|
03-08-2018, 10:32 PM | #11 | |
Veteran Member
Join Date: Mar 2005
Location: Sand Springs, OK
Posts: 8,132
Likes: 896
Liked 389 Times in 168 Posts
|
Re: 8.1 Engine Mods
Quote:
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.
__________________
Ed Wright 4156 SS/JA |
|
03-09-2018, 06:21 AM | #12 |
VIP Member
Join Date: Dec 2001
Location: Texarkana Ark/TX
Posts: 2,399
Likes: 496
Liked 724 Times in 280 Posts
|
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.
__________________
Adger Smith (Former SS) |
03-09-2018, 10:20 PM | #13 |
Member
Join Date: Oct 2009
Location: Whitecourt,Alberta,Canada
Posts: 229
Likes: 4,147
Liked 47 Times in 25 Posts
|
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.
__________________
Bruce Cameron 68 Nova 396 E/S 68 Camaro SS/? ex Checkmate Modified |
03-11-2018, 09:23 AM | #14 |
Member
Join Date: Mar 2011
Posts: 186
Likes: 0
Liked 28 Times in 15 Posts
|
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? |
03-11-2018, 04:38 PM | #15 |
Veteran Member
Join Date: Mar 2005
Location: Sand Springs, OK
Posts: 8,132
Likes: 896
Liked 389 Times in 168 Posts
|
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.
__________________
Ed Wright 4156 SS/JA |
03-11-2018, 04:50 PM | #16 |
Member
Join Date: Oct 2009
Location: Whitecourt,Alberta,Canada
Posts: 229
Likes: 4,147
Liked 47 Times in 25 Posts
|
Re: 8.1 Engine Mods
My truck gets 6 to 8mpg on a good day towing @ 60mph
__________________
Bruce Cameron 68 Nova 396 E/S 68 Camaro SS/? ex Checkmate Modified |
03-11-2018, 07:03 PM | #17 |
Senior Member
Join Date: Aug 2003
Location: Pierce NE
Posts: 906
Likes: 56
Liked 305 Times in 107 Posts
|
Re: 8.1 Engine Mods
ED could you PM your address and turn around time. Thanks Tom
__________________
Tom Meyer 5240 SS Stock ??? |
|
|