Quote:
Originally Posted by ksa8907
So at a 30:1 compression ratio (assuming temperature of the compressed gas stays at 60f which ot won't), the spring will need to be able to resist (425 psi x (piston area)in2) roughly 4500lbs depending on piston size and the effective dynamic compression ratio.
Is that math right? Seems high.
If that is accurate, you're certainly not using a mechanical spring.
I re-ran some numbers using 17.3:1 compression of a cummins 6.7 and 15 psig of boost, roughly 2700 lbs of force.
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Thanks, this is what I was looking for. Some math that says it's possible or not. I can't say if it is correct or not as I don't know how to calculate it.
What bothers me is that a small starter motor is able to turn the engine against the compression and start it. Maybe it's the gearing that makes it possible.
Maybe there is someone that can point us to the correct formulas, etc. to calculate it.
Thanks