Right way to launch auto??

[Ranch96]

I have read some info about this but want to know for sure what is the right way to build boost and launch w/ and auto tranny. Just hold the brake hard?:burnout

[stump0331]

eh dont know about 4wd on the floor but for 4wd on dash guys its:
4 high
brake to floor
build about 15psi
let off break
go pedal to floor
after 2nd gear take out of 4 high

[Clay Henry]

Yes he can shift out of 4x4 high after second gear with the manual stick.

[Marty]

Rarely does it come out of 4x4 thought because of the driveline stress.

4HI, hold brakes so that is barely holds the truck back and when the time says GO -- release the brakes and mash the go pedal. I can hold BOTH to the floor in 4HI and build alot of boost.

I wouldn't recommend doing this ALOT because it's HELL on the T/C...

[owtcast]

That just sounds like you're trying to grenade something in the powertrain.

I've seen some viscous couplers that advertised that they were made to relieve the stress between front and rear drive axles. They bolted up to the front of the transfer case in between the yoke and driveshaft and essentially made a AWD truck instead of a 4wd. (there is a difference) The target market for these were people that lived in snowy conditions so they wouldn't have to bother engaging and disengaging the front end everytime they hit a slick patch in the road. I bet they would work wonders for the launches ya'll are describing.

[Ranch96]

I'm not going to the track or anything and won't be doing it very often. Just trying to get my friend with his "my truck is faster than your truck" 02 stock 4wd Dodge dually cummins to race. I know I will woop him, I just want to do it real bad!

[owtcast]

Originally Posted by Ranch96

I'm not going to the track or anything and won't be doing it very often. Just trying to get my friend with his "my truck is faster than your truck" 02 stock 4wd Dodge dually cummins to race. I know I will woop him, I just want to do it real bad!

You're an evil man

[Marty]

Originally Posted by Ranch96

I'm not going to the track or anything and won't be doing it very often. Just trying to get my friend with his "my truck is faster than your truck" 02 stock 4wd Dodge dually cummins to race. I know I will woop him, I just want to do it real bad!

You won't even need to launch it...

if it was an 03 commonrail that may be a different story though.

At the track i pre stage, then when the other guy is staged and ready I go ahead and start building boost. When i get about 10 psi, i roll ahead and stage- then its game on. I leave the line at no more than 10 psi or i get some terrible wheel spin.

[EODguyJake]

When you guys launch in 4hi, do you have the hubs locked in, or are ya using the auto lock feature? Not to change the subject, but I don't really know what conditions that the auto feature on the hubs work under? I'm sure it is below a certain speed, and some other stuff like that?