I read all these posts on how fast all your dmax's are.. I'm starting to wonder if mine is slow.. It really doesn't move too fast unless I put the pedal to the floor, which I don't like to do. It seems like the last inch or so of the pedal gets firmer and when I'm pushing down in that firm part of the pedal (WOT or just about) that's when the truck feels like it's moving.. But nothing really spectactular.

Do you guys.. with no power addons.. have to go WOT to get the truck to really move?

I'm thinking about going to the dealer on Saturday and take a LLY out for a ride just to compare.. I have a LB7, do they feel the same?

Thanks..

No, they don't feel the same. the LLY, IMO, seems to have a quicker jump to it. As for your 03, if you modify the muffler, the turbo will spool up quicker eliminating the turbo lag. It will move quicker and I am sure you will love it.

As for the LLY, still some turbo lag, but need to lose the kitty. I am working on losing mine, tomorrow morning. I will stay stock the rest of the way to see if i get codes or see how it performs. the kitty restricts it a little too much.

The other thing, to get things moving quicker, look into getting a predator, or bullydog or some type of enhancement. It could better your fuel mileage, according to how you say you are driving. If you ever want to move, just touch the accelerator and you will definately feel it. You don't need max out the programmers at all. I run mine on the 65hp, predator.

First thing is to get rid of the turbo lag, by going with a freer flowing exhaust. Aeroturbine makes a nice one that will sound almost stock and is 3.5 inches in diameter at inlet and outlet, similar to stock.

03DuraHDMax,

Put the pedal to the floor and hang on, it's the only way to drive. You will not hurt a thing.:grd: You may have to be careful towing heavy loads that you don't over rev, but that's it, hammer down. These diesel engines can totally handle it, especially stock. My friend had a truck that his dad drove, he would baby it all the time. When my friend finally took the truck from his dad and drove it the way it should, pedal to the floor, the engine came back to live. It took a good 6 months, but the truck has way more power now.
The lly is different, I agree with ncmic.

Another thing is to be warmed up.

I kinda feel the same way as you tho, truck dont seam to be getting down the road, but coming form a gasser may be why I feel this way.

The other night <ya ya I know leave me alone> I was at a stop light on a 4 lane road next to some kid with a honda and one of those coffie can muflers.

I just knew he was gona hit it, abought 1/4 mile down the road merges to a 2 lane hwy, speed limit 55. So when it hit green I got going. Note I didnt say I hit it, but I got going and just keept the truck at 2800rpms, bought the time I bothered to look I was doing 80 and nothing the guy could do was helping him catch me, I could see his head lights bob as he shifted hard trying to catch up.

I hit my turn signal, merged over as the lane with from 2 to 1 and then let off and slowd down to 55 mph.

I was pleasantly suprised, my truck is bone stock.

:cool2:

If I power brake, it will smoke the tires. But otherwise it really doesn't spin the tires. My truck seems to go fast, but not like the people here talk. The mods really must make a difference.

jeff
2002 duramax cc 4x4

remember the internet adds 100 hp and about 20 mph...

I don't know guys, my 04 lb7 runs real strong right from idle. Have since put on Banks 4" exhaust, power is the same just sounds better and I know egts are down.

for less than $1000, you can add the edge juice w/ attitude and a 4" exhaust. that was the best money i have spent so far...but already wanting more!

I'm glad to hear that it's not my truck.
I haven't really thought about performance mods yet..
First on my list is a Nicktane, autostart and XM. I didn't really know that there was all the power just waiting to be unleashed...

Well... now I'm thinking about performance mods!:rolleyes:

Winter blend fuel doen't help in the power department, thats for sure. I think my truck on winter blend has about the same power as an 8.1, but come summer time it's all Dmax.

Once mine is warm it get's moving pretty quick without WOT . I'm sure it's not like these non-stock rockets, but it's no dawg! It's not fast out of the hole at all though. Second gear on and it will scoot!

You might look at a post I made back in September about "doggy diesel". Since then I only have a few more miles on it but I have been in Lake Havasu this winter and really notice a difference. I think the altitude really hurts the performance before the turbo spools up. BTW, towing my fifth wheel 13K over the mountains here was a piece of cake.
Dave

Whats stock:confused:

Gotta remember the turbo lag......it will make it feel kinda unresponsive and thus slow. While I had my truck in the shop I had a nice loaner GMC gasser. 1/2 ton 5.3 ext cab leather ect., anwho......I gave it about 1/4 throttle and I'm thinking to myself "this thing is pretty peppy" give it a bit more pedal and I'm like......"ok, weres the power???":confused:

Things to remember.....it takes awhile to break in a deisel. Probably 10k, you will probably be able to notice milage increases too. If your past 10k. Also, the duramax is set up to lock the converter at WOT in second gear. Truck will pull much harder with the converter locked. Try driving around in TH, it will probably feel more peppy. Also the whole it takes some time to build some boost. You wont be able to break the back tires lose from a dead stop just mashing it. I've got double the torque you do or close to it and I cant, I start to move and then the turbo spools up and then its bye bye tires.

Come to the dark side:muahaha: You know you want a chip;)

also remeber your driving a 4x4 truck that weighs close to 7k#'s

Stock lly has all the performance I care to have. If I get some perverted need for acceleration and stuff then the Mercedes comes out of the garage. Truck is for hauling or towing, that's about it.

Transitioning from a gas engine to this turbo-diesel was an education. The gasser has a much greater response to small throttle changes than does the diesel. This makes the diesel "seem" like its a milk-toast vehicle.

With the turbo lag, it takes an extra second for the engine to start making power. The nice thing is that it makes huge ammounts of power when you tell it to - i.e. WOT.

