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I have a 1969 351W with FMX that is making some serious wheel hop upon launch. I want to install some traction bars to prevent this problem but I'm not sure if the Competition Engineering Part #C2109 for mustangs will fit. Don't these cars use the same rear end housings/leaf springs, etc? I know the shocks are the same but I am not positive about the rear end and leaf springs.
 

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The Cougar's rear springs are only slightly longer than the Mustang but are otherwise identical. I don't see why the Comp Eng bars wouldn't work at all. I was planning on picking up a set myself for my windsor powered 69... :)
 

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I have a set of South Side Machine liftbar traction bars on my 68 XR-7. I was wondering if anyone had any opions on these - They've been on my car for about a month, but I haven't tested them out yet. I did have to modify these - the bolt pattern was way off. That's all - Chad
 

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Cougars and traction bars

Cougars and Mustangs are different in the ash end. Cougars have longer leaf springs. Cougars also use rear spring isolators (at least on 71-73s) so the bolt pattern is different as well. Mustangs have the rear end pads sitting directly on the leaf spring, whereas Cougars have a rubber isolator. The reason Cougars have the difference is for a supposedly quieter ride (less road noise transmitted directly to the chassis). Also, since the springs are longer and such, to get the pinion angle right Cougars also use an angle wedge.

I used to drag race both of my 73 Cougars. Alpha Cat has a set of J-bolt Lakewood tractions bars for a Mustang, but they needed to be lengthened so that the snubber would reach to the front spring eye. I just added on (welded on) an extension of the same size rectangular tubing, repainted them black, and was good to go. On this car I eliminated the Cougar spring isolators and mount the axle pads directly onto the spring ala Mustang-style, but I had to use a wedge to get the pinion angle right. You really don't want to put all of your acceleration torque onto the mail spring leaf where it is unsupported. Do yourself (and your springs) a favor and make them long enough to reach the spring eye. Otherwise you risk bending or breaking your main leaf (not a good thing!) My Beta Cat is all stock (i.e. no traction bars). However, it leaves the line so hard that the rear springs wrap up severely. The nose of the rearend smacks the floor. The balance weights on the driveshaft were trying to wear a hole through the floor! I have resorted to using a pinion snubber on this car since I wanted to retain a stock look.

BTW, Alpha used to run 12.80s @ 107mph on 7" slicks, and Beta ran 14.40s @ 95mph on street tires. Not bad for 3800# cars! I guess its safe to say that I was getting traction!
 

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Are the leafs on mustangs not as wide as on the Cougar as well? When I went to put a set of lowering blocks [for a mustang] on my cougar - the blocks were a lot narrower then then the width of the leaf springs- they looked like they would cause more harm then good, so I left them off. I decided I could always make my own later. When I went to put on my SSM traction bars [also for a mustang] the bolt holes were also too narrow, so I had to drill new holes. Narrower leaf springs on mustangs would explain why this occurs. - Or is my Cougar a freak! Thanks all - Chad
 

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rear leaf spring width

The actual width of the spring itself is the same from Mustang to Cougar (again, at least for 71-73). The rear spring for either uses the same bushings at either end, so if you wanted to go with Polygraphite, you can just use Mustang parts. Also, if you ever need rear shackles for your Cat, again they're the same as Mustang pieces.

The only thing that makes the Cougars really weird is that damn rubber isolator at the axle. This rubber sandwich, if you will, causes more grief in that it will hold moisture. When that collected moisture causes the springs to start rusting, the leaves are forced apart. When the leaves are forced apart by the rust formation, it can cause the center bolt (the one that holds the leaves together) to break. That bolt is also used to locate the housing on the axle housing. When that bolt goes, the housing is free to move fore and aft on the spring, and severe dog-tracking is a result. NOT a good thing!

But perhaps the worst thing that can happen is that if the bolt doesn't let go, the leaves will crack right at the bolt hole where the stress is the greatest. What happens then is the car will either sag since it has less spring actually holding up the car, or in the worst case scenario, the main leaf will crack. AlphaCat had booster springs on the shocks when I bought it as an attempt to take the cheap way out to try to restore ride height. If that main leaf lets go, you can literally lose tour rear end! Lose it like dropped out from under the car! Definately not a good thing. When I took Alpha apart to restore the suspension pieces, both main leaves were cracked. No wonder the thing handled weird.
 

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Traction Bars

Just a quick note on the South Side Machine Lift Bars. I have had them on wvcat for about 8 years now but when installing them the hole in the spring plate and the axle perch was way too big because of removing the insulators. I put a washer on the top of the spring bolt to center it in the perch and welded a washer inside the hole on the ssm bars to center them. I was able to reuse my stock u-bolts by using spacers under the nuts but they should be replaced because they are actually to long. Oh yeah one other thing.....they work great!!!! big difference in traction!!! I am running a approx 400hp 357w,AOD,and 3:73 posi.I can spin if I want but atleast I don't have the loss in traction in normal driving like I used to. I've been planning ti hit the track someday but haven'tmade it yet
 
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