If you're just a cruiser, why do you want any of it? Those kits are expensive!

I installed adjustable uppers because I installed a T-56 trans and needed to adjust my driveline angles. I installed a pro-touring anti-roll bar and boxed my lower arms. I also installed rear control arm braces because the stock ones were not in good shape. I changed to all poly bushings, also. I'm over 600 hp, so I thought that I needed to stiffen things up a bit for the more spirited driving.

I put on a heavier front sway bar, and it handles pretty decent. I have problems with high speed wandering, but that is mostly related to the front suspension...I think...

Mark

 

If you're just a cruiser, why do you want any of it? Those kits are expensive!

I agree, The main reason for the adjustable uppers is IF you want/need to set the pinion angle... This can be important for lowered cars , and maybe drag racers (but not sure how much need for coil spring cars)...

IMO, I'd avoid poly bushings in the upper arms, especially "boxed" or stiff upper arms... Look at the rear suspension, note the different angles of the control arms and try to picture how these move when you hit a bump, and you can see that the rear arms/bushing NEED to flex in order for the rear axle to articulate. Not enough flex in the arms and bushing makes the rear suspension too stiff (those binding arms will act like an additional very stiff spring). Ever notice how difficult it is to get that last arm into position and the last bolt thru the upper arms and frame? You have to get the rearend in just the right position. I once swapped poly bushed stock arms for rubber bushing (just the uppers), and the ride and handling both improved... I am running upper arms with a spherical joint at the frame-side, and new rubber bushing in the axle housing (next time I'll go to spherical there too)...

If the arms and bushings can't deflect, then the stress goes elsewhere... usually into the frame cross-member. Ever notice that the Big Block, hipo 4-speeds, etc use those extra reinforcement braces? Those help transfer some of the stress from the frame cross-member to the lower bolt and the much stronger area of the frame... Maybe frames have a tendency to crack that upper cross-member, so why risk that with stiff upper arms?

For a cruiser, even with some spirited driving, new, quality rubber bushings will work great, along with shocks and maybe a rear swaybar...


Poly bushings and boxed lower arms aren't as bad, because they are roughly parallel, not as much bind...

...I put on a heavier front sway bar, and it handles pretty decent. I have problems with high speed wandering, but that is mostly related to the front suspension...I think...

Mark

Mark, is all your steering linkage fresh and/or tight? Was all the suspension fasteners torqued to spec? Did you change the steering box? How about alignment specs? These cars were designed and built before radial tires, I have heard that revised alignment specs (even when using stock parts) can help with handling...

Another thing to consider, is a "firmer" steering box... Not necessarily a Quick ratio, but rather a larger input T-bar ( but these are usually used only on the quick ratio boxes)...

My Chevelle, I once had a high-speed floaty issue right after updating... Turns out I didn't torque all the bolts. I tightened everything, but I was using those aircraft nylon lock-nuts, so I thought it would be fine... Went back and torqued all the bolts (I think 85+ lb-ft), and a huge difference... Turns out the frame brackets actually deflect and pinch the inner bushing sleeves...

Another change for me was the install of a firm box (AGR) in place of a used GM quick ratio box... Same ratio, but the firmer valving made a HUGE difference in road feel...

Another option since it is just a cruiser is to just replace your bushings with factory rubber, drill your arms for sway bar mounting (there should be locating dimples already there) and don't worry with the boxing. Pick up a used sway bar or the cheapest new you can find.

I have done this... Without the boxing or a sleeve around the bolts the arms will start to collapse, which may cause them to bend and deflect when the swaybar bolts are torqued... Should be okay if you don't go crazy with the bolt torque...

I took my stock lowers, and welded a 3/16" plate along the bottom, but you could also cut some spacers out of pipe, etc...

 

I would have to agree...money better spent elsewhere.

