predator/edge stack, bucking at 95mph

[kevincolliver]

when i set just the predator on the 125hp it runs up to well over 120 just fine, when i turn the edge on and up to level 4 with the predator it starts bucking at 95mph like the speed limitor is kicking in. any ideas.

its a 2002 gmc 2500hd ext. cab short bed allison truck

[fcduffy76]

Hey Kevin, it may be a different problem but I am seeing something similar with just the predator. When I set the cruise at about 72mph it starts to buck or surge until I slow below 70 or speed up past 80. It did it when I had a Westers Garage tune on the ecm also. It is like the throttle can't figure out if it needs to give it fuel or shut fuel off so it keeps kicking in and out. This is on my 04 lly if that makes any difference. Also when I have a tune on my truck the throttle is so touchy it is irritating. You can not take off easy it like stock. I kind of feel bad for pinning my kids to the back seat every time I take off. I'm not sure it it is the same but thought I would let you know.

[Kennedy]

I would suggest checking fuel supply restriction and consider adding fuel lift supply from something like my twin pumps. This should eliminate the potential for supply issues provided you have a fresh fuel filter.

I am assuming you have your transmission upgraded?

[Jim Brzozowski]

If he don't he soon will. Merry Christmas JK

[kevincolliver]

the tranny is planned in the near future, it is handling it pretty good so far, i dont rod on it everyday tho so hopefully it will make it thru the winter. i am trying to get the local track here to start some sort of a diesel class here next year, right now the fastest thing around that i know of is bts (brians truck shop), his twin turbo'd powerstroke is running high 12's, i guess that is something to shoot for smile.gif

[DmaxMaverick]

"Rod"ing it isn't the "quick killer". It's when you are cruising, and roll into the pedal. Torque rises, and will overcome the T/C, then the OD clutch. The limp tolerance for the T/C clutch is much more generous than the C-# clutches. Keeping out of OD will help save the clutches, but will still slip the TC if it's locked when power comes up. Towing with power will expedite the process.

Back off the stacking and higher power levels, or you'll be shopping for a tranny before you're ready....Just friendly advice.

About the stacking....
There is a specific order of programming/plugging to get the best performance w/o stumbles. It varies slightly between truck models. The reason is, both power adders are doing essentially the same thing (timing, pulse width, fuel volume), and can conflict. It may take some practice, but can be repeated once you get it. Check with others doing the same thing, with the same year and config. truck. IIRC, high speed bucking was one of the conflict results.