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Just got a ADDCO rear sway bar that fits perfectly on my stock rear control arms that have the holes already drilled out. It did not come with hardware and I know some kits come with spacers to go inbetween the rear lower control arm so it does not crush when the bolts are torqued down.
Did the factory sway bar come with the spacers or am I good to just mount it at 35ft lbs and no spacers? Am I able to just get some grade 8 bolts and nuts and possible spacers from local hardware store that will be good enough?
What are you calling "spacers"? The tubes that go inside the lower control arms or the flat shims with the two notches that go between the bar and the side of the LCA?
Yes, the sleeves/tubes that come with some kits and some don't. UMI kit does not have those tubes but a lot of other brands do. I am trying to figure out if I am required to use the tubes inside the LCA if I have factory arms that were predrilled for a sway bar.
Yes, the sleeves/tubes that come with some kits and some don't. UMI kit does not have those tubes but a lot of other brands do. I am trying to figure out if I am required to use the tubes inside the LCA if I have factory arms that were predrilled for a sway bar.
The factory arms for rear sway bars have the boxing plates that also have features that reinforce the arms where the bolts go. If you are simply bolting the bar to open-section arms (never a great idea), then you need spacers as a minimum. The weld-on boxing plates would be a much better choice. I suspect UMI assumes you will be using this bar with their aftermarket boxed arms anyway, so no need for the spacer tubes.
The factory arms for rear sway bars have the boxing plates that also have features that reinforce the arms where the bolts go. If you are simply bolting the bar to open-section arms (never a great idea), then you need spacers as a minimum. The weld-on boxing plates would be a much better choice. I suspect UMI assumes you will be using this bar with their aftermarket boxed arms anyway, so no need for the spacer tubes.
I had the same idea but I guess what confused me is they have the open section and the sway bar mounting holes. I cant seem to find anyone who sells the tubing that goes inbetween but I can probably find something strong enough to work temporarily until I upgrade the rear suspension.
Last edited by yeahbuddy; February 16th, 2020 at 12:36 PM.
Go to the hardware store and buy a couple of small black pipe nipples that the bolts will slide through. Cut them to length so that they will fit inside the control arm gap snug and install your sway bar.
Spot welds aren't how those are installed. There are a series of 1" long (minimum) full penetration welds on each edge.
You're right. I was a bit over zealous and quick to the draw. They should be penetration welds. I was thinking of answering/addressing the OP's statement with regards to finding tubing and instead wanted to demonstrate they do sell the inserts to fabricate open>box.
Go to the hardware store and buy a couple of small black pipe nipples that the bolts will slide through. Cut them to length so that they will fit inside the control arm gap snug and install your sway bar.
I am going to be going to UMI rear suspension eventually so I really don't want to spend much money or time on this upgrade. Got the sway bar for $50 locally. Took a trip to the hardware store and came up with this. I think this will be good for now. What do you all think?
Grade 8 3/8-16 x 3" bolt with locking nut
Steel spacer 3/8 ID x 1.5 (Cut down to 1.20")
4 washers
It will allow you to install the sway bar - and, that is all it will allow you to do. It will do nothing to increase the stiffness of the rear end, which is what the rear sway bar is designed to accomplish, along with boxed LCAs. Those bolts and spacer provide no stiffness, IMO.
It will allow you to install the sway bar - and, that is all it will allow you to do. It will do nothing to increase the stiffness of the rear end, which is what the rear sway bar is designed to accomplish, along with boxed LCAs. Those bolts and spacer provide no stiffness, IMO.
The specific spacers I went with or spacers in general because literally 90% of the after market sway bar kits come with the similar bolts, spacers and washers with instructions to so as stated.
The specific spacers I went with or spacers in general because literally 90% of the after market sway bar kits come with the similar bolts, spacers and washers with instructions to so as stated.
I understand. The bolts, the spacers and the washers all "fit". With regards to installing a sway bar they will allow you to install a sway bar. The hardware in & of themselves will provide no (or minimal) stiffness to the rear end without boxed LCAs. If that's what you're after, they'll work to install the sway bar. You're probably going to get varying opinions, that's my opinion. I wouldn't install a rear sway bar unless I had boxed rear LCAs to install the sway bar.