On a related note - the throttle is purely electronic. There is no mechanical connection to a throttle plate on the engine (no throttle plate on a diesel, in fact!). The foot pedal has an electonic sensor that feeds information to the computer, and the computer then controls how much fuel is delivered by the injectors.
Any added resistance you feel in that last portion of pedal movement is artificially introduced and has nothing to do with the engine not wanting to make power.

Adding a chip will makea noticable difference when you hit the throttle hard. The turbo lag is still there. After that lag it makes lots more power.

Duramax's run consistantly with the 5.3/6.0/8.1 trucks, approx 16.4@86 1/4 performance. You may think that your truck is slower than these three engines by comparison, but the diesel is effortless in acceleration-seat of the pants won't seem as fast.

I think that the resistance felt on mine at near WOT was the carpet. I don't have ready access to a TECH II, so I've never been sure if I've been getting WOT or not. As some others have done, I put a few washers under the lower mounting stud for the throttle pedal. Then I trimmed the carpet right under the pedal brace. Now it goes in further without the resistance. It still doesn't completely bottom out on the mount, but it is probably now wide open, depending on how the volume knob is factory indexed on the pedal.

Steve

My diesel is for towing. If I wanted something for speed, I would of purchased a Vette!!!

Interesting...
I have to check to see if the pedal is hitting the carpet.

If you do decide the need for speed, wait for the new Z06 this fall. 500hp, 3150lbs and a Viper GTS beating 11.7 1/4 mile.

:offtopic:

I second the Vette. Another incredible GM product. Ranked number one all-around sports car this month by Road & Track.
I know a little off subject but it shows the incredible engineering at GM to compete with Porsche Carrera and
Boxter. Especially for the price.

Right after buying the dmax, I purchase an Edge Juice. I can honestly say that it is the only "car" that has pulled my cheeks (on my face) back on acceleration. Took it off for various reasons.

I have swiss cheesed the air box, and put on a Banks 4 inch exhaust.

Had a stealers diesel mechanic accused me of having a "black box" on it because it was so snappy.

Totally stock except for the air box and exhaust.

Plenty fast for me.

If you do decide the need for speed, wait for the new Z06 this fall. 500hp, 3150lbs and a Viper GTS beating 11.7 1/4 mile.I have no need to make my dmax any faster.. I just wanted to be sure it was performing as well as everyone else's stock. It's an 03 and I just bought it used. I don't really have a baseline to compare it against. I did drive home from work yesterday with a little heavier foot then normal and I have to say, I'm impressed.

As far as speed goes.. I have my 2002 WS6 Trans Am. This is the vehicle that get mods! LS1 http://dieselplace.com/forum/images/smilies/rockon.gif

3150lbs of torque for the Z06?! http://dieselplace.com/forum/images/smilies/eek.gif

"Do you guys.. with no power addons.. have to go WOT to get the truck to really move? "

A diesel, like a gasser requires fuel to make it go. Unfortunately, a diesel is much less responsive to the pedal than a gasser.

What the "boxes" do is insure that fuel is provided much faster and at a higher rate than with a stock engine.

That is why you don't feel anything until the pedal is almost to the floor, which is where it has to be in order to get more fuel to the motor.

A simple improvement like swiss cheesing the air box will make a small improvement.

Have a good time with the truck.

the 03 is less responsive than 02 qnd 04. i was at Gm training and an Enginer was saying that the program is a tad different causing the voltage at the pedal to range slower from 0-100%. fix is easy a little hokey but have seen it work...my 03 is the same and i just need a few hrs of free time to try the fix.

What is this secret '03 fix? Anyone else able to verify? What does the "hokey" fix involve?

03duraHDmax , I felt the same way about my dad's 2003 Duramax. It really felt sluggish and slow a while back and I was wondering the exact same thing as you. But I did a 0-60 run (when he wasn't around;) ) and with a 1500 rpm boost-builder, got a respectable 10.3 seconds. After that I stopped worrying about it as this number matches the average I hear around here. I know that under 1900 rpm accelerating from a stop, there is nothing there so if I need more gusto, I just put the pedal in a little further thats all. Come to think of it, my 6.5 diesel will toast our Duramax if the rpm were limited to under 2000 from a stop, but after that, the duramax takes it. Hope to make that even better with an Edge this spring:grd:

Comming from a 4.6 v8 gasser, I think my dmax pulls HARD. I was able to try out a Van Aaken once.... What a rush! Obviously I bought it right then and there.

Interesting...
I have to check to see if the pedal is hitting the carpet.

If mine ever hit the carpet it has long worn a hole in it by now. I'm at least 50% of the time on the floor. :D:D
A guy that rides with me a lot looked at the front of my truck once to see if my foot wasn't sticking out thru the radiator. ):h):h

I ran a 7.4 0-60 (according to the Juice/Attitude) the other day. I was on level 3 with low boost on 5. Pretty impressive, although it could have been a lot better... but considering all the snow that's melting around here it's a pain in the rear trying to get the tires to stick on wet pavement.

Dan

0-60 in 6.65 seconds on level 4.

3150lbs of torque for the Z06?! http://dieselplace.com/forum/images/smilies/eek.gif
I think that he meant vehicle weight.

I think that he meant vehicle weight.I see pounds I automatically think torque http://www.dieselplace.com/forum/images/smilies/redface.gif

I think mine pulls almost as hard part throttle as it does WOT. :ro) I know it pulls harder then my 01 6 ltr when towing. I love the way this truck pulls! Oh yeah, thats what I bought it for. My son tells me he got beat by a short bed extended cab Ford with the 6ltr PS :eek: Oh well the short light truck beat my crew cab dually with my 19 year old son driving... :mad: Censored Censored Censored He soes not get to drive it too often anymore..........