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'70 Front Sway Bar Recommendations? Discounts?

PurpleBeeper

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I've got a '70 Roadrunner and I would like to upgrade the factory front sway bar. Any suggestions? I've looked at Addco, Helwig & PST (advertiser on this site). This is street driven car & I'm just trying to get it to corner a little flatter on off ramps. THANKS!

EDIT: I do have a factory skid plate & I really don't want to cut/re-weld it. Is 1-1/8" be the largest front bar & can slide into the factory front swaybar hole in the k-member?
 
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I have run this Helwig bar on a couple cars and will again on my next one. Good price too. If you have the skid plate on the k-member you will have to cut the welds and spread it a bit to get it in, then weld it back up. I think the 1-1/8" will go without separating the skid plate, someone else might be able to confirm this.

https://www.sdtrucksprings.com/index.php?main_page=product_info&products_id=16955
 
I too am using a helwig bar, bigger than 1 1/4 though, I love it .. but I did come from no sway bar at all !
 
Keep the stock front bar. Add frame connectors and a rear bar. You will be surprised at the improvement. Just my opinion.
 
Any other suggestions? I already have frame connectors. My car leans a lot in the corners & I'm trying to make it safer.
 
Any other suggestions? I already have frame connectors. My car leans a lot in the corners & I'm trying to make it safer.
What's the numbers on your torsion bars, and is your ride height higher or lower than stock? A bigger sway bar may help, but I don't think it is the root of your problem. Also rear ride height and tire size makes a difference as to how much pressure your putting on your front suspension. Most of our old muscle cars were setup for straight line performance. Personally I try to keep my front suspension at stock ride height and the rear suspension slightly higher but no more than 1" higher. Weak front shocks, small block or /6 torsion bars with a big block, excessive rake all contribute to poor handling. In 71-74 a lot of the factory big block cars got a rear sway bar, just to help handling. Hope this helps.
 
What's the numbers on your torsion bars, and is your ride height higher or lower than stock? A bigger sway bar may help, but I don't think it is the root of your problem. Also rear ride height and tire size makes a difference as to how much pressure your putting on your front suspension. Most of our old muscle cars were setup for straight line performance. Personally I try to keep my front suspension at stock ride height and the rear suspension slightly higher but no more than 1" higher. Weak front shocks, small block or /6 torsion bars with a big block, excessive rake all contribute to poor handling. In 71-74 a lot of the factory big block cars got a rear sway bar, just to help handling. Hope this helps.
I can't remember the numbers, but it has the factory Roadrunner front sway bars. The front is a littler higher than stock (headers/potholes) and I'd say the *** end is maybe 1"-2" lower than the front. Maybe it's because I've been driving more modern cars, but it sure is leaning a lot in the corners.
 
I did rebuilt rear springs, subframe connectors, RCD shocks, 1" torsion bars, and the Helwig away bar. Handles beautifully and I love driving the thing. Doesn't lean much at all
 
I can't remember the numbers, but it has the factory Roadrunner front sway bars. The front is a littler higher than stock (headers/potholes) and I'd say the *** end is maybe 1"-2" lower than the front. Maybe it's because I've been driving more modern cars, but it sure is leaning a lot in the corners.
You need the rear to at least the same height as the front. Sounds to me that reworking the rear springs is in order or replacements. Weak shocks in the rear as well as the front will allow body roll. Certainly a rear sway bar will help. If it were mine i'd start with getting the backend up and work from there. These cars actually handled pretty well in the day. They are not modern cars for sure but should hold their own.
 
