PST 1.03 torsion bars

[j-c-c-62]

After 20+ years of pushing online, mostly unsuccessfully, to at least upgrade to anything stock to over a 1"+ TB, I followed that suggestion by the biggest observation a 1+" bar owner will then have:
Did they go big enough? And you will never know

So far of the hundreds who finally made the leap, I have only read of one. And that one deserved more info, like were they running KYB's, a 25? profile tire, was suspension bottoming out, etc

 

[Kern Dog]

There is a guy that used to post at Moparts from Illinois...."Mopar Mitch".
Smart guy, he loved to race his Challenger. He was a big proponent of big torsion bars and ran a 1.22 size in his car.

 

[j-c-c-62]

There is a guy that used to post at Moparts from Illinois...."Mopar Mitch".
Smart guy, he loved to race his Challenger. He was a big proponent of big torsion bars and ran a 1.22 size in his car.

But everybody was afraid if they went from OEM HD .88 to ,96, their ride would be harsh, ride like a dump truck etc . Nobody would listen to Mitch. Of course, Mitch was on track competing, so no sweat off his back if they ignored him. IMO it's the best first initial most impactful upgrade followed by tires and then shocks.
My latest custom built TB is C body hex, B body length. 1.38", hollow.

 

[icetech]

I put 1.03s on my car and absolutely love how it rides.. the roads are **** here and this thing takes bumps better than my 2018 grand cherokee.. Also USCT frame connectors...

 

[HAHNAGON]

What size is your sway arm? Adjustable strut rods and the bigger 13/16 ain’t going to help it handle any better. If you want it to handle like a track car you’ve got to go bigger T-Bars, Sway Arms, Adjustable Upper A-Arms and stiffen the Chassis. I also suggest lowered spindles and rear leaf springs but I wanted ride over everything. I have everything you have in the front end, my Sway Arm is a 1 1/8 Hellwig and my shocks are Vikings and they are awesome and it doesn’t bounce. My boy is running the KYB gas adjust and while they are a great shock they are not even in the same ball park as these Vikings.

I use the Hellwig 1 3/8" front and addco 7/8" in rear. I do always add mopar XHD rear leaf springs and subframe connectors, plus I add my own version torque boxes. I know that is probably overkill, but I can't help it, I enjoy doing it. I do have spc tubular adjustable upper arms on the 70. Sounds like I need to try the Viking shocks??? I have never tried the 2" lower spindles and I think I want to try those or those ball joint lowering bracket that Chris Birdsong is making and selling. Anyone tried those yet?

 

[j-c-c-62]

"plus I add my own version torque boxes. I know that is probably overkill,"

Like wearing a belt with suspenders to hold up one's pants, redundant.
2" lowered spindles by any form mess with your roll center, it's not a given it will result in a better handling car.

 

[70ChargerRT]

"plus I add my own version torque boxes. I know that is probably overkill,"

Like wearing a belt with suspenders to hold up one's pants, redundant.
2" lowered spindles by any form mess with your roll center, it's not a given it will result in a better handling car.

On a stock suspension car maybe. On a stiffened chassis, with upgraded suspension Lowering these cars a few inches will have more positive affects for handling than negative.

 

[j-c-c-62]

Well, we disagree I guess on what is a given and what not is a given.
The readers here should also understand a 2" drop spindle does not mean one has to accept say 2" of chassis drop, alternatively they may choose to get/use only 1" of static drop and additionally gain another inch of compression travel, to stave off bottoming out, which is never a good thing.

 

[JR_Charger]

you make a good point about ride height.

I have 1.00" diameter Firm Feel torsion bars with tuned Bilsteins,

What is a "tuned Bilstein?"

 

[68 Sport Satellite]

What is a "tuned Bilstein?"

Purchased from Hotchkis some 10 yrs ago. They take off the shelf Bilstein shocks and modify the valving so they respond better for the weight/balance of our cars. Some estimates I've read say 15% stiffer. Later Hotchkis switched to offering tuned Fox shocks and not sure if they still offer the Bilsteins. I've never tried tuned vs non-tuned back to back to I have no idea how they compare, but they work well for my car.

 

[HAHNAGON]

Here is the part Chris Birdsong is selling. Lower ball joint/geomtery adjusting bracket. $350 a pair. Looks very interesting.

 

[j-c-c-62]

Here is the part Chris Birdsong is selling. Lower ball joint/geomtery adjusting bracket. $350 a pair. Looks very interesting.

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Or change the roll center.

As helpful as your drawing is in that a picture is worth a thousand words, it should be noted for everyday application, the body roll drawn is extremely to make a point I think would be fair to say..

 

[JR_Charger]

Here is the part Chris Birdsong is selling. Lower ball joint/geomtery adjusting bracket. $350 a pair. Looks very interesting.

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Seems like that would compress the shock 1.5" more than normal, and reduce suspension travel by 1.5"? But maybe you could keep your splash shield. It's not clear whether the car pictured has splash shields or not. Supposedly you can't use them with the 2" drop spindles.

