DODGE/DODGE RAM HORSEPOWER AND TORQUE CURVES
If you study these performance curves you will see two major benefits of GearSplitting. As an example we’ll use the A-727 or 518/618 trans chart with a 5.9 24 valve engine and a 4.10 rear axle. Gears are multipliers of torque so at 2,000 rpm in 2nd-over the torque multiplier is 4.64 where without the GEAR VENDORS you would get into 1560rpm in 3rd-direct at 4.10. The difference in engine torque is less than 10lb ft. but the difference in the multiplier is 4.64 vs 4.10. That’s over 13% more working torque.
At this same moment horsepower at 2,000rpm is 170 instead of 125 @ 1560 which is 36% more horsepower with all the reliability of your stock powerplant. To figure the drop in rpm or torque multiplier from one gear to the next calculate as follows: Final Drive Ratio of the gear you are shifting to, divided by the gear you are shifting from, minus 1, times 100. The difference from 1st-over to 2nd is even more dramatic. This is why if you are towing or loaded heavily, the best way to reliably improve performance is with the GEAR VENDORS UNDER/OVERDRIVEâ„¢. It’s the same reason the big 18 wheelers have 2 and 3 speed auxiliaries for 10 to 15 or more gears.
Click on graphs to enlarge.