Triangulated 4 link sway bar

Dicey58

Well Known Member
Supporting Member 1
Hey guys,
Looking for some ideas or opinions on what I should do for a rear sway bar on my 58 Impala. Frame has been back-halved, narrowed over the axle, triangulated 4 link installed and 9" narrowed with provisions for coilovers. Obviously a lot has changed back there and a traditional sway bar setup isn't going to work. I apologize for the crappy pics, as I took most of them on my back under the car without much room. Any ideas as to where to attach to the 9"(it seems most of the room is dominated by brackets for 4 link and coilovers) and the frame? I'm assuming I may have to have Addco, or someone, custom build one, but I'm just hoping someone has had a similar situation and can give direction. I should also add, that id like to accomplish this without welding...just drilling, if possible. Thanks, Josh





 

Don Jacks

Well Seasoned Member
Supporting Member 3
With the right spring/shock combo on this set up,as it is now,a sway bar would be an unnecessary addition. I mean this isn't going to be an auto cross or road race set up is it?
 

Dicey58

Well Known Member
Supporting Member 1
With the right spring/shock combo on this set up,as it is now,a sway bar would be an unnecessary addition. I mean this isn't going to be an auto cross or road race set up is it?
No racing of any kind, Don. I plan on an 1.25 up front and thought maybe a 3/4 to 7/8 in the rear would compliment. It's just such a heavy car I thought I would need both, and I am putting a fair amount of effort into the chassis to get it to handle as well as possible. Would have loved an RS or AM chassis, but I've done the best with my budget...just don't want to skip something that would make all the changes for naught. What would I need for a spring sans a rear sway? Would it need to be a heavier spring? What would be right? I am putting Viking double adjustables all around. Thanks for the reply, Don, if you could expound I'd love to hear it!

Josh
 

Don Jacks

Well Seasoned Member
Supporting Member 3
Josh,I could be off a little here,but I'd go no more than 5-10 percent heavier on the factory spring rate when using these shocks.The factory rates were set up for a softer,more comfortable ride,and you're going more toward "performance" handling. Basicly the spring is to support the car,and you can "tune" the shock to get most,if not all of the handling that you want.I do like your plans regarding the front bar however.
 

Dicey58

Well Known Member
Supporting Member 1
Josh,I could be off a little here,but I'd go no more than 5-10 percent heavier on the factory spring rate when using these shocks.The factory rates were set up for a softer,more comfortable ride,and you're going more toward "performance" handling. Basicly the spring is to support the car,and you can "tune" the shock to get most,if not all of the handling that you want.
Don, 5-10% makes sense to me, as I would like a bit more firmness in support, but not a lumber wagon. Rebound and compression would handle the rest. I'm still unsure how this would lessen my need for a sway bar, as I thought it is another dynamic all altogether within the chassis? Sorry for the questions, I just like to understand things
 

Don Jacks

Well Seasoned Member
Supporting Member 3
OK,The way I'm seeing it,and this is just my opinion,is that with the design of this system coupled with the stiffer,stronger tubular control arms,and the "poly" bushings,and the wider ,taller tires,is going to tighten up any sway that would otherwise be in this car.Adding a rear bar will only make things stiffer,and could lead to an oversteer[loose] condition in the rear of the car. A lot will depend also on the type of tire that you use.A wide tire with a decent sidewall will provide a better overall ride than these modern,tall ,thin sidewall stuff that some people seem to favor today.That and they just don't look like they belong on one of these classic older cars.Add that to the fact that while these no sidewall tires will corner better,but don't hook for sh@t in a straight line,and I just wouldn't do it.
 

61BUBBLE348

Well Known Member
Supporting Member 11
I was of the belief that with sway bars, particularly on the rear, that if you increase the size of the sway bar on the front you should decrease the size of the sway bar on the rear.

I have built a couple of hot rods over the years using parallel 4 bar with panhard bar and utilising Jag coil overs 1 either side, never worried about the rear sway bars as the stiffness and inherent binding of the components tends to be enough as Don has stated. Both these cars rode and handled very well.

In relation to spring rates, on say a 2400 lb roadster I used 220 lb coil springs with my 38 the cars weighs around 3000 lb and I have 330 lb springs. How this rates for a full size Chev I am not sure but at least it gives you a starting point.
There are some good books about modified suspensions for drag racing that give you the ability to mathematically calculate the spring rates.