You need the rear to at least the same height as the front. Sounds to me that reworking the rear springs is in order or replacements. Weak shocks in the rear as well as the front will allow body roll. Certainly a rear sway bar will help. If it were mine i'd start with getting the backend up and work from there. These cars actually handled pretty well in the day. They are not modern cars for sure but should hold their own.
Thanks for your input. The rear SS springs are brand new & so are all 4 shocks (although they're just KYB). I am in the process of going to larger front/rear tires (tomorrow rears, fronts already on there). I added the 2" lowering blocks in back since the rear bumper was waist high. I have considered going to 1" lowering blocks because of other recommendations on this side (pinion snubber/floor clearance). I've also considered turning down the torsion bar screws a little once I'm confident the taller front tires will clear. I still have the stock Roadrunner front torsion bars.

OK, having said all that. Where would you start to reduce body roll in corners? Bigger front bar? Add a rear bar? Stiffer torsion bars?
 
Thanks for your input. The rear SS springs are brand new & so are all 4 shocks (although they're just KYB). I am in the process of going to larger front/rear tires (tomorrow rears, fronts already on there). I added the 2" lowering blocks in back since the rear bumper was waist high. I have considered going to 1" lowering blocks because of other recommendations on this side (pinion snubber/floor clearance). I've also considered turning down the torsion bar screws a little once I'm confident the taller front tires will clear. I still have the stock Roadrunner front torsion bars.

OK, having said all that. Where would you start to reduce body roll in corners? Bigger front bar? Add a rear bar? Stiffer torsion bars?

Having said all that, I really don't understand how SS rear springs made the rear waist high. Something is wrong in my mind about that. Turning the torsion bars down is going to make the front suspension softer therefore more body roll. A bigger front sway bar will definitely decrease body roll. A rear sway bar will help balance the whole car in corners. Stiffer torsion bars will allow you to have a lower front ride height and retain equal stiffness in the front suspension. To answer your question I would address the rear springs and ride height. I feel with the right springs you should not need lowering blocks and that would also address your pinion snubbed issues. Once you have that worked out I think everything else will fall into place. I hope I'm helping and not confusing.
 
Having said all that, I really don't understand how SS rear springs made the rear waist high. Something is wrong in my mind about that. Turning the torsion bars down is going to make the front suspension softer therefore more body roll. A bigger front sway bar will definitely decrease body roll. A rear sway bar will help balance the whole car in corners. Stiffer torsion bars will allow you to have a lower front ride height and retain equal stiffness in the front suspension. To answer your question I would address the rear springs and ride height. I feel with the right springs you should not need lowering blocks and that would also address your pinion snubbed issues. Once you have that worked out I think everything else will fall into place. I hope I'm helping and not confusing.
I think I see what you're getting at....I think. Here's some back story. On my first set of SS springs, the *** end went WAY up in the air & I put the front eyes in the upper holes of the SS front shackles. This lowered the rear, but threw my pinion angle off more than I could shim for.

Years later....I put in a new set of SS springs, but left the front the front eyes in the lower/stock holes & added the lowering blocks (remembering what had happened with my first set of SS springs years ago). fyi-I just put taller tires in the rear about an hour ago & the car now sits level. Maybe it's just because I've been driving a (*** cough *** lowered Mustang with sport suspension), but my wife is grabbing for something to hold onto in corners. I know the old Roadrunner will never handle like the Mustang, but are you saying to add stiffer torsion bars & a rear sway bar before I put in a larger front sway bar? I was thinking about doing the larger front sway bar first, so maybe I'm backwards in my thinking. I'm all ears.
 
I think I see what you're getting at....I think. Here's some back story. On my first set of SS springs, the *** end went WAY up in the air & I put the front eyes in the upper holes of the SS front shackles. This lowered the rear, but threw my pinion angle off more than I could shim for.

Years later....I put in a new set of SS springs, but left the front the front eyes in the lower/stock holes & added the lowering blocks (remembering what had happened with my first set of SS springs years ago). fyi-I just put taller tires in the rear about an hour ago & the car now sits level. Maybe it's just because I've been driving a (*** cough *** lowered Mustang with sport suspension), but my wife is grabbing for something to hold onto in corners. I know the old Roadrunner will never handle like the Mustang, but are you saying to add stiffer torsion bars & a rear sway bar before I put in a larger front sway bar? I was thinking about doing the larger front sway bar first, so maybe I'm backwards in my thinking. I'm all ears.

