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Discussion Starter #1
looking to put some front and rear sway bars on my 67 camaro...i was going to go with hotchkis but..i started looking at the addco bars and..thought i'd ask you guys what you thought....what's the big difference between a hollow sway bar and a solid??? as far as the price for the front bar...there's only a $40 difference between the addco and hotchkis but...on the rear sway bar the hotchkis is almost 3x's the price of the addco...just wondering if it's worth it or what's the deal with that....any info or suggestions would be most appreciated!!!!!
 

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Watch out on the rear bars. If you have a factory traction bar on your 67's rear, you have to cut the bracket off to use Hotchkis. Addco makes rear bars for with or without the factory traction bar.
 

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And be sure the rear bar is engineered to MATCH the front bar. I don't mean the same rate of resistance, but rather to balance the front and rear. A front-only bar usually leads to under-steer on a factory-stock car. That's for safety. A properly matched rear bar will make your car come alive. I still remember the rush the first time I tried out the rear bar in 1970 or so. Both F&R are Addco. The first picture is of the 1970 Addco that's now in their museum, the second is the new one they sent me for free. (Lifetime warranty)


 

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Discussion Starter #5
is there a difference in the front steering between a hollow bar and a solid??? overall...which one is the better one to go with?????? addco or hotchkis?
 

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The main reason for choosing a hollow anti-sway bar over a solid bar is weight savings. During cornering the right and left side control arms move in opposite directions from one another and place the sway bar in torsion (and partially in beam-bending at the ends). The torsional stiffness of a shaft is inversely proportional to the torsion angle(a) which is equal to a=(T*L)/(J*G) (where J is the polar moment of inertia). The polar moments of inertia of solid and hollow shafts are J=(pi/2)*(r^4) and J=(pi/2)*[(ro^4)-(ri^4)] respectively (ro= outer radius, ri=inner radius). As seen in the equation, the polar moment of a shaft (and thus the overall stiffness) is proportional to the 4th power of the radial location of the shaft material. In other words the steel near the outside of the bar does much more work than the steel in the center. If we consider a steel bar with dimensions of 42” long with 8” ends, the stiffness and weight for each would be as follows:

Bar Outer Diameter:​
1"​
1.125"​
1.198"​
1.25"​
Solid​
Stiffness (lbs/in):​
400​
641
978​
Weight (lbs):​
12.9​
16.4
20.2​
Hollow 0.188 wall​
Stiffness (lbs/in):​
339​
515​
642
744​
Weight (lbs):​
7.9​
9.1​
9.8
10.3​


As seen in the above table a solid bar of equal diameter will be more stiff, but not by much, and will weigh a good deal more than a hollow bar. I added the 1.198” OD bar just to show the size of a hollow bar of equivalent stiffness to the 1.125” solid. In my opinion, because this weight is added in front of the front wheels and is partially un-sprung weight, I would go with the hollow bar.


Thanks,
Mark
 

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Sorry about the table in the previous post. Here it is again...


Code:
Bar Outer Diameter          | 1”   | 1.125”| 1.198”| 1.25”
  ----------------------------------------------------------
  Solid  | Stiffness (lbs/in) | 400  | 641   |  N/A  | 978
         | -------------------------------------------------
         | Weight (lbs)       | 12.9 | 16.4  |  N/A  | 20.2
  ----------------------------------------------------------
  Hollow | Stiffness (lbs/in) | 339  | 515   | 642   | 744
  0.188  |--------------------------------------------------
  Wall   | Weight (lbs)       | 7.9  | 9.1   | 9.8   | 10.3
  ----------------------------------------------------------
 

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We get this question pretty often.

Sway bars work off of torsional force (twisting motion). Therefore, the material in the center of a solid bar plays little role in the resistance of torsional force. With this in mind, we have eliminated some of the center material and also moved some to the outside of the tube, where it is most effective. In turn, this produces a sway bar that is lighter in weight and just as stiff, if not stiffer than solid. For example, a 1'3/8" hollow bar is equivalent to a 1'1/4" solid. But the 1'3/8" hollow bar is 6% stiffer and 43% lighter than the 1'1/4" solid.

If you want to read more, check out the instructions
 

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Discussion Starter #10
thanks a lot!!! i've been doin some thinking about this and figured...if all the top suspension guys: global west, hotchkis, DSE are using hollow bars...it must be for a reason...so...i think i'll go with a hollow bar!!!!!! now...i'm using the hotchkis sport rear leaf springs on my 67 camaro....i was reading on global west and...they say they don't recommend using a rear sway bar on upgraded leaf springs...but...hotchkis designed their TVS kit with the rear leafs and a rear sway bar...what do you guys think of a rear sway bar??? do i need it?? will it give me a noticably improved suspension?
 

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thanks a lot!!! i've been doin some thinking about this and figured...if all the top suspension guys: global west, hotchkis, DSE are using hollow bars...it must be for a reason...so...i think i'll go with a hollow bar!!!!!! now...i'm using the hotchkis sport rear leaf springs on my 67 camaro....i was reading on global west and...they say they don't recommend using a rear sway bar on upgraded leaf springs...but...hotchkis designed their TVS kit with the rear leafs and a rear sway bar...what do you guys think of a rear sway bar??? do i need it?? will it give me a noticably improved suspension?
Good question. I am considering TVS also but not crazy about the idea that I'd have to cut the factory radius rod bracket off my original 12bolt to mount the Hotchkiss rear bar...
 

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Without a rear bar you will usually have a large amount of understeer. Some people like a car this way, and if you are just crusing around, it's probably OK. But if you want a car that is balanced and could Autocross or stay on line around back road curves, then get a rear bar. I have seen 1 or 2 posts where a rear bar caused oversteer. I fail to understand how this is possible on a "normal" installation that does not bind in roll. Every Camaro I've worked on needed a rear bar, and I've worked on and Autocrossed all generations of Camaros except the 5th gen. Global West does not make a rear bar, and I don't understand why not. They do make solid front leaf eye bushings, and I think if you use those, the springs get very stiff in roll which may explain their recommendation. They suggested no rear bar when we installed their Cat5's (spherical bearings in the leaf eyes) on our second gen and it didn't work at ALL!

I've used Hotchkis, Hellwig, and Strano bars, and they are top notch.
 
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