Performance Traction Bar System

[More Power]

Performance Traction Bar System
http://www.thedieselpage.com/reviews/caltracs.htm
Product review: Big power can stress unmodified chassis and suspension components in ways that limit overall truck performance. Pushing

[Seattle Steve]

Great writeup! Do you have any feedback or results yet on how they work at the track and on the street? I would appreciate hearing about it. I am hoping to eliminate launch shudder (GM won't address it in my cab/box configuration) without sacrificing handling or ride. Elimination of wheel hop would be a bonus.

[More Power]

I'm in the middle of a rear disc brake conversion. Weather permitting, I'll do more testing this winter, and will report what develops. These are really slick traction bar setups that are NHRA approved, and should go a long way to improve times.

These bars should also help eliminate launch shudder in a street truck such as yours. You could also experiment with some angled spring perch wedges to drop the pinion one or more degrees. I suspect your pinion is climbing too high during a high load acceleration, which takes the rear u-joint outside a range of angles that produces a smooth running u-joint.

MP

[BMDMAX]

The Cal-Trac setup works great. I have been running mine for quite a while now on my daily driver. I got mine from John Kennedy as well.

They help get my truck into the low 12's and really control the axle wrap. They help on the street as well. I have no shudder or hop of any kind. I would highly recommend giving John a call about them. You can see them installed on my truck in this photo.
http://www.kennedydiesel.com/photogal/images/meyers.gif

[More Power]

Thanks BMDMAX,

I assume your truck is a 2WD. How would you describe your launch technique? Thanks...

MP

[Kennedy]

He launches like a little girl :D BUT you'd better watch out 'cause each time I got out ahead of him he ran me down... :(

[BMDMAX]

John, I launch like a little FAT girl. :D I think at Bryon I was giving up a little over a tenth to you on the 60' times. I was running 1.8's and you were getting 1.7's for the short times.

It does not sound like much but it is a huge jump out of the hole. Of course your extra weight and the 4WD drag caught up with as I cruised on by to the traps. ;)

MP,

Launching the 2WD takes a little practice but once you get used to it you can do it all by feel and sound from the engine. I can't spool more than 10 pounds of boost without breaking through the lights or having the truck crab sideways from the torque rise, even with the slicks. The 4WD guys can launch with a bit more boost.

I get the slicks warmed up and then get the pre-stage bulb lit. I will then start spooling boost slowly, usually to the 6 to 8 pound range. I then let the truck creep to light the full stage bulb. By this point if all goes well I am usually between 8 and 10 pound of boost for the launch. On a non-LED Sportsman's tree I will launch between the second and third yellow.

A quick shifting tranny really helps with the Cal-Trac's, you don't want to give them any opportunity to unload in the first 60' of the run. A bad 1/2 shift that takes a long time can easily do that. Depending on track conditions I am into the nitrous usually right after TC lockup.

With the Cal-Tracs and the 1500 spring packs I bet you will get pretty good weight transfer compared to mine. With a set of slicks I would venture that 1.7 60' times in 2WD are possible out of that truck.

Good luck at the track!

[duraace9sp]

question????

are the 4 whell drive guys running the quarter in 4 wheel drive????
...any drivetrain problems with this -- running full throttle past 100mph in 4 wheel drive???

thanks...

[ 01-12-2005, 06:54 PM: Message edited by: duraace9sp ]

[More Power]

duraace, Yes, it's 4WD all the way.... Up to 111-mph so far. Some suggest hitting the 2HI button partway down the track, but I doubt the system disengages due to the load on the drivetrain. Lil Red produces faster trap speeds in 2WD when using a 150 Juice/Att, but produces about .2 sec lower ET's in 4WD, at that power level.

I'm in the process of converting the new 14-bolt SF rear axle to 12" discs. The original 10" drums and stock front discs could not hold the 3-4 psi powerbrake staging. My first attempt when using the hi-output JK VanAaken blew through the brakes in spectacular fashion, redlighting/aborting that run. I don't hit the nitrous trigger till we're into 2nd gear. :D

BM, Thanks for the launch tips....

MP

[duraace9sp]

thanks for the reply!!!!

i have been worried about blowing the front apart....wasnt too worried about the 11-1/2 rear end....but also have issues with the G80 rear end--as it doesnt lock into posi (by design) unless u r almost stopped (GM states under 15 mph)----so if u stomp it at 30 its a one wheel wonder....

all info appreciated---hate bad experiments that blow/break/cost!!!

thanks!!!

[More Power]

With a G80 rear, you need to powerbrake in 2WD - just slowly turning the rear tires to get the diff to lock. Then select 4HI, and roll a ways to get the front to engage. Make sure the front is fully engaged before launching, or you could break stuff. I now make a couple of tight turns to check for front engagement. It hops a little on dry pavement, telling me the front axle is engaged.

As with any performance testing, you're on your own for a warranty.

MP

[duraace9sp]

LOL---thanks!!!
breakings gotta be easy with this over 1000 ft lb torque!!!
which begs the question-----do you or is there a value in running front traction bars????

[More Power]

Bars are only needed on the rear, due to the leaf spring windup. The Eaton E-Locker for the front diff seems to be a popular choice.

The guys at PPE who have raced a 1500 series 2-door Tahoe 4x4 at 900-1000 hp (gas) say that without a front locker, the front-end will swing right then left, then right then left during a launch as one front tire finds traction, then the other. With a locker, they say it'll always swing left due to the engine torque lifting the left front tire and planting the right. This all happens very quickly and can catch you off guard. I think the key is to find a recipe that produces a hard launch with min wheelspin.

JK has given me several other tips that I'll try in the spring in an effort to help the launch. I'm still on the steep portion of the learning curve.

If all goes according to plan, this truck will be at the next "Weekend on the Edge". Should be a good time! :D

MP

[ 01-12-2005, 07:48 AM: Message edited by: More Power ]

[duraace9sp]

PPE???

those are the guys that sell the ATS torque converters under their badge.......at least thats what i have heard....
...but actually havent heard any bad things about PPE either---as they apparantly do good with the Hi po diesel...
whats the best value and options for a front locker???
and what comes in the LT dmax 4x4???

thanks yet again!!!

[More Power]

The Eaton E-locker seems to be the most popular for the front differential. Most are staying with the factory G80 in the rear. I had the folks at Randy's Ring & Pinion (http://www.thedieselpage.com/reviews/randys.htm) install a new Eaton Positraction in Lil Red's rear diff last September.

As far as re-badging products... Many, many vendors do the same thing with a wide range of products. It's like tires. I heard once that there are only a small number of tire manufacturers, but I can't count the number of tire brands out there.

MP

[duraace9sp]

cool---thanks for the replies---ill look and see if i can find the elocker for the front around here (so cal)----which are preferred the electronic vs air vs load lockers??
reliability is #1
thanks

[Kennedy]

I offer the E-locker with new carrier bearings installed for ease of installation.

I did not use my E-locker too much at the track. I found with the bars cranked down I could launch plenty straight, but then again, I have a bit longer wheelbase than most...