Torsion bars the bigger the better???

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Hijack in progress....

Rusty, just saw your new tag line.
Carefully what you ask for...

Gynecomastia-FAQ.jpg


Hijack over.

Sorry just had to.
 
Assuming the length, metallurgy, and shape are the same, larger diameter only increases the spring rate, (as in stiffer) the ride height will be determined by the adjustment.

For the ride height the indexing on the hex ends also matter, especially with the large bars. You can get into a situation where the range on the adjusters isn’t enough if the indexing isn’t right. I think most of the stock bars are indexed 20*, usually aftermarket stuff over 1.06” or so for A- bodies isn’t offset at all.

You can over spring a car.

depends on weight and setup.

I run 1.14”. You need shocks to control stiff springs.

there’s autocross nationally competitive old Mopars running 1.25” T-bars (largest possible). It’s a ~3200 lbs E-body with lightweight components.

You can actually run larger than that!

Some C-body’s had torsion bars with a 1.41” hex. So the B-body NASCARs and some of the T/A and AAR cars used C-body anchors and custom bars. Firm Feel will still make you custom torsion bars, so, if you switched to C-Body anchors you could probably go all the way up to 1.4”. But that would be a wheel rate if like 750 lb/in!!!!

1.24” A-body bars would be a little north of 450 lb/in, which should be more than enough for even pretty serious road race cars.

But I agree, you can overspring for your set up. Tire compound and suspension travel matter.
 
The roads were a lot worse back then, nothing like the new asphalt we have now. Some of the back roads were just patches over patches, so that floaty ride made it a lot more tolerable.

If you think the roads are better now than in the 1960s you need to drive some of our California roads...
 
For the ride height the indexing on the hex ends also matter, especially with the large bars. You can get into a situation where the range on the adjusters isn’t enough if the indexing isn’t right. I think most of the stock bars are indexed 20*, usually aftermarket stuff over 1.06” or so for A- bodies isn’t offset at all.



You can actually run larger than that!

Some C-body’s had torsion bars with a 1.41” hex. So the B-body NASCARs and some of the T/A and AAR cars used C-body anchors and custom bars. Firm Feel will still make you custom torsion bars, so, if you switched to C-Body anchors you could probably go all the way up to 1.4”. But that would be a wheel rate if like 750 lb/in!!!!

1.24” A-body bars would be a little north of 450 lb/in, which should be more than enough for even pretty serious road race cars.

But I agree, you can overspring for your set up. Tire compound and suspension travel matter.

you have to use sectioned “C-body” lower control arms too.

I think those guy used the an early pre c-c-body large car torsion bar stuff. Like 58-64? Chrysler or imperial stuff. There’s at least a couple platforms in there.

was trying to figure that out with the guy that owns that NASCAR based Le-Mans Charger
 
If you think the roads are better now than in the 1960s you need to drive some of our California roads...
That's because CA would rather pay deadbeats to play nintendo then fix their infastructure that has not been maintained since the 60s
 
The correct answer: it depends.

How about some more info on your car, and the application?
Here’s where I want to do:
I already have kyb”s
Slant six torsion bars

Want:
Inch front sway bar
Rear stability bar
control arms
Good tires
Maybe four link
Racing sporadically mostly street and occasional road course
 
Wow. Well...you have had a fair bit of good advice on this post. There is PLENTY on here on other posts about the steps for good handling. If this is your final call, good luck. What happens next is on YOU.

You have to pay to play. If you are too tight or not able to take good advice given kindly, then that is on you. Cheers, out.
 
Here’s where I want to do:
I already have kyb”s
Slant six torsion bars

Want:
Inch front sway bar
Rear stability bar
control arms
Good tires
Maybe four link
Racing sporadically mostly street and occasional road course

Looks like you posted about this last month as well...

If you’re building a car for street use and even just decent handling the /6 torsion bars and KYB’s belong in the trash and not on the car.

For the rest of it you can look at this post. Keep in mind if road courses are something you’re going to do you’ll probably want larger than the 1.03” bars I list for basic street use. And the chassis stiffening will need to be done as well, because high speed road courses will put a lot of load on the chassis. I would put everything on this list ahead of a 4-link. Not because 4-links don’t work, but because you’ll need everything else to take advantage of them. You can do really well , even on road courses, just with leaf springs. And they’re a ton less expensive than a proper 4 link install

67 Barracuda- Brakes and suspension on a 5000 budget- advice needed
 
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Here’s where I want to do:
I already have kyb”s
Slant six torsion bars

Want:
Inch front sway bar
Rear stability bar
control arms
Good tires
Maybe four link
Racing sporadically mostly street and occasional road course

The issue i see with this is that you're outlining the parts you want, not the parts you need to accomplish the goal you're after.

I used to want a 5.0 ratio lever for my transmission.
Not because I needed it or even knew what it did, but because it was in the MP catalog.

