Plus I think we are back to summer blend of diesel and mileage usually goes up with that too so my whole test may be a sham.......

 

i hear the new smarty S 67 is going to add a few mpg for those looking for gains in that area, and as a bonus, you will not need to powerbrake it from a stop to get er to smoke the rear tires!

 

Every time someone mentions the S67 Smarty, Chuck Norris clubs a baby seal...

 

not defenseless baby seals

 

FWIW, I just put mine in (5/10/08) - preparing for a summer of travel-trailering. Right now I've got about 7% bio in the tank and I haven't noticed any 'extra' rattle - the butt dyno wants to say it's a little snappier off idle.
I've kept track of my mileage (nice charts on gasbuddy.com) since I bought the truck so I should be able to notice something after a few thousand miles. I'll certainly report back when I have some conclusive evidence.

 

I still have no gains to report....

 

Must be a typo, gotta be 'navy seals'.

MikeyB

 

Yeah we don't want to pi** ace ventura off...

 

In my view, a "box" is a better solution. It can advance timing consistant with keeping EGT's under control. The sensor takes control out of your hands and you don't really know if the engine is operating within safe parameters.

Just my .02. Oh, one downside is the "boxes are way more expensive.

 

Yes you are correct that a box is more expensive. I have vowed not to put a box on this truck though. I also just had the Rokktech laying in a box on my workbench so I had to try it. It only advances timing up to two degrees and if it were too far I would hear timing rattle. I don't get any of that so I am sure it is safe. I am even thinking about pulling it off and filing something down to see if I can get more timing out of it. It's been a couple weeks now and my mileage is exactly the same. I may try loosening the Tone ring bolts and making sure the tone ring is adjusted to the advance side too. There is a tiny bit of play on it's dowel pin and it is enough to hurt the mileage if it is to the retarded side.....
I can't belive none of you has gone out to see if you can easily powerbrake and turn the tires loose. Mine does it easily and I don't know if it's the Rokktech that is helping me do it......

 

I got the itch the other weekend to see if i could powerbrake I was on asphalt (dont know if that makes a difference from cement or not) and i wouldn't say it was easy but it did it. Once you get them spinnin you are golden. Smoked em pretty good, then let off the brake, spun for a bit and then caught. It was fun though!!

 

Boxes also void your warranty, so its safer to try out the Rokktech.

 

I would say that a box will void your warranty no more than a rokktech... I run my Smarty Jr on SW#1, thats timing only.. so is the rokktech.... And arguably the Smarty Jr will be harder to trace as there are no clean connections and screws underhood...

Also they don't technically void your warranty, they just give DC ammo to not pay your repair bill... they legally have to prove that your mod caused the problem, but their lawyers are better paid than your lawyers.

 

The Rokktech can be pulled off in minutes with absolutely no trace that it was ever there. The Smarty is supposed to be undetectable but I have read of a few guys who said the dealer dug deep enough into the ECM and found traces of a performance box and even a Smarty. I can't confirm or deny this. Anyways, I am sure that most of the performance boxes give better mileage but I just don't want to mess up my warranty on a 6.7 that has proven to be problematic for many people. The 08s seem much better and that's why I got one but I'm still gonna play it safe and stay box/downloader free. It is very hard though! I can tell you that....

 

I am not saying that the rokktech is traceable, but if they look and see a "clean" area on the motor its there word vs yours...

As far as the Smarty, I don't believe there is one confirmed case of it being traced... And with most smarty users being Internet savy we would know...

I like the idea of the rokktech, I may think about one if the smoke issue with the Jr doesn't get fixed, because I wont run another box.