parish8

iTrader: (6)

got my new tranny today but got to thinking maybe i should work on my launch a litte before i pull the old one since 1st is still good. got to use the new gtech also, it is prety cool.

the first thing i noticed with the gtech, i stall strait to 4250rpm, hold there for a little bit and then the rpm's rise. WOW!! that 3000rpm stall is stalling prety high. the gtech had at least 20 data points just for 1st gear and that is when i let off. atap only gives me about 12 for a whole 1/4 mile run.

1.82 60', that seems prety good to me, it is launching freeking hard.

bucking bronco, this thing is violent, i need to figure this out quickly, hopefully before i toss that new tranny in. i dont want to smoke it because of a harsh launch. i can give numbers here to help show how violent it is. the trusty new gtech will give you g's graphed over time, i was seeing 1.3+ g's then swing to .3 g's did that about 4times before it smoothed out. very harsh.

i plan on geting out tomorrow with a cam corder and taking some video of my launches. hopefully i can see where the problem is, if it is just wheel hop in the rear that is an easy fix(caltracs?) if it is the front wheels jumping around like i have seen some FWD cars than i dont know what to do. i did one launch in 2wd because i forgot to put it in 4wd and i didn't move, i mean i didn't move at all, bam-6000rpm and not moving.

any ideas, i hope the video will make the problem clear, i was hoping th eaton would smooth things out but it seems to be worse now.

BigTex

iTrader: (16)

Definitely want to see the video. Did you loosen the front torsion bars any? After I unloaded mine, I haven't had that bucking problem nearly as bad.

StupidFast

I see you got new injectors. What happened to the 42s? How do the 50s idle? Do you need a converter box to run them? For future use <img border="0" alt="[evil]" title="" src="graemlins/gr_devil.gif" />

parish8

iTrader: (6)

sold the 42's for close to what the 50's cost, it idles fine, havent really got to push the injectors yet with a bad tranny and all but it runs great. no converter box, i think you can go all the way to 55's without a box

1999stepside

Have you ever thought of just buying some slicks and trying some 2wd launches? Isn't there less parasetic loss from going from 4wd to 2wd? Either way, sounds like you will have a nice 12 second slip coming your way pretty soon.

Kent

parish8

iTrader: (6)

shot some video and it sucks, you cant see much. you can hear it some but cant really see it.

my torsion bars are in the stock location, the truck even looks a little low up front so i dont know if i want to drop it anymore. the only things i can think of to do are

caltracks or traction bars
diferent tires
diferent tire inflation(more or less?)
tortion bar adjustment

here is what i think is hapening, the truck grabs, the front end lifts puting less weight on the left front wheel, it looses traction causing the front suspension to violently unload and the rear to peal out, the front comes back down and grabs hard and it starts all over.

i am looking for ideas on how to reduce this problem, anyone got any?

Black Blown 02

I have helper springs in back for trailer towing and it doesnt buck at all on a 4wd launch. Less suspension movement and weight transfer is why, I think. BTW I have a TT 3000 and procharger.

Texas Terminator

LOVE my cal-trac's!!

parish8

iTrader: (6)

i would toss on some caltrac's in a minute if i was prety sure it would fix the problem but who knows, it might make it worse. i either need to try and get soo much traction in the back that if the front left wheel gets really light it still wont peel out

or... do something to prety much eliminate any weight transfer so that wheel keeps the weight on it and never gets a chance to slip. the problem with this route may be too much power going to the front diferential wich looks kind of weak to me.

BigTex

iTrader: (16)

Try this for a cheap test:

First, unload the front torsion bars a little. MAybe turn each bolt one full 360* turn. Thats easy to put back to stock if it doesnt work.

Second, buy some U bolts that are wide enough to fit around your rear leafs, and long enough to clamp the bottom short spring to the top spring. Make a "cap" for the U bolt out of a piece of flat bar stock with two holes drilled into it. Then clamp the rear springs to stop the extra play in them. As a test, clamp only the rears of the springs first, then the fronts, then bots sides.

This will stiffen up the rear ride, but it will assist in taking out the extra play in your rear that may be causing that bucking effect.