Traction Bars: Whats the Purpose of These?

Chevy1925

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I understand how it works, the key to leaf springs is allowing it to flex, but not to much. A caltrac is locked solid under acceleration but not before you lunch.
So can you use an axle wrap bar and improve traction by setting your preload right, I have had luck with it, this has been the street. Will a caltrac system do better, I will try to find out at the track. The a big benefit will be me losing over a hundred pounds due to the size of my bars.

a cal trac is not locked solid under launch, it is continually trying to put pressure or release on the spring by a certain amount depending on how much preload you put in it. its continually changing. and when your boosting up for a launch, your pinion is moving up, the cal trac bars are moving till the pinion quits moving. i dont know what your getting at here. your never going to out do a set of properly setup cal tracs at the track with a set of regular axle wrap bars.

why in the world are your bars over 100lbs??? are you using .250 DOM or something? mine when i sold them with bolts, brackets, u-bolt retaining plates, and bars weighed 66lbs shipped.

chromoly tubing has great properties that can be used to advantages ;) :D
 

c20elephant

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Apr 25, 2013
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These probably weigh a 100lbs.

24zf3iq.jpg
 

MAXX IT OUT

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Mar 1, 2013
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The cal trac bars are moving till the pinion quits moving.
Why in the world are your bars over 100lbs??? are you using .250 DOM or something? mine when i sold them with bolts, brackets, u-bolt retaining plates, and bars weighed 66lbs shipped.

chromoly tubing has great properties that can be used to advantages ;) :D
70in, and i would bet it was .250 DOM but i got them free. So your saying the the bar on the bracklet thats on spring hanger hits the spring, and pushes the spring down to allow more rise of the pinion. Sorry, I need to get this strait in my mind, I believed I understood how it work.
 

Chevy1925

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These probably weigh a 100lbs.

24zf3iq.jpg

dylans are just retarded lol

70in, and i would bet it was .250 DOM but i got them free. So your saying the the bar on the bracklet thats on spring hanger hits the spring, and pushes the spring down to allow more rise of the pinion. Sorry, I need to get this strait in my mind, I believed I understood how it work.

no but here, pics speak louder than words



as you can see, there is alot of gap between the spring and the cross bolt above the spring i have circled. the rear end is off the ground in the pic so once back on ground, the bolt will be much closer to the spring to where you can adjust how much pressure it then puts on the spring (or preload as ive been calling it).

so in the pic, as the pinion rises (up arrow), the axle will push the bar forward (arrow point to the right) which will then cause the cantilever to press down on the spring with pressure. caltracs use the rotating movement of the axle to help "give" and net you a better launch without locking up movement of the leaf springs/the axle in a certain direction.

lowered trucks can have an issue with the length of the bars being too long to back preload off on the springs. i built a set of bars for ruben a while back to replace the bars on his caltracs (direct replacment bars, not axle wrap bars. his bars were pretty screwed up from adjusting them so much). while i shortened them up and used better heims/tubing, they were still a tad too long for his rig but its hard to nail something like that when your not personally there to see what your working with.
 

MAXX IT OUT

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Mar 1, 2013
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dylans are just retarded lol



no but here, pics speak louder than words



as you can see, there is alot of gap between the spring and the cross bolt above the spring i have circled. the rear end is off the ground in the pic so once back on ground, the bolt will be much closer to the spring to where you can adjust how much pressure it then puts on the spring (or preload as ive been calling it).

so in the pic, as the pinion rises (up arrow), the axle will push the bar forward (arrow point to the right) which will then cause the cantilever to press down on the spring with pressure. caltracs use the rotating movement of the axle to help "give" and net you a better launch without locking up movement of the leaf springs/the axle in a certain direction.

lowered trucks can have an issue with the length of the bars being too long to back preload off on the springs. i built a set of bars for ruben a while back to replace the bars on his caltracs (direct replacment bars, not axle wrap bars. his bars were pretty screwed up from adjusting them so much). while i shortened them up and used better heims/tubing, they were still a tad too long for his rig but its hard to nail something like that when your not personally there to see what your working with.
I guess my last question was, when the cantilever bar on the downward arrow hits the spring, that is what I was calling full lock, or does it compress the spring more?
 