By the way I like what you have done with your 58.
Best of luck with your build
 

Dicey58

Well Known Member
Supporting Member 1
OK,The way I'm seeing it,and this is just my opinion,is that with the design of this system coupled with the stiffer,stronger tubular control arms,and the "poly" bushings,and the wider ,taller tires,is going to tighten up any sway that would otherwise be in this car.Adding a rear bar will only make things stiffer,and could lead to an oversteer[loose] condition in the rear of the car. A lot will depend also on the type of tire that you use.A wide tire with a decent sidewall will provide a better overall ride than these modern,tall ,thin sidewall stuff that some people seem to favor today.That and they just don't look like they belong on one of these classic older cars.Add that to the fact that while these no sidewall tires will corner better,but don't hook for sh@t in a straight line,and I just wouldn't do it.
I'm tracking with what your saying, Don. You're not going to like my tire choice, as they're 13.6" wide, but only 4.2" of sidewall. ;) They're not rubber bands in my opinion, but they don't have a tall sidewall either. Thank you for taking the time to reply.
 

Dicey58

Well Known Member
Supporting Member 1
I was of the belief that with sway bars, particularly on the rear, that if you increase the size of the sway bar on the front you should decrease the size of the sway bar on the rear.

I have built a couple of hot rods over the years using parallel 4 bar with panhard bar and utilising Jag coil overs 1 either side, never worried about the rear sway bars as the stiffness and inherent binding of the components tends to be enough as Don has stated. Both these cars rode and handled very well.

In relation to spring rates, on say a 2400 lb roadster I used 220 lb coil springs with my 38 the cars weighs around 3000 lb and I have 330 lb springs. How this rates for a full size Chev I am not sure but at least it gives you a starting point.
There are some good books about modified suspensions for drag racing that give you the ability to mathematically calculate the spring rates.

By the way I like what you have done with your 58.
Best of luck with your build
Thank you for the compliment 61. For spring rates I should probably just call Viking and see what they have to say for this set up. As for the sway bar issue and having the big one up front, I thought no bigger than 3/4 or 7/8 would be needed...I like the idea of not needing one at all even better.
 

models916

Well Known Member
Supporting Member 7
Why only single adjustable upper control arms? Makes for a real pain in the assss.
 

Dicey58

Well Known Member
Supporting Member 1
Why only single adjustable upper control arms? Makes for a real pain in the assss.
I'd have to ask the guy who ordered it and did the set up, but I would have to take the blame on that one as I didn't specify....one of the many things I'll have overlooked as this project goes on I'm sure.:D I believe he said he has adjusted it to where it needs to be, so I'm not too concerned. Of course adjustments may need to be made, but hopefully only one more time.
 

Dicey58

Well Known Member
Supporting Member 1
Thanks Boxerdog! I remember looking at this website about year ago before work began on the car and forgot about them. Could be a great option...I will call them today.
Josh
 

Dicey58

Well Known Member
Supporting Member 1
Addco responded within 36 hours of my email asking for their opinion a rear sway bar. I've never delt with them, but I'm impressed. They thought the set up was unique enough that they advised I should run it without a bar and it may be fine. If I don't like it, then at least there will be a baseline to work off of. That's another thing that impressed me...they didn't just try and sell me something and they put some thought into their response.

Josh
 

models916

Well Known Member
Supporting Member 7
That does not make sense to me. Are you talking SWAY bar or TRACK bar. Track bar locates the rear and keeps it from moving around and the sway bar keeps the body from leaning. Why would just having a unique 4 link be sufficient for not having a sway bar?
 

boxerdog

Well Known Member
Supporting Member 5
I think it all depends what you want to accomplish. Some 4-link designs, and leaf spring cars in general, resist body roll because of their built-in geometry and/or bushings.
Some circle track cars don't "like" rear sway bars and are more adjustable and handle better if all of the anti-roll takes place in the front.
OTOH, a small rear bar and an oversized front bar can be a great combination...for some uses, not all. A track car is a much different beast from a drag car, etc. JMO.
 

Dicey58

Well Known Member
Supporting Member 1
That's what I was thinking initially upon reading their response. But I just think there are so many variables they just think it better for me to start from zero. Above my pay grade to be sure.
That does not make sense to me. Are you talking SWAY bar or TRACK bar. Track bar locates the rear and keeps it from moving around and the sway bar keeps the body from leaning. Why would just having a unique 4 link be sufficient for not having a sway bar?
 

hotrodpete

Member
This may involve welding but... Check out the site called Welder series . Paul has a lot of cool stuff that can be used in any chassis. I used them since 1985 and they are still great to deal with. They have a lot advice and common sense approaches to problems.
You may be able to weld a mounting plate and bolt this in also??
 
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