Bigger Really IS Better
Ever since we bought our current MH I've always thought it wasn't geared right. At a 70 MPH cruising speed it was turning over 2,000 RPMs, which is a bit too high for an ISL engine. Cummins gearing ca...
Forum Discussion
Chris Bryant wrote:
Sounds like the chassis was set up for those tires originally.
I'd agree with that. I was surprised when I called Spartan on it, as mentioned, they said everything was right where it should be. I knew better. An ISL shouldn't be running over 2,000 RPMs at cruising speeds.
DSDP Don wrote:
Bruce....You have one last fix that will give you back that acceleration and will let you see 9mpg. Add the DIgiCR computer chip. You can buy it at Parleys Diesel or Brazells. It will add 52 HP and a 1/2mpg. It reverts back to stock at wide open throttle to protect your engine and trans and doesn't leave an imprint on your ECU.
I added one to my 2005 Diplomat with the ISL. I know others that use it as well. They're about $650.00 and only take a few minutes to install. Plug and play. It has multiple settings. Everyone with the 400 ISL set theirs at (9) with one exception. One coach didn't like (9) and was set at (8). It was a large heavy coach.
Hmmm...I've never been one to do much in the way of chipping anything I own. I'll have to do a little digging on this.
As to the slightly less performance off the line, believe me, it still has plenty. Before it was darn near a race car, well...as close to a race car as 30,000 # can be. :B
It was good enough I always said I'd give up some performance to gain some MPG. We gained the MPG, and other than the off the line stuff, gave up nothing.