That's what I would do. Now that you have the car sitting right, I think you will now notice some improvement in the handling. True it will never handle like the new Mustang unless you go all out. If you want the suspension can be setup strictly for handling, but there goes your comfortable cruising. Your stock sway bar with the addition of a rear sway bar will help balance the car without sacrificing ride. Stiffer torsion bars will also improve your handling as long as you keep the ride height the same. Adding a larger front sway bar will stiffen the ride and improve handling, but on a 70 will probably require modifications to the K member. You can go to a 67-69 style sway bar but that will require changing the lower control arms for the different sway bar tabs.
I will tell you from first hand experience on my 68 Dart GTS that it handles like a slot car, but on the other hand it's fun for about 20 minutes. After that its literally beating me to pieces. Here is its scenario. 1&1/2" front sway bar, frame connectors, small 3/4" rear sway bar, SS rear springs, and stiffer torsion bars. Tires on all 4 corners have no more than 4" side walls and are 60 series. I competed in Autocross events for a couple of years with it. I guarantee it handles better than your Mustang. Just don't try to go on a cruise for 60-70 miles. With your Mustang you have a balance of ride and handling and I think that's what you are trying to achieve with the RR.
 
Don’t let stickers guide you. Lube well as Zerks may be gone in days. Bilsteins, Firm Feel, and USCartool made a world of difference. I like Hotchkis products but would not do again.
Handles well in the canyons for a big girl. Always warns me of immenent disaster.
D7FA7313-287B-4EC5-8442-95836E71D2F6.png
 
That's what I would do. Now that you have the car sitting right, I think you will now notice some improvement in the handling. True it will never handle like the new Mustang unless you go all out. If you want the suspension can be setup strictly for handling, but there goes your comfortable cruising. Your stock sway bar with the addition of a rear sway bar will help balance the car without sacrificing ride. Stiffer torsion bars will also improve your handling as long as you keep the ride height the same. Adding a larger front sway bar will stiffen the ride and improve handling, but on a 70 will probably require modifications to the K member. You can go to a 67-69 style sway bar but that will require changing the lower control arms for the different sway bar tabs.
I will tell you from first hand experience on my 68 Dart GTS that it handles like a slot car, but on the other hand it's fun for about 20 minutes. After that its literally beating me to pieces. Here is its scenario. 1&1/2" front sway bar, frame connectors, small 3/4" rear sway bar, SS rear springs, and stiffer torsion bars. Tires on all 4 corners have no more than 4" side walls and are 60 series. I competed in Autocross events for a couple of years with it. I guarantee it handles better than your Mustang. Just don't try to go on a cruise for 60-70 miles. With your Mustang you have a balance of ride and handling and I think that's what you are trying to achieve with the RR.
You obviously have more old Mopar suspension knowledge than I do, so I am going to take your advice & put in a rear sway bar first (probably after new bushings on the stock front sway bar). If needed, step #2 new/larger front torsion bars and step #3 (if needed) finally then look at a larger front sway bar. I'm trying to build a long distance cruiser, so I'm sold on your suggestions.

I remember many years ago (before aftermarket stuff was available) consider seeing if I could adapt a late 70's Cordoba rear sway bar to my '70 Plymouth because I noticed the rear end & frame dimensions were the same....just hadn't figure out exactly what to do with the iso-link rear suspension lower spring plates (with sway bar mounting holes in them if I'm remembering right). I believe the stock '71+ b-body rear sway bars are too wide.
 
I believe the stock '71+ b-body rear sway bars are too wide
You may be right on that, I had a 72 RR/GTX, that had a rear sway bar, but never tried it on anything else. I sold the car and it's now being restored. Maybe someone else knows if they will interchange. As you stated the aftermarket can supply a kit. Best of luck on making the RR handle like you want.
 
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