I understand. The bolts, the spacers and the washers all "fit". With regards to installing a sway bar they will allow you to install a sway bar. The hardware in & of themselves will provide no (or minimal) stiffness to the rear end without boxed LCAs. If that's what you're after, they'll work to install the sway bar. You're probably going to get varying opinions, that's my opinion. I wouldn't install a rear sway bar unless I had boxed rear LCAs to install the sway bar.
The reviews tell a different story but I will find out myself eventually. It may not end up being as stiff as boxed LCA but I think it will definitely add some. Time will tell.
Actually, it will allow the sway bar to work. I would go with the UMI lowers when you can afford to do so as the stock lower arms may stress with just the spacers and eventually crack.
Actually, it will allow the sway bar to work. I would go with the UMI lowers when you can afford to do so as the stock lower arms may stress with just the spacers and eventually crack.
That's the plan. It will probably be like that for a few months before I change it out. Working my way from the front to the rear but happen to stumble across a good deal so I picked it up.
That's the plan. It will probably be like that for a few months before I change it out. Working my way from the front to the rear but happen to stumble across a good deal so I picked it up.
That's how you eat an elephant, one bite at a time. Nice score
Actually, it will allow the sway bar to work. I would go with the UMI lowers when you can afford to do so as the stock lower arms may stress with just the spacers and eventually crack.
I disagree. It will not allow the sway bar to work. It will allow the sway bar to attach to the open LCAs. The sway bar is a torsion spring. The design of which is to stiffen the rear-end so both sides of the rear suspension (LH & RH) no longer operate independently of each other. In a normal corner, one side of the rear end will compress the suspension and the other (opposing side) will de-compress the suspension (lift). Again, the sway bar is designed to stiffen the rear-end suspension so as to overcome the de-compression on the opposing side. The sway bar stiffens the rear suspension so the opposing side decompression is reduced (reducing the tendency of the opposing side of the rear suspension to lift). With open LCAs there is no gain, IMO. The two bolts provide no ability to maintain stiffness and provide negligible (if any) benefit for a vehicle which under- steers like a marshmallow. If you're looking to eat an elephant, it's a minimal first bite. But, you won't gain anything until you box the LCAs.
I disagree. It will not allow the sway bar to work. It will allow the sway bar to attach to the open LCAs. The sway bar is a torsion spring. The design of which is to stiffen the rear-end so both sides of the rear suspension (LH & RH) no longer operate independently of each other. In a normal corner, one side of the rear end will compress the suspension and the other (opposing side) will de-compress the suspension (lift). Again, the sway bar is designed to stiffen the rear-end suspension so as to overcome the de-compression on the opposing side. The sway bar stiffens the rear suspension so the opposing side decompression is reduced (reducing the tendency of the opposing side of the rear suspension to lift). With open LCAs there is no gain, IMO. The two bolts provide no ability to maintain stiffness and provide negligible (if any) benefit for a vehicle which under- steers like a marshmallow. If you're looking to eat an elephant, it's a minimal first bite. But, you won't gain anything until you box the LCAs.
I got a better idea. How about I record a before and after video and we see if it actually did make a difference. Won't be for a couple weeks but I will post it on here once I do. I need to empty the parts out my back seat first so it don't go flying everywhere.
I got a better idea. How about I record a before and after video and we see if it actually did make a difference. Won't be for a couple weeks but I will post it on here once I do. I need to empty the parts out my back seat first so it don't go flying everywhere.
You're going to get differences of opinions. One of the benefits of a forum is to seek advice. In the end it's your decision based upon the advice you receive and the direction you pursue. Bear this in mind - there is a very specific reason they employ boxed rear LCAs.
You're going to get differences of opinions. One of the benefits of a forum is to seek advice. In the end it's your decision based upon the advice you receive and the direction you pursue. Bear this in mind - there is a very specific reason they employ boxed rear LCAs.
I agree with what you are saying and I come on here and ask questions for that reason. That being said, my reasoning has come down to if there are over 5 major brands out there manufacturing a sway bar and they include spacers with the detailed instructions of using it in that form, I have trust that they are not going to instruct their customer to do something that is going to be ineffective or unsafe/being a liability. Boxed LCA are the obvious better way to go and will be alot more rigid but I believe this will be good enough until that happens later this year.
Time will tell when I install it and drive the car. I will still record a before and after for the fun of it though.
Last edited by yeahbuddy; February 16th, 2020 at 07:54 PM.
