I had heard and read many different things regarding this fuel-box for the 6.7. Some say not to turn it up past 40% or you will damage your injectors. Some say it doesn't matter. I purchased it to increase my un-loaded mileage, and do not race or beat on my truck. (I have about 20k miles on it with a 6spd man.)

I spoke a TS rep and he said the best mileage gains will be if you turn the adjuster all the way up. He stated that on all the company trucks they just run a jumper and it stays on 100%. No problems whatsoever. I asked him about towing and he said the only time you would want to turn it down is if you have a heavy load(12k or>) and you were in a hilly area. He also stated that even though it may be turned up 100% there is not max fuel pressure increase ALL the time. (algorithm program or something)

Anyone else have any eperience or suggestions? I do not want to damage my truck or the injectors. Thanks in advance, Scott

 

Im in the same boat you are...except with my 5.9. I am really wanting to add the sixgun to my truck, but it adds quite abit of pressure I am told. Although I don't believe that when you are just cruising either box will add pressure over stock, but I don't know. I can't find anyone that has run a pressure gauge on a truck with a sixgun. I am also concerned about my injectors.

 

I have the ez in mine which is a presure box. Going down the road at a steady speed on level ground, changing the setting will change the r/p about 1200-1500 psi per level. This appears to increase with trottle, so I would say probably yes you might could possibly still do some damage even with light throttle. I only run mine on the lowest setting and can still hit over 25k on r/p under throttle.

 

i run mine at about 40-50% any more than that and the throttle is way too sensitive. At the track i run 100% with added pressure from my smarty. i havent had any problems. even when i was on stock injectors i would run it at 100% before i heard of people cracking thiers and never had a problem, but i said to myself, better safe than sorry.