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Guys, I'm thinking about a rear sway bar for my '72. There are about a dozen mfg's so I need some advice. My only requirement is that it doesn't show. I want to be able to be behind the car and not see the bar hanging below the RE.

DSE has a really nice piece but it requires welding to the housing which would be fine but I've already powercoated the RE and it is installed. Thinking I'm limited to a bolt-on.
Any ideas?
Thx
 

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What are the symptoms that cause you to think about putting a rear bar on your car?
 

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Assuming the the vehicle has an independent front suspension and a solid rear live axle.

A sway bar whether front or rear wants to keep the body flat by tying the two wheels on a given axle together. In a drag race the launch is what’s being controled. A leaf spring setup will benefit from a sway bar as the forces at play on the launch are doing several things simultaneously. The suspension is loaded up just before you take off, the tires bite, the front end lifts, weight transfers to the rear, and the torsional forces from the driveline want to twist the the body and axle in opposing directions as they are propelling the car forwards. A rear sway bar will help keep these forces in check and maintain a fairly flat attitude and equally distribute the load the rear tires on to the pavement.

Where cornering is concerned, the forces at play are similar but with different priorities. Weight transfer is still a concern but the transfer is from side to side rather then front to rear. Depending on the front suspension setup you have the spring rate, shock, and sway bar choices you have in place will determine how much body roll you will allow the front suspension to articulate through a corner. As you approach a corner and set your corner entry speed, entering the you turn in to change direction, the body of the car will want to roll to outside of the turn and plant the front outside wheel with the highest contact patch load of the four wheels. The rear outside wheel will have the second most contact patch load, then the front inside tire, and finally the rear inside tire will have the lightest contact load allocated to it. If you have fairly stiff suspension with little to no articulation a rear sway bar will have little adverse effects on cornering but that makes for a pretty rough ride. Think of a little red wagon with no suspension the wheels are always in contact with the pavement and the ride is very harsh. The more compliant the suspension setup is the more articulation is allowed the more critical the rear inside wheel becomes. A rear sway bar can significantly reduce the contact load on the rear inside tire which is quite undesirable while cornering.. I prefer to keep a light rear spring rate, gas charged shocks, and no sway bar. Currently, my front springs are firm, shocks are gas charged, and I have a light front sway bar. The front doesn’t articulate a great deal but the rear complies to what the front end needs..
 

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1969 Nova . . 2dr . . Chino Valley,Az USA
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good thought . . . . . well said .

jim
 

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Hmmm. I wonder now if I’ll end up running my car without the rear anti-sway I made for it. It’s been a while and I honestly can’t remember why I thought I needed it. Testing should be fun at least.


Sent from my iPhone using Tapatalk
 

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Sway bars are terribly misunderstood. I'll give you the nickel explanation:

Add stiffer front bar, you will get more understeer or help to balance a car that has oversteer. Add stiffer rear bar, you will get more oversteer or help balance a car that has understeer.

Sway bars are a tool (one of many) you can use to tune & balance the car. If you've upsized the front sway bar, chances are you can benefit from adding a rear sway bar. If you have a stock sized front sway bar, don't add a rear bar as this will simply encourage oversteer.

When the car tries to roll in a corner, load will shift to the tires on the outside of the car to counteract the car's tendency to roll over. Roll stiffness and roll center heights dictate which end of the car will see this the most; the stiffer end of the car with the lower roll center will experience more of a load shift. The more this load shifts, the less overall traction that end of the car will have. The combination of the roll centers, springs, and sway bars will dictate how this happens for a given car.

David provides a good explanation of this here as well: camaro spring info

To the OP, all the aftermarket bars I've seen for these cars are axle mounted, which means they will be seen from behind. For example, I have a Helwig rear bar on my Nova (pictured below). It is very similar in design to the DSE unit, although I like that DSE includes some reinforcement plates for the frame which do not come with the Helwig unit. Overall quality on the Helwig bar is excellent and I feel it's a great bang-for-the-buck.



If you were willing to do the work, you could try to package a frame-mounted bar, but it would likely be a fully custom job. There just isn't much room back there to mount one.

I would make sure whatever bar you select is adjustable. Remember this is a tuning tool. If you autocross or track the car, you will likely want to make some adjustments.
 
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