ok here it is I want alot of power down low, along with a better launch, basiclly want to change the low end on the 4.8 b/c the thing is slow off the line. want a combo of both more power, and a better launch.

 

what is your goal? off idle torque or a hard hitting launch?

if it is lower rpm torque the biggest obsticle to overcome for the grunt down low will be the lack of cubic inches with the 4.8. not taking anything away from the previous posters, as they are all sharp and know what they are talking about, but to build power low you will have to compensate for the lack of cubic inches in some manner such as your nitrous or a FI setup. monster off idle torque on a 4.8 without the help of a power adder of somesort isn't really gonna happen.

for a good launch you need something to get these heavy *** trucks a rollin. along with the usual upgrades such as exhaust, tune, cam, etc...gears is must to improve the torque leverage along with an efficient properly sized stall to get the rpm up to a few hundred rpm below max torque at launch.

 

ok cool ty for all the help, i got it now

 

The stall alone took me from bogging off the line to smokin when I felt like it. I think a stall 450.00
custom tune 157.50
shift kit 87.00
servos 12.00
this pakage took my truck from 2.4 60 ft to 1.9 60ft .Think about it 1/2 a second off the first 60 ft of a race.
P.S. You will need a tire upgrade and posi if your one legged.