2005 5.3 vs. 99-02 5.3

[KDL8614]

I had a 0-50 "race" with my 05 Z71 and got beat by a 99-02 model z71. I know those models had about 285HP and my model has 310HP. I would assume he has some sort of chip maybe or his axle ratio was higher, mine is 3.42, just wondering what the big difference was.

[carson84]

im pretty sure that your 05 has more torque management than the 99-02 model. and your right, the gear ratio has a lot to do with it. also a programmer or a programmed pcm could have been in use. i have an 06 5.3 and it's a dog off the line. it also has 3.42's. gotta love GM's way of trying to get better gas mileage.

[Sierra H/O]

The torque management and the 3.42's are definately what's killing you. I have the same set up. Have you noticed how strong your truck pulls from 35 and up. The L33 HO motor has a little different cam than the iron 5.3. It makes the 310 horse at around 54-5500 rpm. That's why eventually I'm going to 4.10 gears, and someday when it's lifted on 35's, I'll consider 4.88's vs. 4.56's

[Fast305]

im pretty sure that your 05 has more torque management than the 99-02 model. and your right, the gear ratio has a lot to do with it. also a programmer or a programmed pcm could have been in use. i have an 06 5.3 and it's a dog off the line. it also has 3.42's. gotta love GM's way of trying to get better gas mileage.

3.42s were the performance gears at one point in time. 2.73s/3.08 were the economy gears. Fact is though the 4.8/5.3 just lack low-end torque to get a good launch with anything less than 3.73 gears.

[KDL8614]

I have noticed the engine pulls hard at mid-range speeds and highway speeds. What does the torque-management system do?

[Ross 650]

Howdy,
I have an 04 Z-71 with the 3:70 gears. I have a FlowMaster Super 40, cold air intake, and a reprogrammed PCM from Wait4me. I am running 285X75X16 tires. I can spin my tires pretty easily from a dead stop on pavement. I ran a Hemi 2wd and he could beat me about 1/2 length in about 100 yds. At 30 mph, we would stomp on the gas and I could jump him about 3 lengths. I ran a Nissan Titan and from a dead stop we were about even. At 30 mph he could take me about 1/2 lengths. I agree, it is probably the torque management that is killing your low end. Have a goodun!!!!

[Sierra H/O]

I have noticed the engine pulls hard at mid-range speeds and highway speeds. What does the torque-management system do?
It cuts back ignition timing at low speed under heavy throttle to save on the transmission. Timing retard= less power. Less power under shift=longer trans life. It's kind of a bandaid on a bullet wound type thing. For most people, they wouldn't notice. For performance folk, its PITA. Get a good tune, I'm going with a Diablosport Predator. If you don't hammer it all the time, your trans will be fine.