True enough. I guess if one if going to dump 60k into buying and supercharging a vehicle, 300 to 400 / month on gas should not be too big a concern LOL.

Although talked with my wife's Diesel owning Uncle tonight about his tow experience and he is claming 15 mpg. Hmmmmnnn - damn garage!

D

 

Yeah my cousin, who may also be a lier at times, claims his 03 duramax with big exhaust and bully dog, with 35" tires and 6" lift gets 17 MPG towing his 12000 lb, 36' fifth wheel through mountains and flat combo. He didn't ever check, apperently just drove it. Then one day my other cousin in his stock duramax was following him with a approx 7000lb trailer, couldn't keep up, got 11 MPG, and was pissed off. Allthough the second was alot newer and not broken in yet. They used the odometer from the stock truck and apparently that is what he tells me. Kinda pisses me off too. But my truck is cooler, so there...

 

Dyno tune is done, very impressive intake temps, 395 RWHP, 415RWTQ. 2 bar tuning seems to run very nice, some small issues but nothing Nolan can't fix right up. Fuel milage is averaging 9.0 MPG towing at 90 KM/H, 8.5 MPG at 100 KM/H, 7.5 at 110 km/h, and this is all in mountains and some short flat spots. Only bad thing is price of premium fuel. I have put on 550 km empty driving in mountains with only one tank of fuel and it was 16 MPG, speeds varied. So far impressed, not sure if dyno tune really helped milage, but the entire trucks driveability is far improved. That is exactly what I was told would happen. I will check back here after another 8 days of driving.

 

So far so good for me as well on my trip. Edmonton to Fairmont, a lot of hills, and getting 28.5L/100 km for the trip up to Fairmont, better than the 35L/100 km I got on the July long weekend pretune. All in all I am very happy with my tune as well, and am used to price of premium (even here in B.C. where it is $1.35/L and I have a 110 L tank or so - can you say $150 fillup?????)

Have a good trip Rocket - compare notes next week.


D

 

thanks for the great info and results guys. I will be tuning for SD with some help from a "freind" and HP tuners soon, keep the results coming. BTW, i was told you lose a LOT of resolution with a 3 bar map.

 

You will lose resolution with the 3 bar, but not with the 2 bar. 2 bar is excellent for up to 15 psi were as 3 bar is good for 30 psi.

No need for 3 bar unless you are running big boost.

 

cool to know! i do know that a 3 bar is waaaay over my head! BUt im looking forward to SD .

 

This is my fuel consumption tracking. Before SD tuning and after. Keep in mind that ground speed and terain affected it mostly. Overall I am satisfied, just not really impressed or anything with milage. Also consider it is Canadian gallons not american.
I am most happy with the tune in the under boost area and slight boost area's say to 2 psi. It really made good torque there and would pull the 9000lb load up most hills (except giant ones) in 3rd gear and just keep going. The odd time it would need full 5psi and on large hills would stay at a minimum 90 km/h. If it hit 80 I would let it get second gear and if I wanted to I could accelerate to 110 km/h in second, but RPM was high and fuel guage would literally move one line in a minute or so.
Nolan was able to get 4* timing at full boost, and a hole bunch at part throttle. I beleive that is helping me a bunch. My EGT's also seem 1000* lower on average. He was also supprised to see the 395 RWHP and 414 RWTQ on a 2500 HD with 4l80E and 14.5" rear diff. I was happy.
Then all hell broke loose when the temps hit 38*C. E-fans would not keep up at anything over 30*C so I had to buy used fan, hub and shrouds when I had my originals sitting at home in garage. Kind of a **** off. Then immediately I noticed a drop in torque up the hills. Now it only pulls average hills in third and anything larger it must be in second to do 90 km/h. I tried hard not to let it get second gear, but on some it was impossible. Obviously this was why the HP and TQ numbers were higher in Nolans mind. Now to try and find a beter solution than manual fan, but still move enough air. Any ideas?

 

I know this is an old thread but it is exactly what I am looking for. I have the radix on my 03 avalanche 5.3l and am scheduled to swith to a 2 bar system and dyno tune by swtuning. I want it for towing and mpg's. So what is your outcome? I will move and travel alot so is the map system not adviseable due to the changes in weather and elevation? This will be quite expensive for me ($900) so any input before I get it done would be appreciated. Thanks

 

Still running fine 2 years later. Still getting about same mileage towing (approx 7 to 8 mpg) and not towing (about 16 mpg) on highway.

Good luck! If you don't have a custom tune already I am sure you wil be happy with the result. Keep us posted!

SC