Decent handling susp setup?

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I understand 15's are a huge limiting factor, but i really want to retain my dogdish hubcaps. If i could fet 18s i could put dogdishdd on i would be sold.

Moog bushings are on the order list

Thanks for the rec on the sway bars, i will put those on the list.

How stiff are the mopar circle track springs? Are they just like a stock HD spring?

I looked through your resto thread alot, i wNted to pick out the exact same setup but im stuck with 15's. I really like your duster.

Thanks! :thumbup:

The Mopar circle track springs have a 120 lb/in rate and use a reinforced front section for better spring control.

The stock rear rate for standard springs was 85lb/in, the HD springs are 110 lb/in. So, they're a little stiffer than the HD springs, but not a lot. The front section does improve spring control though. The description of the AFCO's that I run is pretty much identical to the Mopar circle track springs, and it's been speculated that the AFCO's are no longer available because Mopar Performance is selling the same spring as the Oval Track's now.
 
Lots of good ideas here, for a driver, as opposed to an Autocross car, I would go in this order as your budget allowed:
1. Bilstein shocks
2. Subframe Connectors
3. A front sway bar
4. Hotchkis rear leafs
5. Borgeson steering box
6. A rear sway bar
 
i can't remember where i read this but depending on your front suspension a rear anti roll bar can hurt handling.It's not as simple as buying everything bigger or just adding pieces.
..best to deal with Dick at Firm Feel or someone with lots of experience.
 
I have cooper Ultra Tourings on my 69 Valiant and they work really well for a 15" tire. Even in a straight line they hook better than the Mickey Thompson sportsman 26 x 10.50 I have for the car.
If you do run 225 60 15's they may rub on the front of your car until you move the fenders or set up the front suspension.
 

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I have cooper Ultra Tourings on my 69 Valiant and they work really well for a 15" tire. Even in a straight line they hook better than the Mickey Thompson sportsman 26 x 10.50 I have for the car.
If you do run 225 60 15's they may rub on the front of your car until you move the fenders or set up the front suspension.


Cool, im a big fan of cooper tires, ill ditch the bf goodrichs and get myself a set of cooper ultra tourings. How does a set of 255/60r15s on the back on 15x8s sound?
 
Im not into drag racing, just want a car i can actually drive. We have lots of nice curvy roads, while im not exactly going to go autocross racing, I would like to be able to have a little fun in them.
Fair enough. You'll want to setup closer to ralley setup than road course or even autocross. Autocross assumes relatively smooth surface, and gets some heat into the tires - also most competitors want a 'loose' setup which is not a good idea for real street use.

Right now i have SS springs in the rear. I would like something that levels the car back out and stiff enough to help in the corners. Any sug?
It helps to know what your car weighs and how much is on the rear springs. Then you can get the height you want using rear spring rate and free arch. Options include:
a. Rick E-berger & Co. along with others have had good success in dearching SS springs for road course/street. Look up the Green Brick, especially the low buck approach they took the first time they were successful (not the first time).
b. Made in the USA replacements for A-Bodies based on factory specs from Stanley Spring. You may be able to buy locally. Here's a retailer that will ship http://www.stengelbros.net/Plymouth-Leaf-Springs_c_226.html Notice that Plymouth and Dodge had different leaf packages depending on the car's configuration.
c. A company like Firmfeel or Hotchkiss with strong interest and experience with rwd mopar handling who have developed options that generally work for people like you.

Right now i have 340 torsion bars. I am thinking 1.03 bars from pst.
Probably a good move. 340 bars are OK with soft rear, but even on rougher roads, with todays tires, you'll probably be happier with a t-bar as stiff as 200 #/in or so.
Later on i wiould like to ad front/rear sway bars.
Actually, a front sway bar is the most effective thing you can do. I'd start with that.
Do not add a rear bar unless you've added front anti-sway bar and preferably also increased the torsion bars. Do not add a rear sway bar if the rear is already very stiff. When the rear's rear roll resistance is too stiff relative to the front, it will have a tendency to fishtail rather than plow. This will happen when traction is lost, which of course is the worst possible time to find out.

