6 cyl or v8 torsion bars?

-
H

Hemi331

Member
Joined
Apr 16, 2022
Messages
10
Reaction score
0
Location
Rochester
Question. I have a73 dart with worn out torsion bars when I replace should I replace the 6 cyl bars with v8 bars car now has 360 in it was 6cyl. Also who makes a good remain steering box. Thanks.
 
Bars are the same length, have different thickness shafts which gives them the “spring rate”. If mainly street used, would go with 1.03 or .98 bars.
 
abodyjoe said:
i'g go 1" bars at a minimum.
Click to expand...

Exactly. If you’re running radial tires and doing street driving get some 1” or larger bars and a good set of shocks. All of these cars were massively undersprung from the factory because of the bias ply tires, less than great shocks and the floaty 70’s ride quality comfort thing that everyone was pushing at the time.
 
72bluNblu said:
Exactly. If you’re running radial tires and doing street driving get some 1” or larger bars and a good set of shocks. All of these cars were massively undersprung from the factory because of the bias ply tires, less than great shocks and the floaty 70’s ride quality comfort thing that everyone was pushing at the time.
Click to expand...
Thanks guys. Anyone know about a good quality reman steering box?
 
Hemi331 said:
Thanks guys. Anyone know about a good quality reman steering box?
Click to expand...

Borgeon is the steering components I will buy when I get to it... smaller steering box gives you more room in the engine bay with headers.

(Edited for name)
 
Last edited:
Check Jegs and Summit if its a manual box
Last time I looked a new OE manual box was around $125
 
Hellrats said:
So what makes them dangerous?
Click to expand...

i don't know that they are "dangerous" if driven in proper fashion knowing that they are too light for a v-8 unless using the car for the track mostly.. the handling of the car on the street will greatly improve with larger bars for sure..
 
I’ve been running /6 bars on the street since the early 1990’s. It’s nowhere near unsafe. If you want to road race and such then you need bigger bars. If you want the best 60 foot times and straight line performance you want the least spring rate that will hold the front of the car up. Then tune with a double adjustable shock.
 
Hellrats said:
So what makes them dangerous?
Click to expand...

I think "dangerous" is probably a bit too strong of a word. But they make for lousy handling. It does depend on how the car is set up, but you have to be much more careful about ride height. If you lower the car at all from the stock specs you'll constantly be on the lower bump stops. More than you might think too, because the lower bump stops are progressive so it's not a big hard hit every time. I have literally told someone on this board that their lowered car had to be sitting on the bump stops the way it was set up. They didn't believe me. But when they checked, they'd be been driving the car with it literally sitting on the bump stops for years.

It just really reduces your handling ability. The body roll is severe. Any hard inputs like slamming on the brakes also causes the suspension to bottom out, which again lowers your chances of maintaining traction. If all you do is putt around, maybe it never comes up. But if you have to avoid an accident and try to turn sharply you'll bottom one side of the suspension, lift the opposite rear, and roll the body at an extreme angle in between. All of which reduces your traction, your ability to stop, and your ability to avoid whatever it was you were trying not to hit.

Hellrats said:
I would think any worn out bar work be dangerous then
Click to expand...

Worn out suspension is less capable than properly kept suspension, yes.

But I think you believe that as the spring gets old the spring rate changes, and that's not really true. The spring rates of all springs is set by the metallurgy of the steel itself. All springs tend to "sag" over time, they lose some of their shape. But how that effects the suspension depends on the spring. Like a leaf spring just gets flatter. That lowers the car, and depending on the shape and how the leafs are laid out can also change how the spring works mechanically. But normally it doesn't lower the spring rate substantially. When a coil spring sags it also lowers the car. But, because of the shape of the spring it also means the coils get closer together, and that increases your chances of coil bind. The spring rate also doesn't typically change much though, the metal itself is the same thickness, the number of coils remains the same etc...

With a torsion bar, the car just gets lower to the ground. The "sag" come in with how the hex ends are clocked, over time the hex offset changes and the car gets lower. But there's nothing to alter the spring rate. If you raise the car with the adjusters you maintain the same suspension characteristics. The issue ends up being that eventually you run out of adjustment and can't keep the car at ride height.

Rat Bastid said:
I’ve been running /6 bars on the street since the early 1990’s. It’s nowhere near unsafe. If you want to road race and such then you need bigger bars. If you want the best 60 foot times and straight line performance you want the least spring rate that will hold the front of the car up. Then tune with a double adjustable shock.
Click to expand...

