What's your final gear ratio?
That Cummins can live with a staggeringly low (numerically) ratio.
My 7.3 Powerstroke thrives of (3.08 x 0.8 =) 2.45:1 plus the ZF6-550's overdrive gear.
Low gear ratios are very potent for diesels.
__________________
2000 Ford F-350 SC 4x2 6 Speed Manual
4" Slam
3.08:1 gears and Gear Vendor Overdrive
Rubber Conveyor Belt Air Dam
|