Caltrac operation on leaf springs

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moparspares

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Ok never had them and just curious about them working. What I know is that it is basically an adjustable bar that bolts from U bolt seat to front shackle that locks up preventing the axle wrapping up and trying to walk over the diff housing in racing situations. My question is do they then affectively stop the rear shackle from any forward movement if they are adjusted tight/preloaded. If it tightens everything up in the rear springs wouldnt you negate everything the spring does to give you a smooth ride when not racing. Is it something you constantly adjust to the ride you want.
 
I can partially answer this. I myself never operating a car with them. I do have a set ready to bolt on a Duster.

The rear shackle question I am not totally sure of. I can still, in my head see the rear shackle moving.

The spring has two functions. Stop axle wrap and hold the cars back half up. The ride quality may be diminished. But you still need the springs to hold the rear of the car up. Since that is the fact of the matter, the springs must still have an impact on ride quality.

For a drag race, street or strip, once you figure out where the bars are to be set, there should be no need to readjust them over and over unless your at the track looking for every mast millionths of a second to win. Changing race conditions would have you looking at everything anyway.

However, for a street strip car that isn't competing for the higher level bracket racing Wally, everything would be fine.

I would note that changing to different tires would probably have you tweaking the bars for best reaction and times at the track and perhaps the street if there is competing driving. Just by way of how one brand/compound tire works vs. the last tire used.

All knowledge gleaned from constant reading from the guys that have Cal Track bars in there cars competing or not.

I got my bars as part of a parts deal. There split mono springs are next.
 
I like you thought the rear shackle would still have forward movement, however I looked at a Cuda the other day that had them and I find it hard to see how the rear shackle would still move. That stiff bar of the caltracs looks like it prevents all forward movement. Backing that bar off would allow some movement but usually the bars are tight/preloaded.
 
As far as the understand it, the springs still bend. Which would mean the shackle moves. As long as the rear of the car can move up and down, there will be movement. Once power is out to the rear, the twisting action maybe stopped by the Cal Tracks but the spring still bends under power.

Is there a Cal Track user aboard?
 
The shackle still has to move because as the suspension goes through its travel the spring changes length. So it has to move.

FWIW, the faster guys run sliders back there. They usually weld into the frame rail and replace the shackle. Pretty cool but I'm not doing it on my car because I don't want to change the car any more than I already have.

So yes, the shackle has to pivot. Or you'll have binding. Like trying to run a ladder bar without a housing floater. The bars and springs have a different length so they move through different arcs. The floater allows the two different length parts to move in different arcs without binding.
 
The shackle still has to move because as the suspension goes through its travel the spring changes length. So it has to move.

Ok so now I understand that the arc of the spring will make the shackle move which I can see. So I assume 2 things. The rear shackle can only move backwards because that is the path of least resistance OR does the rear shackle movement forward only happens between rear shackle and the U bolt seat. Any further forward than that the Caltrac stops it. I have spoken to some that say basically Caltracs make the rear spring redundant and just a mechanism to hold the rear end in. That is not my view but I still would like to understand what happens to the rear shackle and spring under extreme acceleration with the Caltracs. I have looked on You Tube but cant see any footage pointed directly at rear shackle with Caltracs.

It also intrigues me that some Mopars with Caltracs Squat then move forward and some lift and propel forward but I suspect that has more to do with shock absorbers and thats probably for another thread.
 
This thread intrigues me. I have a new set of Cal tracks and the mono leaf springs that I was going to run on my 70, but I have been told that they are not really good for street use. Can anybody elaborate?
 
The shackle still works as it should. All of your "spring" is in the rear segment of the springs. I have sliders on mine. They move freely, smoothly, and will move front to rear with the caltrac bars and mono leafs installed. I have not had it to the track to see how the new setup works yet though.
 
I heard some complain and some have no issue with Cal Tracks on the street. I guess it is a tasters choice. Taste it and decide if you like the flavor it delivers.
 
Good video and as I suspected the rear portion of the spring still moves as normal. This has the sliders but the shackle should still do the same thing. All the Caltrac really does is stop the the front portion of the spring trying to walk over the diff housing. Simple but effective when you see them work.
 
This thread intrigues me. I have a new set of Cal tracks and the mono leaf springs that I was going to run on my 70, but I have been told that they are not really good for street use. Can anybody elaborate?

I've been mulling over this as well trying to decide whether to go with Caltracs or Ladder bars/coil overs. It seems pretty split as far as what folks recommend. There are pros and cons to each. I have driven as car with caltracs and think they're fine for street use.
 
I've been mulling over this as well trying to decide whether to go with Caltracs or Ladder bars/coil overs. It seems pretty split as far as what folks recommend. There are pros and cons to each. I have driven as car with caltracs and think they're fine for street use.


Me personally, if I wasn't going to use a 4 link I'd skip the ladder bars and just use the Cal-Tracs. I use the Competiton Engineering bars on my car. Will be working on the tune up here shortly. If you want more adjustability, look into the Asassin bars. Don't recall the name of the shop that makes them, but if you google them you'll find it. I'm not a fan of ladder bars. Limited adjustment, IC too short for almost anything.
 
I run these on my street 68 Dodge Dart. It is a 383 4 speed car. I have Caltracs and their Monoleafs. They run fine on the street. They do give you a stiff ride, but provide traction like no ones business. I have 225/70 15" street tires. It spins for about 10 feet and hooks. I adjusted them as recommended by caltracs and have yet to touch it in a year. The rougher ride doesn't bother me because I know I am not driving a Caddy, I am driving a hot rod. I love them.
 
The Assassin bars look like a good bit of kit. They look like they hang low though and would be worthwhile looking at how much ground clearance for street use.

The rougher ride doesn't bother me because I know I am not driving a Caddy, I am driving a hot rod. I love them.

Rides like an Imperial - Mopar Content
 
I have the CE slide a links. They came with a poly type bushing and an aluminum bushing. So far just using the poly bushing. On the drivers side I just took out the slack by hand, pass side I preloaded the bar 1 turn by hand. I have SS springs and Viking double adjustable shocks. 1.451 sixty Foot Kim
 
I have the CE slide a links. They came with a poly type bushing and an aluminum bushing. So far just using the poly bushing. On the drivers side I just took out the slack by hand, pass side I preloaded the bar 1 turn by hand. I have SS springs and Viking double adjustable shocks. 1.451 sixty Foot Kim


You have an aluminum bushing for the bar? I only got the poly bushing. I guess if you use the aluminum bushing you for sure wouldn't want any gap. That would rattle your teeth.
 
So far so good, it may or may not 60 ft better. I only have stock shocks on the front. I may change to a 90/10 for a test and tune later in the year, even though some ppl have had trouble with the back end unloading and loading loosing traction and time. Kim
 
The big positives for me were the consistency and the car would stay straight in the burnout box and leave straight everytime.
 
The big positives for me were the consistency and the car would stay straight in the burnout box and leave straight everytime.
I could see them helping in that way. That is one thing nice about them they are adjustable. My car was was dialed in with the SS springs. It took a long time to get it there. The calverts were very easy to work with and get them right. I will always use them now that I converted over . But its a lot of money initially to get every thing.
 
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