Am i on the right track for what i want to accomplish?
Basically yes. Good shocks are worthwhile, but not cheap. Front sway bar is a great bang for buck. Lowering the center of gravity and roll centers is good. Depending on your roads, 15" tires will be OK. If they're real bad, then maybe look at 15" rally tires, which provide pretty good grip over a wide range of junk, not cheap. Otherwise I think people have already provided good advice from their own personal experience. I actually run 70 series 14s on the street, 15s only for competition, but selection in 14s is worse than 15s.
 
Fair enough. You'll want to setup closer to ralley setup than road course or even autocross. Autocross assumes relatively smooth surface, and gets some heat into the tires - also most competitors want a 'loose' setup which is not a good idea for real street use.


It helps to know what your car weighs and how much is on the rear springs. Then you can get the height you want using rear spring rate and free arch. Options include:
a. Rick E-berger & Co. along with others have had good success in dearching SS springs for road course/street. Look up the Green Brick, especially the low buck approach they took the first time they were successful (not the first time).
b. Made in the USA replacements for A-Bodies based on factory specs from Stanley Spring. You may be able to buy locally. Here's a retailer that will ship http://www.stengelbros.net/Plymouth-Leaf-Springs_c_226.html Notice that Plymouth and Dodge had different leaf packages depending on the car's configuration.
c. A company like Firmfeel or Hotchkiss with strong interest and experience with rwd mopar handling who have developed options that generally work for people like you.

Probably a good move. 340 bars are OK with soft rear, but even on rougher roads, with todays tires, you'll probably be happier with a t-bar as stiff as 200 #/in or so.
Actually, a front sway bar is the most effective thing you can do. I'd start with that.
Do not add a rear bar unless you've added front anti-sway bar and preferably also increased the torsion bars. Do not add a rear sway bar if the rear is already very stiff. When the rear's rear roll resistance is too stiff relative to the front, it will have a tendency to fishtail rather than plow. This will happen when traction is lost, which of course is the worst possible time to find out.


Basically yes. Good shocks are worthwhile, but not cheap. Front sway bar is a great bang for buck. Lowering the center of gravity and roll centers is good. Depending on your roads, 15" tires will be OK. If they're real bad, then maybe look at 15" rally tires, which provide pretty good grip over a wide range of junk, not cheap. Otherwise I think people have already provided good advice from their own personal experience. I actually run 70 series 14s on the street, 15s only for competition, but selection in 14s is worse than 15s.

Thanks for all the info, ill start checking into a few of these things
 
While I agree that larger than a 225/60-15 fits on the rear. I don't recommend it for a canyon carving street car. Why? Improves the rear end grip only, promotes understeer. If there was a rear weight bias or bunches more power, it might be worthwhile to have rears wider than fronts. Also worthwhile for ¼ mile work.
 
I have a set of 4 Bilsteins on the way. I also have a set of circle track rear springs. I am speaking with firm feel and should hopefully have one of their front sway bar kits coming and will have them rebuilding my manual steering box.

Question on tires, I know that it promotes understeer but I just want something a tad wider to fill out the rear fenders. If looking at slightly wider tires should the object to just keep the rear tire height the same as the front?
 
For optimal handling yes, the closer the rear tire height is to the front tire height the better. You want the roll centers to be close.

The understeer can be corrected for if it's a problem, just run a larger rear sway bar. Or if it's adjustable set it more aggressively. Depending on your power levels it may not be a problem anyway.
 
While you guys are deciding on the suspension upgrades to make, consider one easy improvement - move the battery to the RR trunk. Front/rear weight distribution is very important and while you can't get it perfect in these cars, every bit helps.
 
Moving the battery is the last thing I would worry about. Tire choice, torsion bar and spring rates, shocks, sway bars etc make a MUCH bigger difference. Especially if you're running a newer style battery to begin with. Moving 30 lbs on a 3500 pound car is a pretty minor effect. I'm not saying it's not worth doing, but it would be pretty low on my list of priorities. For the record the battery on my duster is relocated to the trunk, but that had a lot more to do with it being in the way of the J bars I installed.
 
For optimal handling yes, the closer the rear tire height is to the front tire height the better. You want the roll centers to be close.