 

Mike, The short answer is they are adjustable to allow changes in drive line angle just as Mark said. If you are unfamiliar with your suspension or would like to make educated choices on improvements I would suggest the book in the link below. Can get a revised edition for $26.00 or an original version for $22.00. It explains what your A body suspension is, options to improve it, and different choices for improvements. I would recommend it. For 20 plus dollars it may prevent you from making choices you may regret.

How to Make Your Muscle Car Handle: Revised Edition: Mark Savitske: 9781613251751: Amazon.com: Books

 

Thanks for the feedback guys! I was thinking of doing this because I wanted to add a sway bar, my bushings are shot, car has 2" drop springs and didn't know if driveline angle was an issue cuz i have minor vibration issues. Also heard horror stories of the stamped units twisting and breaking, want to tighten things up a bit and for peace of mind since the OE stuff is almost 50 years old.
I did a big sway bar up front last summer and love it. Is there another way I can tighten things up a bit. I'm all ears and don't want to waste money for sure

 

https://www.opgi.com/el-camino/KR00445/

Just replace the bushings in your uppers.

 

When I took my UCA's off, one of the bushings fell out. Another reason I went to adjustable UCA's. I don't really think they would break unless severely rusted. I got my adjustable UCA's and trailing arm braces from PMT Fabrication.

Lower control arm reinforcement kits are cheap ~$30, but have to be welded in. Like Rich said, just change the bushings. The upper bushings on the differential are a pain, but doable. They would have to be changed anyway regardless of replacement UCA.

 

I linked the lower control arms above assuming your arms did not have provisions for a sway bar mount. If they do your arms could easily be boxed while out for bushing replacement.

 

Mike: I can tell you this much about rear sway bars. Many of them mount to the rear control arms. According to information I obtained from the book in my other link, when done in that fashion they bind up your control arms. There are sway bars that mount in other ways besides attaching to the control arms. UMI sells one that attaches in another fashion as does Hellwig. As far as your original equipment. You could box in your original rear control arms your self and just change bushings in upper and lower control arms. That would be the least expensive way to go. If you decide to go that route you might need some new hardware. Most of the time the hardware is pretty corroded.

 

Thanks for talking me off the ledge guys. I'll look into bushings and simply boxing the lowers since that's pretty inexpensive to do. Then take her for a ride and see if i feel like i need a little more roll control.

 

Then take her for a ride and see if i feel like i need a little more roll control.

If you want roll control, look at a Hellwig Pro-touring anti-roll bar. New Pro Touring Sway Bars | Hellwig Products Relatively inexpensive. $261 at Amazon. You don't need a $400 drag bar for a street car.

 

Are your arms bushed for a sway bar already? The pluses outweigh the minuses with a rear sway bar even when connected to the control arms.

 

no, mine are just the open stamped units with no holes for sway bar hardware

Mike even thou you are only cruzin with your car now
you never know what is going to happen in the future or right down the road !

If you need to swerve to avoid a accident you will have better control with not only a good/well made sway bar
but good quality Rear Control Arms are a must and UMI Perf makes them
and as others above have said there are good reasons for adjustables plus boxed lowers .

I have bought all my car's new suspension parts from UMI Perf .

I have bought various suspension kits from UMI Perf
and they are the most quality built parts I have ever seen or used .
1964-1967 GM A-Body Rear Control Arm Kit, Fully Boxed Lowers, Adjustable Uppers [402126] - $539.99 : UMI Performance, Inc.

1964 - 1972 GM A-Body 1 Solid Chromoly Rear Sway Bar [4034] - $159.99 : UMI Performance, Inc.

64-72 GM A-Body Tubular Upper & Lower Front A-Arm Kit [403133] - $1,099.99 : UMI Performance, Inc.

Yeah, exactly what started this all. Someone pulling out in front of me and having to swerve out of the way, experiencing a ton of body roll.

