2 questions

[Waterloo]

So true what Rawze stated, these motors like that 1700+ rpm range. Been able to really drive the truck since rebuilding the motor. Been nearly two years of little to no work with this truck, been through multiple carriers, etc, just terrible.

Anyhow, I have been going West, running I-80, and had a chance to really break her in and play around with my pedal skills vs fuel mileage. I played around with 1400 to 1500 rpm, run a tank full, fuel up, etc.

Running that 1400-1500, she was a slug, just did not feel right. I did not last long, mileage was right around 5.8-6.0 in a fairly wind free trek across Nebraska. Yes, wind free, that's a first! Calm as I have ever experienced it going across there, very rare.

Then did the same running her at 1700+ rpm in a lower gear. I found 1700 rpm, which put me at roughly 65-67 mph in low 8 (18 Spd, 3:42 gears) seemed to be the sweet spot. In High 7 I found the same results with a tad bit better fuel mileage. That had me running at 59 to 61 mph and getting closer to that 7 mpg, 6.7-6.8'sh range.

This is a mid roof ProStar, CM-871 pulling a dry van. Wind has a huge effect on my fuel economy, along with ambient temps and of course the winter blend. I found my average fuel economy in the 5 mpg range heading West, and 6 mpg heading East, this is on I-80, Reno to Detroit, round trips on paper with the Tri-Pac.

That Tri-Pac sucks quite a bit of fuel vs my old one this new Evolution replaced. I did idle the truck a few times when the temps were hovering at zero and below.

If I put an air dam on the top, I think 7+ would easily be obtainable. A flat bed, I know I can get close to 9, which I have hit in the past with a blown head.

These numbers are on paper, fuel in the morning and fuel in the evening, taking the Tri-Pac out of the equation and then an overall everything accounted for trip average. I did use cruise in the flats, like Nebraska, my foot is old, needs a break now and then. LOL!

Overall, running at that 1700+ appears to be where the motor is happiest, and has really loosened her up, she feels like she is breathing now, the power (torque) feels stronger and she is very snappy on the pedal. She moves, and pulls like a freight train with little effort just feathering the throttle and keeping the boost low once the correct gear is found.

Honestly, this is one of the strongest motors I have ever driven, much stronger than those old Cat 550's or older Detroit or Cummins 500 hp motors I have driven or owned. Very happy, very sad I am parking her.