Moved the rear leaf springs in on my 1969 charger and looking for sway bar Ideas one person told me a circle track , you can cut it to length . I put a 345 rear tire on a 20x12 rim with 6 inch back space . and kept the inner factory wheel well . has over a inch of clearance on the inside tire to tub . I want to put a sway bar in and any shock recommendations ?? I put ESOP rear 2 inch lower leaf springs . wish I went with the EATON . car is now in front end shop getting dialed in I put all QA1 front control arms in. thanks

Firm Feel makes their sway bars in house, they might be willing to bend up a custom one if you provide the specs.

Other than that, without the basic dimensions no ones going to be able to offer any specific suggestions.

You want frame hung or axle hung?

Width from c-c on the leafs?

vertical clearance between the axle tube the the rim.

Best advice I can offer, short of custom made, is to measure what you have and go to the boneyard and start measuring what's there and see if something can be made to work.

Remember the narrower the mounting width the less effective the bar will be and you will likely need to upsize the diameter to get back the rate you are losing.

There are a lot of drag race anti-sway bar kits on the market these days. I'd take a look at them and find one that will fit in there. You'll need to do some basic fabrication work.

Any of the aftermarket, axle mount style of sway bars should work for this since they mount several inches inboard of the factory spring mounts and link to the subframe. It is only the frame hung, factory style bars that link into the original leaf position that may present an issue.

Pictures please, how was the handling affected?

Moving leafs inboard on a mopar typically reduces the effectiveness of the spring at a rate of 10# per inch. So even the big, weld in 3" relocation has a fairly minor impact on rates and thus, handling. FWIW, most coil over set ups sell springs in 50# increments.

that's 3 inches per side, ~60# change in rate, that's pretty substantial.

Sounds like we are not yet at the driving/testing phase.

My question was going to be,
how does one know they even need a rear sway bar at this point, based on info shared so far?

No, IMO, it is not.

30# per spring, 60# total for the axle. As a percentage of rear roll couple, its even less. I'd bet that are maybe 10-12 guys on this entire site that can feel that slight of change. Coil springs are only available down to 50# difference per side, which is only 10# less, on a single side, than the 60# total we're talking about. To change the entire axle spring rate would be 100# difference, 40# MORE than we're talking about. Lets put it this way, if you are a good enough driver to feel the difference in under/over steer between a full tank of gas and a half tank of gas, then you are good enough driver to feel a 60# spring rate change. The rest of us are simply mathematically masturbating.

Thank you!

Since rear bars are somewhere in the area of 100 in/lbs stock more than half that lost is substantial and if you can't feel 60 in/lbs why bother with a bar at all cause you wont feel 100 either. Nor would having adjustable mounting points on the end matter, because you won't feel that change either.

This segment of the discussion was all about how relocation of springs impacts handling. My answer is its a minor change. You average mopar leaf spring is around 140-160# spring rate, more if you have SS springs. Moving it inboard removes 10# or 30# of rate, depending on which kit you use. While we both agree that softens it slightly, we disagree on the magnitude of that change and now you are now including roll resistance into that discussion. Okay, fine. Part of the roll resistance of a mopar leaf spring is imparted by its 2.5" width. This is not directly related to its spring rate and is more difficult to quantify, but, moving the leaf inboard does not change the width of the leaf pack, nor this resistance to leaf twist, or body roll. If you are talking about post 71 B Bodies, E bodies, or F bodies, the mounting angles of the leaf also are part of the roll resistance formula. So we are still left with a relatively minor change in the applied spring rate. Changing springs is pressure on the tires, similar to adding or subtracting gas to the tank. A 30# change in spring rate is like adding or subtracting half a tank of gas. Simple spring rate change. Can you feel it? A few can, most cannot.

Regarding anti-sway bars; Stock bars do not have adjustable mounting points. They also are no bigger around than your small finger. Don't mix those in with adjustable sway bars nearing or exceeding 1" in diameter or of tubular construction. The aftermarket bars that are much larger or offer adjustable points tend to have rates well over 220#. If you know much at all about roll resistance, than it goes without saying that small changes in sway bars have a much bigger impact that similar small changes in spring rate. The same applies to torsion bar diameter changes vs coil springs suspensions. For example; a .125" change in sway bar diameter could have the same impact as a 150# change in spring rate when it comes to roll resistance. So the incremental changes in sway bar mounting locations have a much bigger impact on the feel of roll resistance than a similar change in spring rate. In other words, each one of those holes in the adjustable bar is like adding or subtracting another whole tank of gas to the car whereas just changing spring rates is like changing half a tank of gas. Which do you think is more noticeable?

To summarize;
1 - moving leafs inboard creates changes to applied wheel rates
2 - leaf width and mounting angles are factors in roll resistance
3 - Anti-sway bar diameters and connecting points may have a bigger impact on handling than spring rates