CR From Hell
Never Satisfied
- Joined
- Oct 31, 2007
- Messages
- 1,031
I've been hunting an "around town" fuel mileage issue on my truck for about a month now, and believe I narrowed it down to the Smarty. I run a 6.7 short block with a 5.9 head and electronics. 50hp Exergys and stroker pump. S467.7/87/.90
With the Smarty on SW 4, 5, & 6(Revo tuning) the overhead console would read anywhere from 12-13.2 mpg around town. I would reset it and it would go back to those readings fairly quickly. (Hand calculating showed 13-14 mpg) So I took the Smarty off and with stock tuning the overhead would read 15-16 mpg, and to be honest I couldn't tell much if any power loss, drove and spooled very well.
I thought maybe there was something wrong in that particular program so I updated the Smarty to TNT and tried again. With the following settings the overhead still read low around 13.9-14.4 and the truck was sluggish down low.
SW5
Speedo: 250
Shift Limiter: Stock
High RPM: On
Timing: #2
Rail Pressure: Default
Wastegate: Off
The second tune I tried yielded better results, 14.3-16.0, felt much better through the powerband, and was much more responsive.
SW6
Speedo: 250
Shift Limiter: Stock
High RPM: On
Timing: #2
Rail Pressure: Default
Wastegate: Off
My question is, to a certain point, shouldn't having the Smarty on produce better MPG numbers than with stock tuning considering my set up? It's not apples to apples but I ran Smarty in my last truck, granted it had 100% overs and a 475/87, but that truck never dipped below 17 mpg. Feel like I'm missing something very obvious so please enlighten me.
With the Smarty on SW 4, 5, & 6(Revo tuning) the overhead console would read anywhere from 12-13.2 mpg around town. I would reset it and it would go back to those readings fairly quickly. (Hand calculating showed 13-14 mpg) So I took the Smarty off and with stock tuning the overhead would read 15-16 mpg, and to be honest I couldn't tell much if any power loss, drove and spooled very well.
I thought maybe there was something wrong in that particular program so I updated the Smarty to TNT and tried again. With the following settings the overhead still read low around 13.9-14.4 and the truck was sluggish down low.
SW5
Speedo: 250
Shift Limiter: Stock
High RPM: On
Timing: #2
Rail Pressure: Default
Wastegate: Off
The second tune I tried yielded better results, 14.3-16.0, felt much better through the powerband, and was much more responsive.
SW6
Speedo: 250
Shift Limiter: Stock
High RPM: On
Timing: #2
Rail Pressure: Default
Wastegate: Off
My question is, to a certain point, shouldn't having the Smarty on produce better MPG numbers than with stock tuning considering my set up? It's not apples to apples but I ran Smarty in my last truck, granted it had 100% overs and a 475/87, but that truck never dipped below 17 mpg. Feel like I'm missing something very obvious so please enlighten me.
