Front sway bar ideas: 1970 Charger

[Kern Dog]

Hello there,
For years I have thought about the principles behind the engineering of the hollow versus solid sway bars.
These are not new....I recall some Camaro and Firebirds from the 80s and 90s that had hollow front sway bars. They may have been used before that.
The reasoning for this is reduced weight.
The engineering states that the strength in the torsional resistance is directly related to the outer diameter and that the material near the center has almost no value. Given that, the center can be hollow and the bar can be lighter and still stiff.
Several companies offer hollow front sway bars for our cars. Hotchkis, Helwig, Firm Feel and maybe even a few others.
From what I can gather, with all else being the same, a hollow sway bar needs to be 1/8" larger in diameter than a solid bar to have the same rate.
Years ago, I modified a stock front sway bar from a 1973-1987 Chevy 1 ton 2 wheel drive. I chose this one because it was close to the stock 1970 B body bar and because it measured 1 1/4". Back in 2000, options were limited for sway bars. Buying and modifying the Chevy bar cost less than $75 back then.

[Kern Dog]

The shape of this modified bar was similar to a stock bar. In the picture below, the Chevy bar is black, an Addco 1 1/8" solid is gold and the small bar is a 3/4" unit from a 73 Duster, a very similar shape.

[Kern Dog]

I bought a QA1 tubular bar sized 1 1/4". Black is the QA1 below, natural steel color is the Chevy bar.
Check out the difference in weights.....

[Kern Dog]

Yeah.... 8 lb difference.
The Chevy bar wasn't a perfect fit but when I had regular style sway bar end links with urethane bushings, the slightly narrower bar was okay.

[Kern Dog]

The old end links looked like so:

[Kern Dog]

While I had the engine out, I replaced the end links with some like these....

[Kern Dog]

They are less forgiving for fitment because they are a direct mount....They have no bushings to distort or cushion the sway bar. The upside is that they do swivel due to their ball joint type construction.

[Kern Dog]

The finish of the QA 1 bar is great, the fitment is great. The car feels as solid as before yet I shaved 8 lbs.
Earlier, I changed from 11.75" Cordoba brakes and swapped in a Dr Diff 13" disc setup. That shaved 14 lbs. The Borgeson steering box dropped 14 lbs. I love it when I can make a performance upgrade that also includes a weight reduction.

[kent]

Great write up Greg. Breaking down different approaches, different budgets.

[tan top]

clever idea , like the look of the  bar end links 
interesting info thanks for sharing KD 

[pipeliner]

They are less forgiving for fitment because they are a direct mount....They have no bushings to distort or cushion the sway bar. The upside is that they do swivel due to their ball joint type construction.

Does that Qa1 have any spring in it at all? Looks straight as board in the pics where it ties in to the LCA.

[Kern Dog]

Spring in it?
Do you mean does it have any curve?
No. It is as straight as a stock sway bar, It does not have a curve in the center either but it fits and clears.   

[Kern Dog]

Here is a closer picture.

[pipeliner]

Spring in it?
Do you mean does it have any curve?
No. It is as straight as a stock sway bar, It does not have a curve in the center either but it fits and clears.   

I just pulled my factory bar out of my 70 and it has a curve in it right on the end and so does this Hellwig I'm replacing it with. I just figured it was supposed to be there for some reason. Thanks!!!

[Kern Dog]

I pulled and sold a 70 sway bar from my other Charger. I did not notice any bend at the ends of mine. My stock one for the red car has been gone over 20 years so I don't recall what it looked like. I'd love to see a picture of another one to see what you mean. The bend must be slight for me to miss it.

[kent]

I have the slight bends Greg on my sway bar off of my original 23k 70 500. No damage anywhere to be seen.

[70 sublime]

I have the slight bends Greg on my sway bar off of my original 23k 70 500. No damage anywhere to be seen.

Does the bend go down or up ??

[kent]

Had to go back and check out the pictures. Up. Certainly up.

[Kern Dog]

Wow, that is great. I didn't notice that before.
Maybe the bend accommodates for a stock ride height, while the aftermarket bar assumes a lowered stance?

[pipeliner]

Wow, that is great. I didn't notice that before.
Maybe the bend accommodates for a stock ride height, while the aftermarket bar assumes a lowered stance?

Like Kent said it's up but I figured the bend was for some kind of spring action in the bar itself kind of like rear springs in a car but I don't know. Like I said my Hellwig has it also 🤷‍♂️

[Kern Dog]

The lower the control arm hangs, the higher the ride height. A bar with a bend on the lever arms would be beneficial if the end link loop needed to be in proper alignment with the stabilizer link.
When the LCAs are closer to the car, the ride height is lower and suspension travel is often shorter. A bar at that point needs no bend.

[kent]

Exactly. Great job describing Greg it. I was sitting down last night, looking at the pictures. Flapping my hands and arms trying to cipher how the car would sit with and with out the bend.

[Kern Dog]

Thank you, My good Sir.....

[Back N Black]

Thank you, My good Sir.....

Do you have a rear sway bay on your charger?

[Kern Dog]

Yes, I have a 3/4" bar from an '83 Imperial. The FMJ cars used a frame mounted bar very similar to the OEM E body bar.