What have you guys done to increase the throttle response on the lly dmax diesels? I currently have an 05 with the edge/attitude and 4inch mbrp and I am about ready to send it down the road! I came from and lb7 which had all the power a guy needed from start to finish, same components only I hate the bottom end on this lly!

The Predator is way better on the take off then the Edge. I've had both and the Edge really does nothing at all for the take off. You do know the LLY is drive by wire, right. And it reduces the power to protect itself.
Dan

like DWRAT says "they are cut back in first gear." for protection stock or not

My LLY is a lot faster off the line than my buddies LB7. We both were running juice/attitude combo's. We haven't drag raced them yet, but he and I agree mine is much faster off the line. Did you have the 285's on your LB7?

Ya, both trucks had 285's and there is no comparison, the lb7 would light up the tires thru 3 gears and this lly just wont get out of its own way. I am sure it runs ok, probably better than alot of trucks but I miss my lb7 and just cant understand why they up the horsepower and torque and then cut you off at the knee caps and limit how much power is put out in first gear! The only problem I ever had with my lb7 was the tranny holding 5th gear and that got corrected with a little $

Is the Cat still there?

I removed my cat and it helped alittle but it is still alittle dead on bottom

I am in the same boat...you need a good 2 seconds at least till it fires up...I'd like a good solution myself.....lost about this one.....I suspect it is an electronic issue..these new trucks are "fly by wire"....When you push the gas pedal, you are really moving an electronic sensor......aren't you proud...You only think you are in control...LOL....the computer will decide for you...including the gear shifts...Even your brakes aren't really under your total control....

Mike

if you use the Edge/*** you can increase the Low Boost fueling from the default level 1 to as high as 5..that helps a lot for low rpm acceleration. keep in mind.. more power = less mileage ;-)

Forgive my ignorance, but when you say low boost fueling, do you mean the injectors let in more fuel even tho the turbo is at low boost? The reason I ask is that I already have too much black smoke...I thought that means not enough air to go with the fuel? Is that okay in a diesel? I admit I don't know much....


Mike

I think the LB7 is drive by wire too, no? I know all GMT-800 series gassers have been drive by wire since 2003. Anyone with an LB7 look for the RPO "KUP" in your glove box..."KUP" denotes ETC (electronic throttle control).

---Ben

dmax500hp

Have you killed the CAT and blocked off the EGR? That seemed to help my truck out.

88Magnum you are correct in your assumptions about low boost means low air, and putting more fuel in there will create a lot more black smoke, but it doesn't hurt diesels to do that. You just aren't getting a complete burn since you are starving for air. Until your boost comes up your just going to have crappy effeciency, so it is compensated with more fueling.

by the way this is the first DMAX i'ved owned and it now will light up the tires going into 2nd with 35's on it. I'd considered that pretty decent considering the size of those tires.

thanks Kappa


Mike

Yeah, my 05 has a nasty lag too. When pulling out into traffic from a dead stop I'm constantly misjudging how much time I need. My 5.3 Z71 would have no problems here.

I thought the whole idea of a variable vane turbo was to fight lag? I hear the lb7's don't have this problem. Guess it's time to try a Predator.

RideRed, I AM running the predator on the 85HP setting...still lags...actually didn't notice much if any change from stock..

They're all drive by wire. Try not to stab the throttle and just roll into it.Much better that way. Check your charge air cooler for leaks. Tim

I dont have a block off plate for egr, or fingerstick. To my understanding which may be wrong, is that the only reason you need it is in case you are setting your check engine light and I havent had that problem. Does the fingerstick and block off plate help performance @ all? I have done some reading but like I said it sounds to me like I dont need it?

I dont have the fingerstick but I do have a blocker plate and on my truck at least is seems to make more boost at slower speeds. this seemed to help the turbo lag.

From what I've been reading, the latest Predator firmware load for our LLY's will have the ability to disable EGR diagnostics...So, if that turns out to be the case, maybe the predator will improve the lag if it allows us to disable the EGR..Also, if it kicks the vanes in on the turbo at lower rpm's, this would do more than anything to improve throttle respons..At least that would seem to make sense in my mind...

Mike

I dont have a block off plate for egr, or fingerstick. To my understanding which may be wrong, is that the only reason you need it is in case you are setting your check engine light and I havent had that problem. Does the fingerstick and block off plate help performance @ all? I have done some reading but like I said it sounds to me like I dont need it?



I pulled a LLY apart for twins with 14k miles and the whole cold air side was full of oil and soot. One port in the plastic intake tube is used for vacuum to suck the oil vapor off of the crank case vent. It fills the cold air side with oil. The intake horn was full of sludge/soot from the egr. I'd say plug all that stuff off.

OK , we plug all that stuff off, so what would be the best way to clean all that soot and oil out of the CAC and intake?

do a search there was a whole step by step on cleaning your CAC, and how often as well.

i have done the EGR blocker and finger stick and it seems to boost faster. which makes it feel like more power but it is really not.

Just hack into gm's software and change the desired boost map, and the vnt position map to closed, and you'll be fine.

im not afraid to hack the software if someone can give me an decrypted version:) But then I guess thats half the battle... If it was a microsoft program I would have had it done by now, but then someone else would have already taken over my truck...