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WHAT TORSION BARS TO RUN

Posted By: moparbud

WHAT TORSION BARS TO RUN - 01/04/09 02:32 AM

can any one tell me what torsion bars to buy for my 68 roadrunner drag car i have ladder bar rear and are mopar performance ok summit has .920/.960

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Posted By: Mike Swann

Re: WHAT TORSION BARS TO RUN - 01/04/09 02:44 AM

To me it really depends on the power. If you have a lot, most guys limit the downward travel to keep the front end down. real "springy" torsion bars for for lower powered applications were the car needs help getting the weight transfer on the back tire. Another issue is a lot of street use and potential oil pan damage. Looks like you have a big block in a B body, this usually works good. I would stay with the 0.960 IMO.
Posted By: blownzoom440

Re: WHAT TORSION BARS TO RUN - 01/04/09 02:51 AM

i am wondering what spring rate you have on the4 back?
another place to buy torsion bars is P-S-T.com
performane suspension technology montville NJ 07045 800-247-2288
Posted By: moparbud

Re: WHAT TORSION BARS TO RUN - 01/04/09 05:04 PM

i am not sure what spring rate is on the rear. this is my first ladder bar car. and trying to learn it all. thanks guys for your help. any info or advice is greatly appreciated.

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Posted By: blownzoom440

Re: WHAT TORSION BARS TO RUN - 01/04/09 05:26 PM

not sure if you can read the chart on the bars rating#.

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Posted By: Anonymous

Re: WHAT TORSION BARS TO RUN - 01/04/09 11:31 PM

Quote:

i am not sure what spring rate is on the rear. this is my first ladder bar car. and trying to learn it all. thanks guys for your help. any info or advice is greatly appreciated.




Here's a great Web site to learn............Billy recommends having the stiffest bar in the right front and the weakest bar in the left front to get equal tire loading........
Posted By: moparbud

Re: WHAT TORSION BARS TO RUN - 01/05/09 01:09 PM

i was told to run the torsion bars the same on both sides. with a ladder bar car. but maybe not. thanks for your help guys

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Posted By: blownzoom440

Re: WHAT TORSION BARS TO RUN - 01/05/09 08:45 PM

i would noy run 2 different bars.do you have any bars in it now?
are the LCA modefied?
i run 1" bars in mine but i have a lot more weight than you up front it looks like. do you know how fast you intend on going?wheely bars?
Posted By: Sport440

Re: WHAT TORSION BARS TO RUN - 01/05/09 11:35 PM

I would run the 440/hemi resto bars .920 I think the .960 bars will be to stiff for your lightened front end mike
Posted By: Troy

Re: WHAT TORSION BARS TO RUN - 01/06/09 12:46 AM

"Stored Energy" is what your looking for and a .920 bar will not do it. You want the newest and the smallest bar you can get your hands on. In a perfect world you want the bar turned all the way up just so the body is just off the bump stops (and that is with the bump stops shaved down to less than an inch thick) You can always control compression and expansion with the shock and limiters.

Just my opinion.
Posted By: blownzoom440

Re: WHAT TORSION BARS TO RUN - 01/06/09 12:57 AM

Quote:

"Stored Energy" is what your looking for and a .920 bar will not do it. You want the newest and the smallest bar you can get your hands on. In a perfect world you want the bar turned all the way up just so the body is just off the bump stops (and that is with the bump stops shaved down to less than an inch thick) You can always control compression and expansion with the shock and limiters.

Just my opinion.



if you tell us where to get them i think we would both try them.
Posted By: Sport440

Re: WHAT TORSION BARS TO RUN - 01/06/09 02:26 AM

Quote:

"Stored Energy" is what your looking for and a .920 bar will not do it. You want the newest and the smallest bar you can get your hands on. In a perfect world you want the bar turned all the way up just so the body is just off the bump stops (and that is with the bump stops shaved down to less than an inch thick) You can always control compression and expansion with the shock and limiters.

Just my opinion.





While I like the idea of stored energy! Ive seen the effects of to small of bars. The smallest isnt always the best.

Did I ever tell you the story about the 3 bears. mike
Posted By: Thumperdart

Re: WHAT TORSION BARS TO RUN - 01/06/09 03:55 AM

I`m running 30 year old 6-cyl bars and they seem to be working ok.

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Posted By: Sport440

Re: WHAT TORSION BARS TO RUN - 01/06/09 04:48 AM

Quote:

I`m running 30 year old 6-cyl bars and they seem to be working ok.





See, Thumper knows the story about the Three bears Too!

As the 6-cyl bars Arent the {thinnest} bars available.

There are {Drag bars} thinnest. And {6-cyl bars} thicker. And {318/340 cyl bars} thicker yet.

So its not always about just getting the Thinnest bars you can get

Its about getting the bars that are more optimum for your combo. mikre
Posted By: Thumperdart

Re: WHAT TORSION BARS TO RUN - 01/06/09 05:07 AM

The thin mopar performance bars didn`t work as good as the 6-cyl bars do.

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Posted By: moparbud

Re: WHAT TORSION BARS TO RUN - 01/06/09 05:07 PM

yes i do have bars in it now it was that way when i got it. the left is smaller then the right. and i have not run this car yet. and just looking to get the right stuff before i go run it. you guys are great and thanks for your help.

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Posted By: Troy

Re: WHAT TORSION BARS TO RUN - 01/07/09 10:18 PM

Lets talk about the B body first....
B Body are hard because Mopar no longer sells the old P5249156 .840 bars. I would look and see what the after market has. B Body's can be made to work very well but the learning curve is long. You have to have a very consistent engine,trans and rear suspension to be able to fine tune the front suspension. Trying to do this on a fresh chassis is hard to say the least.

