Are /6 torsion bars the same as 318?

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Jimcbmx45

Jimcbmx45

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I have a dart swinger and just pulled the /6. Do I have to get different tortion bars or can I leave them?
 
This is a suspension question. Welcome aboard.

You can use the /6 bars. The T bars control up and down movement, shock dampen the movement. Stock 318 bars are thicker for more control or less of a bounce in the car. I run /6 bars in my '71 Duster, B block 400. It's more set up as a heavy street hitter. If it was a driver, I would use at least the big block bars that came stock. If I was carving corners, I'd just go to the thickest bars possible.
 
Here's some info regarding various diameters.
 

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In most cases, no, cars with /6's have smaller bars than cars that came with 318's. Cars with A/C were usually equipped with the next size up though, so a /6 with A/C would get the smaller 318 bars while a 318 with A/C would often get 340 bars.

You don't NEED to get bigger torsion bars. Of course, your car doesn't have to handle well either. And your intended use of the car is very important in making any choices in setting up your suspension.

If this is a street/strip car with emphasis on strip, leave 'em. It'll suck in the corners, but weight transfer at the track will be decent. If it's a street car or regular driver, buy a set of 1" torsion bars (minimum) and join the current century with regard to handling. If you prefer well mannered handling and modern ride quality, go at least 1.03". If you're thinking about any kind of autoX or road courses, go at least 1.06", probably more like 1.12".

Handling with /6 bars is laughable, even in a /6 equipped car. Remember the stock spring rates were designed for bias ply tires and very little traction. The 1" torsion bars from Just Suspension are still pretty soft even with just a small block, but they're light years ahead of anything stock in regard to handling. It won't carve any corners, but if you're worried about the ride being too stiff they're a good choice because they ride soft. At least they did on my Duster. So soft, in fact, that I got rid of them. My car now has a 340 and 1.12" torsion bars with aftermarket sway bars front and rear, and it still isn't "too stiff" for the street. I use it as my primary transportation, and drive it almost everyday. Larger bars like that will need better shocks though.

The 1" bars from Just Suspension, and the 1.03" bars from PST are also less expensive than any of the Mopar Performance torsion bars in the stock sizes. Only way to go cheaper is to buy used or leave the stockers in there. And remember, in either of those cases your probably talking about using torsion bars that are 40+ years old with an unknown history.
 
My Dart Sport was originally a /6 but now has a 360...same block as 318. I have not changed the torsion bars and at first my headers would hit the ground (bumps). Then I added a big sway bar to the front end and my headers have dragged only once since. Changing torsion bars is not really necessary I found and a sway bar is cheaper and easier to change than torsion bars.
 
Sway bar does jack for suspension travel, its like a hinge attached at the bumper: when 1 tire goes up, the other tries to go up the same amount. This is important for cornering when the inner tire wants to raise. The sway bar acts as a torsion bar between the control arms, resisting twist just as the torsion bars do with the control arms front to rear.
A coil spring is actually a torsion bar wrapped in a coil. A thicker or stronger torsion bar resists twist more than a small or weaker metal one. They are all rated in lbs..
 
Okay yeah it had a/c so that would mean it's rated for a 318? So you think I should just do the sway bar?
 
For a "Driver", just add sway bars. If you like to do just a little sported driving every now and again, I'd step on bar thickness.
 
Like was said, you don't have, as in HAVE to change them. But with a teener in there, you probably gained about 100 hp.Your driving style will change.You will very quickly find the limits of that 6cylinder suspension;hopefully before you crash it.
So sooner or later you are gonna want to upgrade.If you are not tapped out, now is the best time, before you get bent.
 
At $239 the PST 1.03" bars are about the cheapest new torsion bars you're going to find. I think PST is still offering a discount to FABO members too. The Just Suspension bars were $200 when I bought my set, but I don't see them on their website at the moment.

It's really not that much money when you think about how it completely changes how your car handles. People spend hundreds and even thousands of dollars upgrading their engines and drivetrains, but get bent out of shape by a couple hundred bucks for torsion bars. It's like cheaping out on brakes. Your car's suspension is the thing that could make the difference between being in an accident or being able to avoid it, is that really what you want to cheap out on?
 
