Towing with an Edge EZ

[Sarge]

After much consternation I finally caved in and added an Edge EZ to my rig, primarily to get a little extra power while towing. I also kept the fuel box summary in mind in the latest edition of the TDR. I am very conscious of the effect of a fueling box on my HPCR. Constant opening of the relief valve has caused significant issues with the rail, as reported by a member of the boards that is a diesel tech at a dealership.

So, I picked up an Edge EZ box from a member at a good price, and drove about 40 miles to meet and pick it up. I thought I would do a comparison of the Fuel Pressure, Exhaust Temps, and Boost both before and after adding the box. The 40 mile one way trip was almost all freeway, moderate but moving traffic. The cruise was set at 65MPH both ways. The terrain was slight inclines and declines. And just for the heck of it, I reset the MPG on the computer once I was on the road and rolling at 65. I checked the average mileage both ways at the end of the ride. All readings were taken off of my built in gauges. Also, my max boost I could get out of it before it would de-fuel was about #29. The results were interesting........

The trip out stock saw the following numbers: Fuel Pressure- #7.5 avg. Exhaust temps- 600* Boost #6-#7 avg on the flat. Computer MPG at the end of the first leg 16.9 MPG. (I have never averaged those numbers in real world stop and go driving with this truck).

Hooked up the Edge in minutes, and headed back. I started with the 3 position switch in the lowest position to start, reported to be an increase of 25HP/50 ft lbs torque. Impression: not a lot of difference. A little quicker acceleration, and the fuel gauge showed about #1/2 MORE fuel pressure. Other readings were not noticeably different. I decided that I would most likely run the box on position 2, so I switched to the middle power level, 45HP/77 ft lbs torque.

NOW I'm feeling it, and saw some interesting changes. The cruising fuel pressure is at least #8.5 lbs. The EGT's have DROPPED to 500*, and the Boost is now pushing the truck on the flat with only #4-#5 lbs! Hmmm, didn't expect that. Very responsive throttle now, and I noted the max boost under hard acceleration will hit #32 lbs. I haven't seen those boost numbers since I had the TSB done back in September.

Conclusions, and hopefully they will prove out: Apparently the truck is now being pushed along at the same relative speed, using LESS fuel. That would explain the higher fuel pressure, lower EGT's, and lower boost numbers required for the same speed. I hope to see some MPG benefit when I tow this weekend, am sure I will notice the extra power on the grades. I will post impressions when I get back.

This test was not very scientific, and I am no engineer. However, if you were on the fence like me about adding a box to help with towing, this looks promising. By the way, the computer MPG on the return trip was 20.7 MPG. That I am sure is a fantasy, as I know the EDGE wacks the computer somewhat. But considering this rig was getting 14.5 empty, and 8-9 mpg towing before, any little bit will be gratefully accepted

By the way, NO codes were set by adding the box. Sarge