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Cranky
12-27-2012, 08:52 AM
Mopar torsion bars are preset at the factory in the direction of use. You can observe this preset by laying the bars down on a flat surface and observing how the bar is twisted. The driverís side bars will have a 30 degree right hand twist. A passenger side bar will have a 30 degree left handed twist. Pre-setting the bars in this manner improves the load carrying capacity in the pre-set direction. But, the load carrying capacity is reduced in the other direction of twist. This is why it is so important to get the bars installed on the correct side of the car.

Simple as that. The bars are generally marked but I still run across them from time to time that are installed wrong.

R-body_mopar
12-27-2012, 09:03 AM
Thanks, Cranky!

I could never figure out the markings on the bars, so anytime I ever removed them, I labeled them right/left, front/rear.......or marked them with paint........when I knew I needed to put them back the same way they came out..................:o

Of course.....IF somebody had previously put them in WRONG........I wouldn't know it! :o


Duh!

Cranky
12-27-2012, 03:42 PM
They are marked left and right with an 'L' and 'R' but I always thought that also designated that they were to be installed with the L and R at the back. Only one end is marked. Anyways, the bars I just took out of this low mileage 67 Coronet that has been sitting since around 1970 had the markings at the front.

dodgeboy8
12-27-2012, 05:53 PM
looking at it from the front or driver seat????
MP bars have no left and right marking!

CudaZappa
12-27-2012, 06:49 PM
Bars with 30* of clocking are generally L & R side until used. Torsion bars are a torsional spring, so they have the same rate being twisted clockwise or counterclockwise. Mopar production bars "new" have less (or more, depending on the twist) than 30*. If you look at a hex nut, and spin it 30*, you'll notice that the points are exactly on the center of where the flats just were. (or any odd multiple of 30). You re-install bars on the same side they were used on as the material actually deforms over the years and switching them side to side could impart new stresses on them.

Factory bars are stamped with the last 3 digits of the part number. Odd #s go on the left (driver's side). Also, they are marked L & R! There is no front/back to a torsion bar, but its general practice to put the p/n's to the rear of the car.

Also, non-standard mopar bars may have unique (or no) indexing. This may require "clocking" the torsion bar anchors in the unibody (covered in the chassis manual). Or non-standard installation.

Standard installation is to put the bars in with the Lower Control Arms at "full droop" and the torsion bar adjusters backed almost all the way out (as far back as practical, generally 1/8-1/4" protruding the adjusting block to find and sit in the arm recess. Sometimes this may require removing a bump stop or disconnecting one end of the shock absorbers.

Cranky
12-27-2012, 06:55 PM
I have several bars stored and they all have 'R' and 'L' markings. The first bars that I pulled was in 74 from a 72 Challenger and I can post a pic of the ones I just pulled....

dodgeboy8
12-27-2012, 06:57 PM
Thanks more info for my mind!

---------- Post added at 06:57 PM ---------- Previous post was at 06:55 PM ----------

I have 2 sets of mp's for the GTX .920's and the .810 drag race neither have L or R the .960 originals are long gone!

Cranky
12-28-2012, 09:09 AM
looking at it from the front or driver seat????
MP bars have no left and right marking!The front is always the front and the left side is always the left side :D :angel:


Thanks more info for my mind!
I have 2 sets of mp's for the GTX .920's and the .810 drag race neither have L or R the .960 originals are long gone!Never seen aftermarket bars marked L and R either....

Dons Dart
01-09-2013, 11:28 AM
looking at it from the front or driver seat????
MP bars have no left and right marking!
The new MP bars I just got have the L&R stamp.Lucky for me I guess