more power

[jdjim]

have 98 k1500 5.7. auto 3.42 gears (actually a gmc but thought i might get more response from the chevy forums). ran pickup on dyno other day, found power was as good as it should be, completely stock. i need more power. it was suggested to me to redo exhaust, put in aftermarket off road y pipe, without cats and dual exhaust then have computer programmed to ignore the o2 sensors since the cats would be gone. has anyone ever done this and how was the success? also suggested to swap in cooler heat range copper plugs instead of the platinum plugs. any other relativly cheap hp booster anybody know of? am thinking of swapping in 4.10 gears. does computer need to be programmed to shift properly or can i just leave it and have a speedo off? thanks in advance.

[MT-2500]

Originally Posted by jdjim

have 98 k1500 5.7. auto 3.42 gears (actually a gmc but thought i might get more response from the chevy forums). ran pickup on dyno other day, found power was as good as it should be, completely stock. i need more power. it was suggested to me to redo exhaust, put in aftermarket off road y pipe, without cats and dual exhaust then have computer programmed to ignore the o2 sensors since the cats would be gone. has anyone ever done this and how was the success? also suggested to swap in cooler heat range copper plugs instead of the platinum plugs. any other relativly cheap hp booster anybody know of? am thinking of swapping in 4.10 gears. does computer need to be programmed to shift properly or can i just leave it and have a speedo off? thanks in advance.

Why do or would you need more power?

Removing cats and adding VCM programers ar illegal operations.

Changing gear ratio you need to change both front and rear.

[jdjim]

towing camper up hill, would like a bit more power. i know i would have to regear front and rear but was wondering if i did does it need reprogramming for shifting purposes or just for speedometer readings. you can buy catless y pipes and most of the muffler shops i called said they can leave them out but would most likely get a check eng light all the time. this is why i like this forum, you can get opinions and input from others.

[jdmccright]

Taller gears would help, but technically doesn't increase power. Unless the camper is really heavy (more than 5,000 lbs) I'd say 4.10s would be overkill....3.73s would be more appropriate. Fuel economy will suffer a bit.

You can get a custom true dual exhaust with high flow cats, keeping the stock sensor configuration.

The Vortec intake and heads were a major improvement in 1996, so not much you could do short of porting and polishing them.

A higher-lift roller cam and lifter gear would be somewhat reasonable in cost.

A little more expensive would be an ECM reprogrammer or module.

Hope this is a good start for you...good luck!

[jdjim]

thanks so far. im not so concerned about mpg. use to pull camper 90 percent of the time. 3.73 would help but 4.10 would be alot easier on the rest of the drivetrain. if calculations are correct i would be around 3000 rpm at 65mph in direct. dont think that would be a problem. i always pull in direct. if im not towing it would be in overdrive. i know these are calculation numbers not real world numbers. if anyone has same set up let me know what rpms you run in what gear. i have 265/75/16 tires. how about calibrations after gear change. can i leave it without any harm? is it a dealer calibration? is there a "little black box" i can get to calibrate it? too bad they arnt like a 80s pickup. change the cheap plastic gear and go. thanks for allthe info.

[MT-2500]

Originally Posted by jdjim

thanks so far. im not so concerned about mpg. use to pull camper 90 percent of the time. 3.73 would help but 4.10 would be alot easier on the rest of the drivetrain. if calculations are correct i would be around 3000 rpm at 65mph in direct. dont think that would be a problem. i always pull in direct. if im not towing it would be in overdrive. i know these are calculation numbers not real world numbers. if anyone has same set up let me know what rpms you run in what gear. i have 265/75/16 tires. how about calibrations after gear change. can i leave it without any harm? is it a dealer calibration? is there a "little black box" i can get to calibrate it? too bad they arnt like a 80s pickup. change the cheap plastic gear and go. thanks for allthe info.

If you re gear it much you will need to change tire size setup in pcm/vcm.

Changing or tampering with emmisions is illegal but.

They do make a re programmer that you can/adjust tire size and gear ratio and transmission shifting in VCM computer.
Works real good on setting up gear ratio and tire size.
Good Luck