Here is a picture of a customer of mine. Chuck Steinbeck has ran this car in D, E and F and has done very well but 10lbs and a 1/2 turn on his shocks makes a big difference. IF I remember correctly these are the some .840 bars.

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Posted By: Troy

Re: WHAT TORSION BARS TO RUN - 01/07/09 10:35 PM

A body cars......
I believe A body's are a little easyer to play with. Shorter wheel base....less overhang on both front and rear plays a big roll. When Darren Smith (last years world champ) was building his Dart we went through about four sets of bars and a few others that were home made. ( ) We played with spring rates, tapers and everything that we could think of. We learned that you can not compare the spring rates of a coil spring to that of a torsion bar. I thought that was strange but we came to the conclusion that the length of a torsion bar and length of a coil spring (if you unwound it) plays a big roll in spring rates. The bottom line was.....for a very long time Darren ran the MP .840 bars and they worked very well.

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Posted By: Troy

Re: WHAT TORSION BARS TO RUN - 01/07/09 10:52 PM

My old street car (iron headed 440 Duster) being a street, strip car, I ran the .870 bars. This gave me good street manners and yet, when I pulled up hard on the front end....with my hands....the front would rise over seven inches!! Most cars will never do that.

The things I do not like about old, used torsion bars (junk yard 6 cylinder bars) is metal has a memory. It has a natural state that it wants to stay in. When you have used bars the memory or the spring rate start to go away. A new "happy" bar, when installed and tighten up wants to raise the front end up but the weight of the car keeps it down. When you launch the car the momentum and the torsion bars try to pick front end up and put more weight over the rear. When you have week bars....the bars don't want to go up....there is no "spring" left in them so you get no help at all.

I will say this, every car is different and acts different. Sometimes older bars do work in a car but I have to ask my self why??

just my
Posted By: Thumperdart

Re: WHAT TORSION BARS TO RUN - 01/08/09 01:14 AM

My OLD 6-cyl bars are working pretty well I would say...WAY better then the thinnest mp bars but, is there another bar out there for my dart that would work better? If so, I might look into it...

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Posted By: jcc

Re: WHAT TORSION BARS TO RUN - 01/08/09 01:57 AM

Quote:

"Stored Energy" is what your looking for and a .920 bar will not do it.

Just my opinion.




I disagree with that opinion. The stored energy is exactly the same regardless of the bar diameter. The real difference that most are looking for is the amount rotation that a bar needs to completey release that stored energy, which is also a factor of time, which means a smaller bar keeps lifting the front end with a smaller force, long after a heavier bar has quickly released its stored energy, although with exactly wthe same amount of energy
Posted By: larry890

Re: WHAT TORSION BARS TO RUN - 01/08/09 02:14 AM

I had the torsion drag bars in my 68 gtx when i had ss spings on the car and they were great, but when i switched to ladder bars i had to put the 920 torsion bars back in to get the 60ft times back it was instantly better. we tried alot of tuning before going back to the 920 bars.
Posted By: Sport440

Re: WHAT TORSION BARS TO RUN - 01/08/09 06:19 AM

Quote:

Lets talk about the B body first....
B Body are hard because Mopar no longer sells the old P5249156 .840 bars. I would look and see what the after market has. B Body's can be made to work very well but the learning curve is long. You have to have a very consistent engine,trans and rear suspension to be able to fine tune the front suspension. Trying to do this on a fresh chassis is hard to say the least.

Here is a picture of a customer of mine. Chuck Steinbeck has ran this car in D, E and F and has done very well but 10lbs and a 1/2 turn on his shocks makes a big difference. IF I remember correctly these are the some .840 bars.




Troy, on this massive wheelstand shot I would think his combo could benifit from a thicker bar.

mike
Posted By: Troy

Re: WHAT TORSION BARS TO RUN - 01/08/09 07:05 AM

Good Eye
That picture was taken when we were testing. Look at the second picture with the silver Dart....the green Road Runner in the other lane is Chuck's car!! The only difference ( if I remember correctly) is a shock adjustment and a little weight but the same bars.....big difference with a better 60'.

I'm not going to say that the smaller bar is always better but me personally, I have had better luck going in that direction than a larger bar.

PS...take a close look at both Darren's and Chuck's car......look at how little the front wheels are hanging down. The wheels stand are also controlled by the limiters holding the wheels up.

One thing that I learned early on is it is not just one or two parts that is going to make the difference, it's the complete package that make it all happen.
Posted By: moparbud

Re: WHAT TORSION BARS TO RUN - 01/08/09 01:12 PM

thanks guys the info is great

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Posted By: wildcargo

Re: WHAT TORSION BARS TO RUN - 01/08/09 01:29 PM

Well I can tell you that a bar that has had a hard life,can be used up.
I had 6cyl bars and drilled shocks, worked good untill we mad the trip down to VMP about 400 miles down 301 with them expansion strips. The car bounce all the way down on the trailer and the bars were like wet nondles lost all there stored energy. I guess I should have put some real shocks on for towing. I would get some new bars not junkyard bars.
Posted By: Troy

Re: WHAT TORSION BARS TO RUN - 01/08/09 07:28 PM

Troy, on this massive wheel stand shot I would think his combo could benefit from a thicker bar.

mike


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Here is a picture of the same pass after she hit the ground. OUCH!!

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Posted By: blownzoom440

Re: WHAT TORSION BARS TO RUN - 01/08/09 07:47 PM

it looks like it needs a better shock or stiffer setting.
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