Re: 8.1 Engine Mods
 

Yes, Adger, you can just send the ECM. People do every day.
If you have the Allison transmission, the gains won't be as impressive. The Allison has so much Torque Management programmed in it's computer (TCM) to protect it, that thing calculates the torque output, and tells the ECM to pull the timing back to protect the transmission. I had one truck with that transmission, and hated it. The 4 speed 4L80E trucks are much faster, use less fuel, and tow trailers better. Performance gains with the Allison are not nearly as noticeable. On my chassis dyno, the Allison trucks gained very little. I towed with a gasoline motor home a few years ago, with an 8.1L & 4L80E, it towed my trailer easily, and never an issue.

Re: 8.1 Engine Mods
 

Yes, Ed mine has the Allison 1000 Trans.
I read an article about "Limp Mode" in the transmission if you modify the engine and the two computers don't communicate.

Re: 8.1 Engine Mods
 

Ed, do you have a tune setup for a 7.4 chev in a 2000 1 ton dually auto. The fuel mileage when towing is brutal. Your always looking for gas station.

Re: 8.1 Engine Mods
 

My 96 Crew cab 7.4 auto towing a 10K trailer gets 8 - 9 MPG at 65 MPH
Is that the range you get?

Re: 8.1 Engine Mods
 

We sold our motorhome, if I get to race again I will be back to towing with my '99 7.4L Suburban. If I don't run much over 65, it gets 8 to 10, depending on hills & head winds.
Oklahoma has a 75 MPh speed limit on it's turnpikes (lots of toll roads in this crap hole state) mileage falls off a cliff @ 75/80. My 454" tows easier on much less fuel at 60/65.

Re: 8.1 Engine Mods
 

My truck gets 6 to 8mpg on a good day towing @ 60mph

Re: 8.1 Engine Mods
 

ED could you PM your address and turn around time. Thanks Tom