 

[j-c-c-62]

Seems like that would compress the shock 1.5" more than normal, and reduce suspension travel by 1.5"? But maybe you could keep your splash shield. It's not clear whether the car pictured has splash shields or not. Supposedly you can't use them with the 2" drop spindles.

IMO you need to rethink that shock and suspension travel aspect. The LCA limits compression travel, it stays stationary at rest, and only the spindle moves up, thereby lowering the car.
Not sure why or what would happen if one used 2" drop spindles with this lowering bracket and the car had any size tire or fenders still in place. Splash shields are a minor concern in my world.

 

[Kern Dog]

That bracket ONLY fits a drum knuckle.
Remember guys, the proper term is NOT spindle. The spindle is the horizontal portion that the hub attaches to.

 

[JR_Charger]

IMO you need to rethink that shock and suspension travel aspect. The LCA limits compression travel, it stays stationary at rest, and only the spindle moves up, thereby lowering the car.
Not sure why or what would happen if one used 2" drop spindles with this lowering bracket and the car had any size tire or fenders still in place. Splash shields are a minor concern in my world.

I see. The upper ball joint would be 1.5" higher though, would that affect caster?

That bracket ONLY fits a drum knuckle.
Remember guys, the proper term is NOT spindle. The spindle is the horizontal portion that the hub attaches to.

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I've still got my drum knuckles installed. I bought a pair of the 2" drop spindles to replace them, but haven't gotten to it yet. It sounds like the drop bracket may be a superior option in some ways. Dr. Diff has a kit to bolt Viper calipers to the drum knuckle. It's only for the 11.75" rotors and pre-2002 Viper calipers, but those things are at least easy to come by. Not the solution for me, but could be great if you're going to stick with 15" vintage rims.

 

[j-c-c-62]

I see. The upper ball joint would be 1.5" higher though, would that affect caster?



I've still got my drum knuckles installed. I bought a pair of the 2" drop spindles to replace them, but haven't gotten to it yet. It sounds like the drop bracket may be a superior option in some ways. Dr. Diff has a kit to bolt Viper calipers to the drum knuckle. It's only for the 11.75" rotors and pre-2002 Viper calipers, but those things are at least easy to come by. Not the solution for me, but could be great if you're going to stick with 15" vintage rims.

I believe they intentionally moved the 4 paired holes offset to each other (front to rear), gaining some often-needed caster in the upgrade. However, I believe the thickness of the bracket adds a certain amount of negative camber, but maybe too much for a streetcar, don't know.

The "Knuckle" effectively becomes taller here and most feel that improves camber gain aspects among other things thru suspension travel. I don't know without mapping it out to be certain.
Another thing to consider when moving the steering arm relative to the spindle with wide rims, big offsets, etc, your TR ends can start to interfere with the rims. I have an 1/8" clearance on one of my cars with 18"'s and added a 1/4" spacer even to get that.

 

[JR_Charger]

In Mopar B-Body Performance Upgrades 1962-1979 Andy Finkbeiner says the Magnum Force 2" drop spindles allow for full suspension travel and don't affect the alignment. The only issues he mentions are interference issues with small rims that have big backspacing. He doesn't say anything about changing the roll center. I don't understand how lowering the roll center would change anything in a negative way, but suspension design is a complicated subject.

FWIW I'm in the build stage, but I've got the QA1 Kmember, adjustable strut rods, tubular LCA's, 2" drop knuckles (not yet installed), the QA1 front sway bar (planning to replace with one that can run through the Kmember), 18" rims. I've currently got the factory upper A arm installed, with reversed offset bushings, but I'm considering replacing with a tubular A arm. Not sure which one to get, there are a few on offer.

Needless to say, I'll be big disappointed if the 72 Charger doesn't handle well.

 

[JR_Charger]

I believe they intentionally moved the 4 paired holes offset to each other (front to rear), gaining some often-needed caster in the upgrade. However, I believe the thickness of the bracket adds a certain amount of negative camber, but maybe too much for a streetcar, don't know.

The "Knuckle" effectively becomes taller here and most feel that improves camber gain aspects among other things thru suspension travel. I don't know without mapping it out to be certain.
Another thing to consider when moving the steering arm relative to the spindle with wide rims, big offsets, etc, your TR ends can start to interfere with the rims. I have an 1/8" clearance on one of my cars with 18"'s and added a 1/4" spacer even to get that.

Did you have a custom wheel hub made to run your 18's?

 

[j-c-c-62]

Did you have a custom wheel hub made to run your 18's?

The car I am talking about here is a 72 A body Swinger mainly set up for track days, I'm using 18x10.5" AR Mustang knockoff rims. 5x4.5"BC and the mentioned 2" drop spindles.
There are basically 3 choices for hubs, OEM, Wilwood, and Dr Diff, weights are shown, Dr Diff are beefy enough for me, but the weak point IMO shared by all are the small OEM bearings, so definitely endurance racing is out. I upgraded to longer ARP studs not shown on the Dr Dff hub.