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Ok. So I thought I'd get back about the hybrid idea. Doing some quick math (not as quick as before) I found that the van at full GVWR of 6,100lbs takes almost 1,000kW/s to accelerate or decelerate, not including air drag and rolling resistance and such. But to go from 30 mph it takes a quarter of that, almost 250kW/s. A 10gal accumulator that goes from 1250psi to 2,500 psi stores about 240kW/s of energy. As far as the 80hp 48gpm motor/pump goes I calculated it actually can't put out more than about 70hp theoretically meaning it probably takes about 80hp to turn as a pump and gives out about 60 HP when used a motor, which is actually right in line with the average 75% efficiency of such a system (much better than the 25% to 30% of an electric hybrid.) Since most of my driving is below 35mph one accumulator will do. But the question is the motor. I'd get a little less than 3mph per second (which is what I do anyway) but only if I gear it to go 30mph at max RPM. So I either need to have a way to disconnect it or two pumps geared to 60mph.
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