What size torsion bars for a 383 in a 75 Dart?

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Ricer

Ricer

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I have a 383 in my Dart with stock small block torsion bars. What do you guys suggest for larger torsion bars.
Thanks in advance
 
Go to my mopar.com, find the parts book for 67 to 69 dart. In there will be the part numbers for the various tortion bars, might even have the size.
 
Ricer said:
I have a 383 in my Dart with stock small block torsion bars. What do you guys suggest for larger torsion bars.
Thanks in advance
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In 1967 they used a .087 diameter bar which is the same as what was used in 340 and 360 cars. Later big block cars used a .089 diameter bar which are hard to come by.
 
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mcodecuda said:
In 1967 they used a .087 diameter bar which is the same as what was used in 340 and 360 cars. Later big block cars used a .089 diameter bar which are hard to come by.
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I think your decimal place is off a bit.

0.87" and 0.89" slightly less than 1" slightly more then 3/4"

My 67 dart has HD tortion bars.

And measure 0.89

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anything smaller then 1" is too small for a small block car in my opinion.. the added weight of the big block will want larger bars.
 
abodyjoe said:
anything smaller then 1" is too small for a small block car in my opinion.. the added weight of the big block will want larger bars
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The bar diameter and length sets the spring rate. Lower spring rate can be set to the same ride height as higher spring rate (within some limits.) The main diferences with a stiffer bar will be harshness of the ride and cornering performance.
 
Dana67Dart said:
The bar diameter and length sets the spring rate. Lower spring rate can be set to the same ride height as higher spring rate (within some limits.) The main diferences with a stiffer bar will be harshness of the ride and cornering performance.
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and?

a 1+ inch bar with a big block will be far from harsh. hell its not even harsh with a small block on the larger bars.
 
I have a 451 lowdeck, basically weighs the same as a 383, in my '72 Dart. It was far too mushy with .89" bars. I bought a pair of 1.03" from P-S-T (they may still be giving FABO members a 15% discount, too) and it was a night & day difference. Now the ride is firm but not harsh, and it corners as well as expected (with a big-block in the nose and small tires up front, anyway).
 
If I was buying new bars I'd go with the 1". With that said we built our old '67 Barracuda fastback with a 383/727 AND AC AND PS using stock small block handling package stuff (.87 torsion bars, small block sway bar). While not a canyon carver it drove nice. Shocks were just the old Monroes I had pulled off the GTS because I didn't want to go buy shocks.
 
abodyjoe said:
a 1+ inch bar with a big block will be far from harsh. hell its not even harsh with a small block on the larger bars
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No, not saying that. I would expect with more mass in the front end of the car a higher spring rate would be needed.

Im just saying if you like the feel of your ride now, no need to change it. If it is to soft go bigger, but just like the dopes who cut coils out of their coil suspension to lower their cars and end up shaking their livers out of their bodies, you can go too far. I dont think that 1 inch is too big.
 
Are you looking for it to handle?

I ran 318 bars in my 440 prior to going ALterK
 
I have .830's (6cyl) in my 67 notch back. 383 stroked to 500. Old mopar guys would buy .810's for drag racing.
 
I just put in 1.14" torsion bars from Sway-A-Way as I do track day/autocross type stuff, with an aluminum-headed small block up front the ride is still quite nice; not any more harsh than a typical modern car. It is a tad bouncy because I haven't put in proper shocks to match but it's really not all that different from when I had 1.0" bars before or the stock 0.8x" whatever 318 ones. In my experience the ride quality doesn't change nearly as much as you'd expect with stiffer bars.

With that said and assuming we're talking about the car in your avatar I'd go for something in the 1.0-1.08" range, I'm also a believer there's no reason not to run at least 1" with modern tires on these cars. It'll be a nice improvement from stock, IMO factory bar sizes are all way too small and it's because of the tires being designed for back then.

Unless you do want to drag race it then smaller bars will actually help weight transfer on launch and make total sense.
 
I'll be using my slant bars (if they look good enough) with a 470 stroker, should be a pretty light engine though & it's going straight for the rest of its foreseeable life. Also I have no experience with driving a big block a-body yet so take my 2¢ with a grain of salt. I do have 340 bars from mp & was going to use when I planned street strip
 
I put the 1.03" in my Dart with a 383. I was running the small block bars. Made a huge difference in ride, and is not harsh.
 
I run the PST 1.03" bars in my 440 Duster. I upgraded from the /6 bars that were in it. It's a night and day difference, between the new bars and a set of Bilsteins, it rides as nice as a modern day vehicle now.
 
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