Quote:
Originally Posted by NeilBlanchard
If the crankshaft rotation was counterclockwise - would the power stroke have better mechanical vectors?
The radius of the crank pin is much smaller, and based on that, the torque would seem to be MUCH lower for the left side diagram.
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Interesting thought. I see what you mean... this is basically the reverse of a stroker modification... instead, you're getting the engine to act like a short-stroke one with the same effective movement range. I don't know if it's noticeable, but the piston on the VC-T actually accelerates slower at the start of the downstroke than the standard piston, where all the power is supposed to be made... and contrawise, due to the eccentric movement of the upper link, if you reversed the motion, the VC-T piston would indeed move faster on the downstroke, which *should* give more torque. (...uhh... right?)
But I'm assuming Nissan makes it rotate that way due to side loading and efficiency. Plus, it will probably rev higher (if these other considerations outweigh the extra friction caused by the extra link assemblies) Besides... with a turbo, they can probably cover up any torque deficiency inherent in the design... they're claiming V6-like power... meaning 250-300+ hp... though that's not too terribly far out for a two-liter turbo nowadays.