The need for a rear bar is for tuning the suspension, same with front size. Build the car, run the car, does it oversteer? Understeer?
THEN you start picking bars.
With slant six t bars, it ain't gonna handle for ****.

You might build it and it is perfect, with no bars. (Not saying it's likely, but it's happened). This all depends on tires, spring rates, weight distribution, etc. Just cuz they make the biggest bar doesn't mean you need it. I don't run a rear bar on my car, and I run a factory front, and with my torsion bars, rear leaves, and mediocre shocks.... it's actually quite well mannered. Every car is different, every driver is different.
 
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I live in Michigan where the roads really suck, have 18's and the 1.06 Firm Feel Torsion bars and the Fox/Hotchkis Shocks. I doubt anyone would think it rides too stiff. I have RMS strut rods and Hotchkis control arms where there is NO bushing at all (spherical rod end), and poly lower bushings as well as rear spring bushings.
 
I have 1.08" sway-a-way bars, Hotchkis leafs and Hotckis shocks. The ride is amazing. I just put the shocks on the car, I had KYBs and the ride was terrible. I knew the shocks were the source of the problem from reading comments on this forum, but I'm upgrading things in stages. Now that I have good shocks, I kinda want a stiffer bar, but I doubt I'll get them any time soon.
 
I have 1.08" sway-a-way bars, Hotchkis leafs and Hotckis shocks. The ride is amazing. I just put the shocks on the car, I had KYBs and the ride was terrible. I knew the shocks were the source of the problem from reading comments on this forum, but I'm upgrading things in stages. Now that I have good shocks, I kinda want a stiffer bar, but I doubt I'll get them any time soon.

which Hotchkis shock did you put on?
 
which Hotchkis shock did you put on?

The non-adjustables. I had to wait over a month for them to come in. Still waiting on the Hotckis sway bar. I ordered the shocks and sway bar back in December. They say they are having some supply chain issues with raw materials.
 
The non-adjustables. I had to wait over a month for them to come in. Still waiting on the Hotckis sway bar. I ordered the shocks and sway bar back in December. They say they are having some supply chain issues with raw materials.

The aluminum bodied ones.

I have the older steel bodied RCD’s. Doest look like they sell them anymore.
 
you have to use sectioned “C-body” lower control arms too.

I think those guy used the an early pre c-c-body large car torsion bar stuff. Like 58-64? Chrysler or imperial stuff. There’s at least a couple platforms in there.

was trying to figure that out with the guy that owns that NASCAR based Le-Mans Charger

Yes this Nascar Mopar info is hard to decipher sometimes. What I believe is this, the Ray Nichels built B body cars used 37" torsion bars with C body sized anchors. I suppose running a bar shorter than the stock 41" made the rate higher with the same diameter. Now they also made bars LARGER than could be pushed thru the C body socket. I think the cars were built with removable rear anchors to allow the bars to be installed without removing the lower control arms. I'm assuming the cars that weren't built by Nichels also used this set-up so they'd be able to use parts from Chrysler or Nichels. The Chrysler kit cars were built using the stock 41" bar length. Some kit car bars were also larger than the stock 1.25" anchors and I believe also used removable rear anchors. I wish our street A,B, and E bodies came with removable anchors!
 
Here’s where I want to do:
I already have kyb”s
Slant six torsion bars

Want:
Inch front sway bar
Rear stability bar
control arms
Good tires
Maybe four link
Racing sporadically mostly street and occasional road course

Uh well you're so far from where you want to go it is tough to give you a final answer. My suggestion is to slowly work your way towards the goal. Probably best to put a big front sway bar on there and good tires if you can. A high quality tire that is a decent size will make a really big difference as will a big anti-sway bar. Big torsion bars aren't really required for what you're trying to do but you should move up to at least the 340 bar or maybe something slightly larger. The slant six bar is probably too soft for performance driving. The KYB shocks will not be your friends once you get the suspension dialed in so be prepared to say goodbye to them along the way. For a street car I'd recommend a big anti-sway bar, big brakes, Koni shocks and a modest size torsion bar. This assumes a 17 inch tire that is 225 or 235 wide.
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I have 1.08" sway-a-way bars, Hotchkis leafs and Hotckis shocks. The ride is amazing. I just put the shocks on the car, I had KYBs and the ride was terrible. I knew the shocks were the source of the problem from reading comments on this forum, but I'm upgrading things in stages. Now that I have good shocks, I kinda want a stiffer bar, but I doubt I'll get them any time soon.

Yeah the KYB shocks don't work with stiffer torsion bars. They have some sort of valving issue that makes them horrible with stiff torsion bars. With big torsion bars you need a really good shock such as Koni, Bilstein or Hotchkis. I run Koni shocks in all of my cars but Firm Feel likes Bilstein and the guys at Hotchkis hooked up with Fox to design some Mopar shocks that they like.
 
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