The understeer can be corrected for if it's a problem, just run a larger rear sway bar. Or if it's adjustable set it more aggressively. Depending on your power levels it may not be a problem anyway.

Awesome, thanks

How about rim width in relation to ture size? Should I just go with as wise as is recomended for a tire size? I know there can be alot of sidewall flex when trying to run a tire on too narrow of a rim.

Like on a 225/60r15 for the front what is the optimal rim width? 8 inches wide? Or does rin width not play as much of a factor as Im giving it credit for?
 
Rim... it does. Your on the right track.
For handling, run the widest tire possible on the widest wheel possible for the tire being used.

This allows the tire to be as wide as possible without the tire bulging due to an narrow wheel. It should be less, sloppy.

The fellas before me have given good advice and links.
 
I agree with 72bluNnblu that the battery is not the #1 issue. However, in the time you guys have spent dissecting all the possible suspension/tire/wheel combos available to a guy who plans only spirited street driving, the battery could have been relocated. 30 pounds from the front to the rear is a 60 pound difference. With over 15 years in short track racing, I can tell you that relocating the battery will make a difference. A battery relocation will be more noticeable to a novice driver than arguing over the brand of shocks for street driving. Just my opinion. Merry Christmas to all.
 
We'll have to agree to disagree. Sorry. Just between my current fleet of mopars I've run half a dozen different brands of shocks, in suspension set ups that range from bone stock to basically full autoX. All run on the street. Even the difference between bilsteins and hotchkis fox's was far more noticeable than the battery relocation, and that was by far the smallest difference between all the shock combos I've run so far. Even just running on the street.

And tires are an even bigger difference. Even a small tire compound change can make a big difference, let alone width and profile changes. The entire suspension set up has to change around a decent change in tire compound.
 
We'll have to agree to disagree. Sorry. Just between my current fleet of mopars I've run half a dozen different brands of shocks, in suspension set ups that range from bone stock to basically full autoX. All run on the street. Even the difference between bilsteins and hotchkis fox's was far more noticeable than the battery relocation, and that was by far the smallest difference between all the shock combos I've run so far. Even just running on the street.

And tires are an even bigger difference. Even a small tire compound change can make a big difference, let alone width and profile changes. The entire suspension set up has to change around a decent change in tire compound.

Edit:sticking with my bilsteins for now.

I know there have already been some suggestions but Anyone have any front sway bar comparison info? Cant decide between the helwig, hotchkis or the firm feel.
 
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I think he addressed this a little while back on the shocks...

For shocks the RCD Bilsteins would be fine. The Hotchkis Fox shocks are better for larger torsion bars like the 1.12's I run, but with 1.03's and those tires I think the RCD's would be more than up to the task.
 
Should i have just shelled out the extra $ for the hotchkis fox instead of the billsteins?

I know there have already been some suggestions but Anyone have any front sway bar comparison info? Cant decide the helwig, hotchkis or the firm feel.

All three have good hardware kits for a 74 duster with through the k-member sway bars.

Hotchkis is tubular/hollow, has nice stamped bar ends with formed cups, straight as it goes through the k-member.

Hellwig has tubular or solid. Bent through kmember for extra clearance. Bolt sway bar attachment hardware

Firm Feel offers solid. I think you can order tubular. Bent in middle and bolt in hardware.

Up to you to compare price.
 
I think he addressed this a little while back on the shocks...

I know he did but I started second guessing myself after he mentioned how great of a step up the hotchkis shocks are over the bilsteins. However I'm going to stay with them for now and might experiment with heavier torsion bars and fox shocks later
 
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All three have good hardware kits for a 74 duster with through the k-member sway bars.

Hotchkis is tubular/hollow, has nice stamped bar ends with formed cups, straight as it goes through the k-member.

Hellwig has tubular or solid. Bent through kmember for extra clearance. Bolt sway bar attachment hardware

Firm Feel offers solid. I think you can order tubular. Bent in middle and bolt in hardware.

Up to you to compare price.

Yea price is not my concern. I can get the hellwig for about half the price as the other two but I don't mind spending more money if the larger 1.5 bars are better than the 1 1/8 hellwig bars. Are the other two that much better than the hellwig?
 
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