But that's the thing, you start buying items separatly, then you're not too far away from buying a whole kit and replacing everything. That pro touring swaybar and new bushing are gona be around $300, and you're half way there to a whole kit from PMT

1965 1967 Chevelle SS GTO Le Mans Cutlass Skylark Rear Control Trailing Arms | eBay

 

I agree with Mark. That's a good sway bar. I couldn't decide between the Hellwig and UMI's version of that bar. Ended up with the UMI. Probably would have been as happy with the Hellwig. Both nice pieces.

 

The adjustable uppers also help if your rear end needs a little. Nudge to get centered if running wide tires.

 

Mike even thou you are only cruzin with your car now
you never know what is going to happen in the future or right down the road !

If you need to swerve to avoid a accident you will have better control with not only a good/well made sway bar
but good quality Rear Control Arms are a must and UMI Perf makes them
and as others above have said there are good reasons for adjustables plus boxed lowers .

I have bought all my car's new suspension parts from UMI Perf .

I have bought various suspension kits from UMI Perf
and they are the most quality built parts I have ever seen or used .
1964-1967 GM A-Body Rear Control Arm Kit, Fully Boxed Lowers, Adjustable Uppers [402126] - $539.99 : UMI Performance, Inc.

1964 - 1972 GM A-Body 1 Solid Chromoly Rear Sway Bar [4034] - $159.99 : UMI Performance, Inc.

64-72 GM A-Body Tubular Upper & Lower Front A-Arm Kit [403133] - $1,099.99 : UMI Performance, Inc.

 

Not sure where they're made, based in Indiana and only says 'not made in china'

I think for now I'm going to focus on the UMI and Hellwig touring sway bars. I have a UMI bar up front with their billet mounts, so probably stay consistent and put one in the rear. That might be a good start.

Thanks a lot guys!

 

Which two kits.are you referring to?

 

Mark is correct. Pay attention to your axle tube diameter. There are.at least.3 different possibilities within about 1/4 inch of each other. This is needed to get the the right sized U bolts to attach the bar to the axle. I believe the sway bar in the.PMT kit is.the type that mounts to the control arms.

 

Another option since it is just a cruiser is to just replace your bushings with factory rubber, drill your arms for sway bar mounting (there should be locating dimples already there) and don't worry with the boxing. Pick up a used sway bar or the cheapest new you can find.

 

Boxing the LCA is easy with some flat plate. I did it to mine and them sold them when I got a full Currie set for the rear. I had a sway bar that bolted between the LCA's but sold it with the arms. Now I have a full Helwig set up and it works like a charm. Shocks and springs are important as well. I read Mark's book and had several conversations with him and found his recommendations on suspension to be the real deal. He helped me to figure out what worked without me feeling like he wanted to sell me something. My parts come from several different sources but all compliment each other. You don't need a super stiff suspension to have a great handling car.

 

Well Tony, the front suspension has all new poly bushings, steering linkage, and Billstein shocks. I'm suspecting steering box, but have to decide what to do as far as rebuild or replace.

 

I have most of the suspension and handling books out there
including some very good technical papers.

The one thing that I've found lacking in all of them
was a what to change or adjust and where and
what will be the result?

I found this to be a helpful guide especially if you
are considering pro touring.

If not, it's still a great read for anyone interested
in wanting to know how to adjust their suspension.

Here is a link: LINK

 

I don't think anybody from PMT logs on here and helps with stuff that comes up. UMI does and even helps guys who bought elsewhere. PMT? not so much.

I wouldn't try that deal with bolting the bar to the lower arms without welding in the inserts the stiffen the arms and keep the bolts from collapsing the arm. I've fixed a couple of these over the years, without the insert the bolts can't be tightened enough. You end up with the holes in the arms egged out and the arms trashed. One guy had a brilliant solution, his arms had the holes all wallered out, he welded washers on to fix the holes did the same thing again. Ooof.

 

Ridetech recently did just that Tom... http://www.chevelles.com/forums/61-sponsors/861849-ridetech-street-grip-install-happening-now.html I too would have slid some type of bushings between for piece of mind.