Chevy1925

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I guess my last question was, when the cantilever bar on the downward arrow hits the spring, that is what I was calling full lock, or does it compress the spring more?

its not done once its hits the spring, there is still movement and an increase in preload the harder that pinion tries to point up. While you cant sometimes physically see it, that little bit of give/movement can be the difference in your fastest 60ft time ever or spining tires.
 

Forever

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Jan 4, 2009
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Glad I found this thread, as I was just going to post a thread about the same thing.

I have a 2010 LMM with around 550rwhp. Leveled with 305's & 20s.

1. Will caltracs benefit me for street driving?
2. Will they make the ride harsh?
 

AKlowriderZ71

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May 14, 2012
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Cal-Tracs also improve "instant center", which greatly aids traction by keeping your rear suspension loaded. When properly adjusted, they work very well.

 

Chevy1925

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Cal-Tracs also improve "instant center", which greatly aids traction by keeping your rear suspension loaded. When properly adjusted, they work very well.





Axle wrap bars change instant center as well. Look at sled pull truck on the old dodges with stock frames, they actually bend the frame not far from the axle wrap bar mounting point.
 

Brabham 64

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In my friends mud racing truck we always installed a swingable shackle hangar type setup on the front of the long bars that say the bars would still allow some movement/travel in the suspension. Do you think that would work in dd/weekend racer dmax?
 

Chevy1925

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In my friends mud racing truck we always installed a swingable shackle hangar type setup on the front of the long bars that say the bars would still allow some movement/travel in the suspension. Do you think that would work in dd/weekend racer dmax?

thats a triangulated axle wrap bar. two points are solid on the axle with a single point mounted to a shackle which is then bolted to a frame mount. This is what i run on my samurai crawler and tons of other leaf sprung crawlers. the advantage to it for a crawler is you can get away with just one, move it up higher than normal axle wrap bars, and it follows the suspension travel better. you can get away with a single on a dmax but id put some good bracing, use strong tubing, and use a 7/8th hiem at the shackle end.
 

duramax05blk

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Would cal tracs be a better choice for sled pulling over standard bars? I have seen a few lbz's in 700hp range flex the frame with standard bars. Does trucks stance make a difference in the function of cal tracs vs standard bars? by difference in stance i am referring to say stock keys dropped with drop shackles to say a 6 inch lift?
 

Chevy1925

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Truck stance will make a difference in axle wrap bars. Flatter the bar is to horizontal, the closer you are to 0 amount of anti squat induced. Cal tracs don't care unless your using blocks in the rear end for a lift but they also sell extended plates for the bars to bolt to. Those extended plates will change the leverage affect of the cal tracs a bit as well.

As far as sled pulling. I've seen a few guys run them and do well. I could t tell you what one will out do the other there as cal tracs were never designed for dirt and pulling
 

Forever

This 1 time, at band camp
Jan 4, 2009
363
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Utah
Truck stance will make a difference in axle wrap bars. Flatter the bar is to horizontal, the closer you are to 0 amount of anti squat induced. Cal tracs don't care unless your using blocks in the rear end for a lift but they also sell extended plates for the bars to bolt to. Those extended plates will change the leverage affect of the cal tracs a bit as well.

As far as sled pulling. I've seen a few guys run them and do well. I could t tell you what one will out do the other there as cal tracs were never designed for dirt and pulling

Chevy,

1. Will caltracs benefit me for street driving?
2. Will they make the ride harsh?
__________________
 

Chevy1925

don't know sh!t about IFS
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Oct 21, 2009
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Chevy,

1. Will caltracs benefit me for street driving?
2. Will they make the ride harsh?
__________________

your going to need to search that question on here. i can not answer that as you will have to justify that for yourself. some guys hate them on a dd, others love them. ride quality will be determined on the amount of preload you set in them
 

Hot COCOAL

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I'm running CALTRACS on my rig, and although I've not been in it for a while now, I don't remember the ride suffering at all from the installation, only that the rear end didn't bounce when doing a burn out and the axel didn't "walk" when starting from a stop when pulling a heavy trailer. I LOVE MY CALTRACS!!

I do keep them adjusted to where the upper bolt's are about 1/4" off the spring pack and "if" I was to be "racing it" I'd adjust them to have about a full turn into the spring pack, and yes, then you really feel the rear end bound down and "tight"