I feel the 16 to 22 :1 compression ratios (P in the formula)is the diesel's greatest forte.

- now are we speaking of four cycle engines or two cycle types? All the loop talk reminds me of two stroke engine talk where you have no exhaust or intake valves just ports or slots in the cylinder bores to allow intake charge from the somewhat pressurized crankcase and exhaust passage from the upper cylinder area after firing. I think this is what a two stroke detroit diesel does or is.



I can see atmosphere pressure in the crankcase , I am at a loss as to why there is 5 psi (should that be 5" of mercury vacumm?) in the intake. How can you have 5 PSI in the intake manifold and still be naturally aspirated (non-blown) on a four stroke gasoline engine?

Its over my head--duck here it comes again!

Last edited by edski; 04/12/11 04:06 PM.