Okay, I've got a 2007 LBZ Duramax with about 110K miles on it. I'm running trans safe EFI live tunes and wanted to hit up the drag strip for the first time ever tomorrow. There's a guy with a cummins running his mouth so I gotta show him whats up. I ordered PPE toe rod sleeves and had them over nighted to me for this Friday (tomorrow). I installed the tie rod sleeves but when I went to lower my torsion bars the bolts snapped. I'm not sure how long the truck has been leveled because I bought it like this about a month ago. I was able to snap the bolts with a 3/8 ratchet and no breaker bar. Anyway, since I can't lower my torsion bars to launch. What should I he safe to launch at in 4wd? If at all? My CV shafts are on just a slight incline right now. Truck is sitting level. I launched 2 times at about 1200 rpms and kinda rolled into it and it didn't hop but it did feel a little weird. Heard my tires screetch a little and coils definitely tell the tires were towed in! Will probably be doing my launches in my 90HP tune then switching to my 150 after the launch! Any opinion is helpful! Thanks!
Need personal opinion on 4wd launch
- Thread starter LBZ_Baker98
- Start date
Well don't change tunes goin down the track. Negative angles result in smoothest launch. Dhd brace or cognito braces help with straighter launches as well. Also make sure your front end is tight, ball joints, tie rod ends, pitman and idler arm. If you don't have traction bars id get some clamps to clamp the front of the leaf spring pack to the overload. It will knock some of the movement out.
Changing tunes going down the track isn't a big deal IMO. 1200rpm isn't a very hard launch so if that gave you weird feelings something might be wore out in the front end. My truck is slightly leveled and CV angles are still straight, launch it around 12psi, has a dhd steering brace too. If your pitman and / or idler arm is worn that might give you grief.
Guess it's a little different goin from 800hp to 950hp with a twist of a switch vs trans safe tunes
I launched mine at 1850, but my converter is an 1800 stall, so I was leaving at 10 pounds of boost. Resulted in my dash board split down the middle, bent tie rod sleeve, and a twisted driveshaft. I strongly reccomend taking it easy until you know what yours can take, and not do like me and push it to hard, spin all 4 launching, and break a bunch of stuff.
I wouldn't run the truck until you can adjust the bars down. Loudmouth Cummins guy will just have to wait.
wouldn't changing tune after launch be unnecessary? just leave it in the higher tune and don't press the accelerator as much until you are moving good. or ease into it
smaller tune launching with more accelerator or big tune with less accelerator = same stress if done right
or am i missing something?
smaller tune launching with more accelerator or big tune with less accelerator = same stress if done right
or am i missing something?
With the truck still leveled, you are asking for trouble. I've been beating on my truck launching 10 PSI or so with stock height and sleeves, but I've just been lucky not to snap important parts.
From all the shenanigans, I'm currently paying the price. Replacing the ball joints, pitman arm, and idler currently, all of which were prematurely killed by 4x4 launches on a front end not really setup for it.
Sent from my FlashScan V2
From all the shenanigans, I'm currently paying the price. Replacing the ball joints, pitman arm, and idler currently, all of which were prematurely killed by 4x4 launches on a front end not really setup for it.
Sent from my FlashScan V2
Highlighted above, no such thing and read the disclaimer otherwise known as fine print on the tuners website...:spit:
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make sure your front end is off the ground next time you start adjusting your torsion bars
I was thinking that but didn't want it to be true.