Smarty ???'s

[Jcummins]

I love my smarty stack setup on my '01.
I let my brother drive the truck and he asked if he could put it on his '99 and try it.
He has an old Edge comp. Not a drag comp.
The low end power and throttle response felt great as the smarty always helps.
But when we took the truck out on the highway and cranked it up to 75 mph, he set the cruise control and the truck suddenly started surgeing like crazy.
It felt like he was flooring it and letting off over and over agian.
We turned the comp box off and it stopped.
Any ideas?????

 

[Bob Wagner]

do you have an aftermarket lift pump installed on your brothers truck?

 

[BCSCUMMINS]

Mine did the same thing on my mom’s truck when I loaded it on there. But it did not have to be at 75mph it would surge at any speed with the cruise on.

 

[Jcummins]

Hey, Bob.
Yeh, he's got a Fass 150, you should know John I. doesn't let anyone out of his shop without one. ha ha

 

[The Turd]

had the same experience with the smarty on the street it is caused by how sensitive the throtle position becomes with the smarty loaded

 

[Jcummins]

So it's not the comp screwing up?
Never did anything like this on my truck, but I know every truck is different.
Bob get back in here!!!

 

[jktcummins]

Mine did the same thing. I am pritty sure it just has to do with the fact that the smarty has a very touchy throttle response that when it says to fuel the computer cant stop it fast enough to quit accelerating and when it does stop accelerating the computer shows its speed is lower than what is set so it fuels hard again to achieve the set speed and over fueling and then backing off again. If you download it to the lower numbers or just set smarty at 4 or even 2 then the edge on a lower setting it will not do this. But if you have the smarty and edge on higher settings it will surge.

The smarty fuels hard on bottom end it just fights itself with the cruise on. If you know what i mean???

 

[Jcummins]

Know what you mean, today I made a 310 mile round trip to see family and set the smarty on fuel saver and comp box on level 3 and all the surge issues went away. I agree that it is just the fact that the smarty fuels so hard that it fights itself, talked to several others who agree.
Thanks for everyones help.