Coil spring (spiral) in a 1971 Dodge

[F4R/T]

Inner fenders are stamped sheetmetal not designed for the abuse of a spring pushing and hammering against it. It will fail, torsion bars are so good GM and Ram still use them. They offer lower ride and center of gravity, adjustability, easy service, options for spring rates, and the list goes on. Don’t reinvent the wheel tune it ... your car not mine. Kern Dog is pretty sharp on suspension and wheels, so is superbeemike. Tons of info here look around there are guys road course racing these and doing well with a lot of stock parts and a few tricks.

 

[dvw]

To me it appears to be well done. As far as extra load tearing stuff apart? Two things come to mind. First is this system is supplemental. So the extra load can't be that much. Second there are plenty of unibody cars that use coil spring mounting. Thefactory upper control arm mount sees plenty of load in stock form. Look at old NASCAR and drag aplications that wheelie. Would I do it? No, the torsion bar system works well. It's funny, many think a coil spring works by compression and magic. What really happens is the coil wire rotates and twists just like a torsion that is coiled up. The factory stuff has less unsprung weight. Get the correct bar and shock for the application.
Doug

 

[Runcharger]

Exactly: A coil spring is a torsion bar, just wound and anchored differently is all.
I think the dramatic increase in unsprung weight would make the suspension react more mushy which may make it seem like it rides smoother, it would handle worse though as it would react much slower. You could probably get a similar effect by adding 20lb heavier wheels on the car, of course 20lbs heavier wheels would change steering input just as dramatically by the centrifigul force they would apply, so that would be a separate issue.

 

[#41]

Sure its possible. You have seen it. What are you questioning? If you like it, just do it.

 

[JR_Charger]

To me it appears to be well done. As far as extra load tearing stuff apart? Two things come to mind. First is this system is supplemental. So the extra load can't be that much. Second there are plenty of unibody cars that use coil spring mounting. Thefactory upper control arm mount sees plenty of load in stock form. Look at old NASCAR and drag aplications that wheelie. Would I do it? No, the torsion bar system works well. It's funny, many think a coil spring works by compression and magic. What really happens is the coil wire rotates and twists just like a torsion that is coiled up. The factory stuff has less unsprung weight. Get the correct bar and shock for the application.
Doug

Wait, the original OP car still has the torsion bar? It does, doesn't it?

Seems like this is just taking the place of a quality shock then? But adding weight.

 

[JR_Charger]

Inner fenders are stamped sheetmetal not designed for the abuse of a spring pushing and hammering against it. It will fail, torsion bars are so good GM and Ram still use them. They offer lower ride and center of gravity, adjustability, easy service, options for spring rates, and the list goes on. Don’t reinvent the wheel tune it ... your car not mine. Kern Dog is pretty sharp on suspension and wheels, so is superbeemike. Tons of info here look around there are guys road course racing these and doing well with a lot of stock parts and a few tricks.

Some mechanics won't mess with Macpherson struts, unless it's a quick strut. Rebuilding those things can kill you.

That said, from what I gather the biggest advantage of the macpherson strut conversion is the switch to rack and pinion steering, but what rack and pinion unit are they using? Mustang II? Is that really better than a Borgeson steering box?

 

[autoxcuda]

It's just being used as a helper spring. Like rear air shock or those old load leveler rear shocks with coil spring around them.

It will put some more stress on the shock support. And more risk of cracking and breaking.

OR you could just put larger torsion bars in. Same effect.

 

[JGOMEZV]

Car is 'stiff' because the coil springs have added to the spring rate. Probably feels like a truck. Remove the springs & enjoy the softer ride....

My vehicle doesn't have that modification; it has its original lower control arms. The photo is a reference image of a different vehicle that arrived at my workplace. My Coronet Wagon has its original suspension.

 

[JGOMEZV]

My Dodge wagon coronet has 235/75/15 tires that are larger than the originals, and the Dodge Dart in the photo has tires of its traditional size and it looks great. The owner of the Dart in the photo tells me that its handling isn't worse than what people in the comments are saying; it handles well.

Exactly: A coil spring is a torsion bar, just wound and anchored differently is all.
I think the dramatic increase in unsprung weight would make the suspension react more mushy which may make it seem like it rides smoother, it would handle worse though as it would react much slower. You could probably get a similar effect by adding 20lb heavier wheels on the car, of course 20lbs heavier wheels would change steering input just as dramatically by the centrifigul force they would apply, so that would be a separate issue.

 

[JR_Charger]

It's just being used as a helper spring. Like rear air shock or those old load leveler rear shocks with coil spring around them.

It will put some more stress on the shock support. And more risk of cracking and breaking.

OR you could just put larger torsion bars in. Same effect.

From what I've heard, those air shocks have a tendency to break the shock mount off. At least if they're used to jack the car up.

How would you know how much "help" the coil spring is doing? I'm "guessing" the torsion bar does not tighten up linearly, and the spring does not match the rate of the torsion bar. The spring could be doing most of the work at some point. Or not. I wouldn't risk it on my car.

 

[JGOMEZV]

Sure its possible. You have seen it. What are you questioning? If you like it, just do it.

I'll try it because several mechanics here have recommended it to me; they say it lasts a long time and runs very well. I'll show you when I've done the work.