I don't understand why people think the car has to ride like a go-kart in order to "handle". Don't think you have to use 1.12" torsion bars. Some people say they like them. But they certainly aren't necessary. I think my 67 FB handles great ON THE STREET with .890 bars and front and rear sway bars. I used to run backroad rallies all the time, and keep up with sports cars.

Remember, the sway bars control body roll when you are cornering. The torsion bar is there to soak up bumps in the road, and control weight transfer (mainly under braking). Massively stiff torsion bars will help prevent nose dive on hard braking, which does lead to understeer, but you can get through a corner fast in other ways -- brake on the straight and gas it through the turns works better on these front-heavy cars, anyway.

A car that is sprung too stiffly for the road conditions (think of most county roads, for instance) will have one or more wheels unloaded a great deal of the time -- an unloaded wheel has zero traction. My philosophy for real-world roads (not "track day") is compliant springs and stiff sway bars with stiff bushings (or heim joints). But my FB ran very well at Willow Springs on the Mopar Spring Fling track day -- it was limited by HP (stock 273 4bbl), not grip or braking.
 
There are only 1 or 2 after-market brands. I recall one size is most popular and thus more available and cheapest (1" D?). Used factory parts can be much less. One guy at a local Mopar show had several sets on the table for $10/set, so I grabbed the thicker 4 bbl ones (0.87"D) for my 65 Dart 2 bbl (0.85"D), then moved those to my 64 slant (rebuilding both front ends anyway). But, some used ones are permanently sagged (twisted), and don't swap L & R to fix that. Early A's are lighter, which helps. In the same vein, if you lighten the front end your 0.85"D T-bars may become fine. One way is to ditch the beastly RV2 compressor for a Sanden. Others are aluminum radiator and condenser, aluminum heads or intake, ... Think long-term before changing. New heads is for V-8 guys, we would love an aluminum head for slants.

The factory spring rates were too soft and "boat-like" for present tastes. That was long before BMW's popularized handling for the general public. Current cars may have gone overboard with stiff suspension and rubber-band tires that give too authoritative a ride.
 
I'll side with Bill on this. Going to stiffer springs is not necessarily the way to handling happiness. Stiffer springs will cause the ride to be rougher. Softer springs don't necessarily mean a floating ride if stiffer shocks are part of the package. The handling challenge for a street car is to keep the tires stuck to the pavement while controlling body motions. What constitutes acceptable is going to vary from person to person.

I've found that the anti-roll bar limits the travel of the Mopar front end, especially on the downstroke or rebound. All the same, I prefer to have at least a front bar as thick as I can find.

According to a myriad of build sheets I have seen, 225 cars with factory A/C had the same T-bars as 318s w/o A/C. I've seen 318 cars w/ A/C using 340 T-bars. All the 340 cars I've seen, w/ & w/o factory A/C, had the same T-bars.
 
VDART said:
they also have an .810 bar for the very early a cars. Lawrence
Click to expand...
The .810 bar was not an OE bar, it was offered by Direct Connection/Mopar Performance
for drag racing applications. It is not recommended to run too small a bar on the street just
as too big. Smaller bars have to be "wound tighter" to support the same load as a larger one,
which results in a shorter life due to fatigue stress.As stated above,too stiff a bar on "real
world" roads results in a lot of airborn time for the tires,but the car will be much more stable
under braking and obviously cornering on smooth surfaces.Remember,just as fast as hi-rate
t-bars gain load on jounce,they lose it on rebound.Many of my favorite roads are winding and
full of crests,which my stock suspended horizon w/205/50vr15's could outpace my ShelbyZ
because the tires stayed on the road longer B4 taking flight.
If you're going to primarily cruise & drag your ride,you can wind the bars to the orig. ride
ht. and go.If you want better cornering a stabilizer bar is the first step, then by all means get
better bars, but unless you plan on track time .890/.910 are better all around picks.
cheers!! :coffee2:
 
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