The Effect of Dynoing in Different Gears

370Z Purist

Transmission gearing and "multipliers" are very complicated; the final gear has little to do mathematically with the rest of the gears. The final drive has more to do with the rotation after it's been through the transmission. If we're in 5th gear, the ratio is 1:1 in the motor/transmission connection... then if the final gear is 5 and the diff is 1, that means that for every one revolution of the engine, that's one revolution of the tranny gear, which is five revolutions of the final gear and the diff gear is 1, so that means the wheel turns a total of five times for every single turn of the engine.

Sorry, just building up my own logic there.

Of course, with the data you've given me, assuming that both the AT and MT cars have the same diff and diameter of tire, we can say that the AT car will produce less torque because it has a longer final drive, if RPM and gear (5th for 1:1).

TL;DR

AT has less torque when RPM, 5th gear, same diff and tires than an MT.

I'm probably wrong but at least we're thinking now.

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-Phil

"Since one of my brake light bulbs just went out, the forum told me that my piston rings are about to blow."