Yeah, I think "dangerous" and "unsafe" are pretty strong words.

But if you think the handling of a car running radial tires on the street with /6 bars isn't bad enough to negatively effect your ability to avoid an accident, you're sadly mistaken. Those /6 bars had too little spring rate from the factory, even for a /6 car. Up the weight, add radials, and those light bars will negatively effect your ability to stop, steer, and maintain the traction you need if things get sketchy. It doesn't have to be a race or an autoX, and it doesn't matter how safe or experienced you are as a driver. **** happens, and when it does you will not have the handling ability you're going to want.
 
Scody21 said:
Bars are the same length, have different thickness shafts which gives them the “spring rate”. If mainly street used, would go with 1.03 or .98 bars.
Click to expand...
Yup, and add a front sway bar for greatly improved handling.
 
Brooks James said:
If you get 1 inch or Larger bars, and have headers, plan on some header tube dinging
Click to expand...

If you need to dimple the headers you probably would have needed to dimple the headers anyway.

For example, let's say you've got the .85" V8 bars and upgrade to the 1.12" torsion bars I have. So you take 1.12", subtract .85", and divide that in half because we're talking about the radius for clearance. That's .135", so, just over an 1/8" difference in clearance. So going from the smallest v8 bar to a bar larger than many would run on the street and you're talking about barely over an 1/8" difference in header clearance.

I'm not saying you won't have to dimple the headers. I'm just saying it's hardly worth considering. I did have to dimple the headers on my car, but I would have had to dimple them with .92" bars too.
 
I’ve not had any header clearance issues with the TTI’s running the 1.03 FF bars, or Z bar or 90* oil adaptor with the wix 51510R which is a big filter. but i am running the 73 up drag link, tie rods and brakes with the 72 down Firm Feel sway bar on a 72 down K frame. Only spot that’s really tight is the power master mini starter and header clearance, got a heat blanket on the starter and no room left.
 
72bluNblu said:
I think "dangerous" is probably a bit too strong of a word. But they make for lousy handling. It does depend on how the car is set up, but you have to be much more careful about ride height. If you lower the car at all from the stock specs you'll constantly be on the lower bump stops. More than you might think too, because the lower bump stops are progressive so it's not a big hard hit every time. I have literally told someone on this board that their lowered car had to be sitting on the bump stops the way it was set up. They didn't believe me. But when they checked, they'd be been driving the car with it literally sitting on the bump stops for years.

It just really reduces your handling ability. The body roll is severe. Any hard inputs like slamming on the brakes also causes the suspension to bottom out, which again lowers your chances of maintaining traction. If all you do is putt around, maybe it never comes up. But if you have to avoid an accident and try to turn sharply you'll bottom one side of the suspension, lift the opposite rear, and roll the body at an extreme angle in between. All of which reduces your traction, your ability to stop, and your ability to avoid whatever it was you were trying not to hit.



Worn out suspension is less capable than properly kept suspension, yes.

But I think you believe that as the spring gets old the spring rate changes, and that's not really true. The spring rates of all springs is set by the metallurgy of the steel itself. All springs tend to "sag" over time, they lose some of their shape. But how that effects the suspension depends on the spring. Like a leaf spring just gets flatter. That lowers the car, and depending on the shape and how the leafs are laid out can also change how the spring works mechanically. But normally it doesn't lower the spring rate substantially. When a coil spring sags it also lowers the car. But, because of the shape of the spring it also means the coils get closer together, and that increases your chances of coil bind. The spring rate also doesn't typically change much though, the metal itself is the same thickness, the number of coils remains the same etc...

With a torsion bar, the car just gets lower to the ground. The "sag" come in with how the hex ends are clocked, over time the hex offset changes and the car gets lower. But there's nothing to alter the spring rate. If you raise the car with the adjusters you maintain the same suspension characteristics. The issue ends up being that eventually you run out of adjustment and can't keep the car at ride height.



Yeah, I think "dangerous" and "unsafe" are pretty strong words.

But if you think the handling of a car running radial tires on the street with /6 bars isn't bad enough to negatively effect your ability to avoid an accident, you're sadly mistaken. Those /6 bars had too little spring rate from the factory, even for a /6 car. Up the weight, add radials, and those light bars will negatively effect your ability to stop, steer, and maintain the traction you need if things get sketchy. It doesn't have to be a race or an autoX, and it doesn't matter how safe or experienced you are as a driver. **** happens, and when it does you will not have the handling ability you're going to want.
Click to expand...
 
You must log in or register to reply here.
-

Back
Top