210 PSI! You will see a good compression reading of 150-160 PSI.
How much compression should a 350 engine have?
The standard Chevy 290-horsepower 350 Chevy crate engine you can buy isn’t even that good. Chevy’s literature states this is an 8:1 compression engine, and that’s what we found when we measured one of these engines a couple of years ago.
What should the PSI be on a four stroke compression test?
Good results for Four-Strokes should be 180-210 PSI, and Two-Strokes should be around 110-130 PSI. Here is everything that you need to know about outboard compression tests. How to do them and what the results mean for you! What Is A Compression Test?
What’s the best cylinder compression for an outboard?
However, four cycle engine cylinder compression should still be within 10% cylinder-to-cylinder. Older two cycle outboards, especially low horsepower, can run fine around 60 psi however above 90 psi is optimal. Four stroke/cycle engines produce much higher compression. The main thing to check is the difference between cylinder compression.
What’s the most compression you can get in a car?
On the other end of the spectrum, ~200psi is about the most compression pressure you will see in a non-racing gasoline engine. Where “normal” is for any particular engine depends on the compression ratio, which varies widely from one engine design to the next.
What should the compression be at idle on a ram?
ANALYSIS: Running compression at idle should be 50-75 psi (about half cranking compression). Snap throttle compression should be about 80% of cranking compression. runners. (Toyota, Vortec etc. with variable runner length) Comparing measurements between cylinders is important. cylinder-such as worn exhaust cam lobe, or collapsed lifter.