Whichever you might choose, check the prices on Amazon. Most often Amazon will have free shipping on orders over $25.00. Of course, free shipping if you're Prime. Also, check the prices on UMI Performance. I believe they have free shipping on orders over $200.00
At any rate, check on shipping prices when you decide on a purchase.
I have a 68 Cutlass Holiday Sedan and it just got a new Wilwood front disc conversion, complete steering built w/ MOOG parts, quick ratio gearbox, 17" 2 piece wheels w/ 275/40 all around installed in the last couple months.
Have CPP tubular control arms upper/lower, Proforged tall upper ball joint, QA1 adjustable front shock, rebuilt TH350 w/ shift kit, Hurst Quarter Stick, and the rear sway bar waiting to go on. Working my way towards the rear where a locker sounds fun.
The car has the name....and its called "WHY" Will post pics once its done.
Nice setup. I was wondering what vehicle was going to be the recipient of the rear sway bar. Look forward to pics.
Thanks. In 2015 I made a thread on here called "Help me make my 68 Cutlass Supreme fun to drive". I am not sure what got into me but I woke up a couple months ago and started knocking out everything that was suggested on that thread by other users, especially MDchanic. That and being really lucky finding some insane deals online has made it possible. I am going to update that thread soon once I get everything installed. Its already looking and feeling like a different car.
That's the same as what I just put on my car, very easy to install. So far I'm enjoying the locker too. There are a great many Chevelles running around with the 2 spacers and sway bars installed in stock unboxed control arms. It'll be fine until you get a some boxed or tubular replacements. Update your thread its been 5 years.
That's the same as what I just put on my car, very easy to install. So far I'm enjoying the locker too. There are a great many Chevelles running around with the 2 spacers and sway bars installed in stock unboxed control arms. It'll be fine until you get a some boxed or tubular replacements. Update your thread its been 5 years.
It looks fairly simple. Did you purchase the control arm braces from them? I am wondering if that helps much.
I disagree. It will not allow the sway bar to work. It will allow the sway bar to attach to the open LCAs. The sway bar is a torsion spring. The design of which is to stiffen the rear-end so both sides of the rear suspension (LH & RH) no longer operate independently of each other. In a normal corner, one side of the rear end will compress the suspension and the other (opposing side) will de-compress the suspension (lift). Again, the sway bar is designed to stiffen the rear-end suspension so as to overcome the de-compression on the opposing side. The sway bar stiffens the rear suspension so the opposing side decompression is reduced (reducing the tendency of the opposing side of the rear suspension to lift). With open LCAs there is no gain, IMO. The two bolts provide no ability to maintain stiffness and provide negligible (if any) benefit for a vehicle which under- steers like a marshmallow. If you're looking to eat an elephant, it's a minimal first bite. But, you won't gain anything until you box the LCAs.
I disagree that using a sway bar w/ an un-boxed rear LCAs provide no benefit. As you correctly state, the sway bar acts as a torsional spring, which ties the up & down motion of the LCAs together by applying a force to the LCAs through the two bolts on each arm, which are positioned in a plane that is (roughly) normal to the axis of torsion of the sway bar. The LCAs can't help but want to act together (up & down) through the sway bar and reduce the amount of body roll in a corner. While the un-boxed LCAs will flex (out of plane) and twist more than boxed LCAs as a result of side-to-side forces during cornering reducing the effectiveness of the sway bar (and possibly result in life-reducing stress cracking), it does not reduce the sway bar's effectiveness to zero. I've been down this same road before, using spacers in my original un-boxed LCAs and then later upgrading the LCAs to SSM lift bars, and I definitely noticed less body roll w/ the rear sway / un-boxed LCAs than without the sway bar. I'd say that between a no sway bar w/ un-boxed LCAs and a sway bar w/ boxed SSM lift bars, the un-boxed LCA / sway bar combination resulted in ~80% of the effectiveness of a proper boxed LCA + sway bar combination. Definitely worth it IMO.
Last edited by JohnnyBs68S; February 17th, 2020 at 04:52 AM.
The reviews tell a different story but I will find out myself eventually. It may not end up being as stiff as boxed LCA but I think it will definitely add some. Time will tell.
It should make a noticeable difference and the price was right.
February 16th, 2020, 11:38 AM
At least it can go on properly. Thanks for the help as usual.
Will post pics once its done.
