best all around a-arms and balls 4 a 70-72 A body

Discussion in 'Pro-Touring' started by agetnt9, May 17, 2016.

  1. agetnt9

    agetnt9 Agetnt9 (Dan)

    So i have been on the net for days and days.
    There are .5 and .9 upper balls
    There are tubular with better caster built in
    There are some upper arms that are flater that others and almost a must to use the tall ball of .9 for clearance of frame i think.

    Sooooo,, ((( Do ya think that a stock lower arm with a good standard ball or a .5 taller one would be best with a cheaper tubular upper

    with the good .9 tall ball with Delrin bushings ???????? )))

    Also there are Delrin greasable bushings, and rubber, and del-a-lum, and alluminum, and poly... Wow And some are very pricy..

    Juat want to get this right the first time Thanx :)
  2. SCamaroSS2000

    SCamaroSS2000 Well-Known Member

    I don'the know what is best but I am going to go with SC and C upper and lower control arms. I will get the taller ball joints using the stock spindles
    first. Down the road I will use stock ball joint size and use the afs spindles. I can then mount corvette brakes easily and save 400 or so from Kore 3s package. The 400 plus savings offset the spindle cost slightly. The SC and C upper a arms allow the most versatility of all the a arms. The others have more of a stock look with built in caster so you just put them in and are ready to go. SC and C arms can be adjusted as needed for ever.

    I have researched a ton and would say this route is best for a cruiser that handles. It would be totally track ready too but I doubt I will do that with the car. I just want it to handle because I live in an area with lots of mountain and twisties that lead to the beach. I like the adjustability option.
  3. Stg'd 2Discover

    Stg'd 2Discover Lumpty, Lumpty, Lumpty

    Give Ramey, the engineer at UMI, a call for advice. He may be able to steer you in the direction of what you want to use the car for.
    With a stock spindle setup I went with Viking coilovers, UMI's upper and lower kit with delrin and a 1/2" taller upper only ball joint. UMI use quality ball joints as opposed to some offshore products that are dangereous.
  4. agetnt9

    agetnt9 Agetnt9 (Dan)

    Thats what i was thinking UMI with .5 taller ball . But if .5 is good is .9 better ? also looks like .9 only comes with the adj. arms and ball ends.

    I would think that would be too ridgid and where out fairly fast.

    Thanx for any insight on this. I have asked threw the web UMI suport and got good response but soooo much $ like to hear it from someone that drives a car around and down da track the ins and outs of .5 and .9 balls
    Darron72Skylark likes this.
  5. SCamaroSS2000

    SCamaroSS2000 Well-Known Member

    When I spoke with UMI they thought the 0.5 inch taller upper ball joint provides probably most will ever need for a cruiser. I have no real world expereince with their various ball joing size options though. Realistically you will not go wrong with the big vendor'so setups. I like the idea of going with the afs spindle down the road though so I am opting to go with SC and C a arms and the tall Howe ball joints that can be changed with the taller pin to a shorter pin when changing spindles.
  6. LARRY70GS

    LARRY70GS a.k.a. "THE WIZARD"

    What exactly are you trying to accomplish? That will, in part, dictate the parts you buy. One really effective way to make an A Body handle is to change the camber gain when the car corners. In a stock A body, as the front suspension compresses, the camber goes +, the top of the tire tilts out, and the tire slip increases, causing under steer. To make the car handle better, you want the opposite. You want the camber to go -. That causes the tire to stand up straighter in a turn and the front end goes where it is steered.

    Back in the 80's, I used a kit from HO Enterprises to fit an F body spindle into my 72 Skylark. The F body spindle is taller, and altered the camber gain to -. It made a huge difference in the handling. From what I understand, taller ball joints do the same thing. Someone correct me if I am wrong, but seems to me taller is better.

    Tubular control arms are stronger and lighter, both good things. Stiffer bushings deflect less, a good thing, but they can also increase ride harshness. So what do you want, and what can you live with?

    I would think you get what you pay for as far as quality is concerned.
  7. hugger

    hugger Well-Known Member

    Global West makes the best street duty stuff IMO, there stuff is heavy but will handle our heavy cars and all these crappy roads with ease
  8. TimR

    TimR Nutcase at large

    I installed UMI upper arms with 0.90 ball joints on my hardtop. Did the alignment myself (going to check #'s with prof shop later on but couldn't wait). Those were the only mods, everything else on car stock except 1 1/8" front swaybar, and with new alignment and arms I have to say it did make a fair difference. I can just drive into corners and load it up with no issues, returns better, tires are not rolling over like they used to. Keep in mind I have owned this car a long long time (30 years ....OMG I'm getting old!!) so I know it well. I had to call UMI about a small issue (not product related) and I have to say the service was exceptional. Nobody laughed at me :)

    BTW these arms were 3lbs lighter than stock (each, total of 6lbs) if anyone cares.

    I ordered the .9 tallers without discussing with anyone, lots of reading though. No regrets. I will say buy quality, your wheels and your life will be hanging on these things, you don't want a failure!!
    Darron72Skylark likes this.
  9. agetnt9

    agetnt9 Agetnt9 (Dan)

    After many many hours of comparing parts...... I think that Global West with a .5 or a .9 upper A arm is the best there is. lower arm with coil over also,,,, But WOW!!:shock: thats alot of :dollar: !!!

    As for the rear, I just need to beat my brothers 71 Nova in a straight line and maybe a little around the house. those Roto joints by UMI i think you would have to have all 8 ends to make it work right, just 2 or 4 would put alot
    of stress on the ends with poly or rubber i would think. Not sure on that.. Does anyone have those ?
  10. Kevmurray

    Kevmurray Well-Known Member

    I have been down the path you are on and I think this is what you wanted to hear. Sorry it's a bit long winded, I tried to shorten it. I initially set out to fix the notoriously poor GM a-body front suspension and give the rear some help (though it isn't too bad if you're not drag racing). Bottom line is start with a plan so you dont run into "upgrade dead ends".

    I dropped the car with UMI 1" springs (4050 kit) and installed bilstein shocks.

    I stretched the spindles with Proforged 0.9" ubj and 0.5" lbj. They are cheaper than Howe but not rebuildable. The taller lower ball joint also fixes the factory bump steer by raising the steering arm.

    Before I really knew what I was doing I purchased a set of the ebay a-arms. I now understand they are Global West knock-offs. They actually weren't that bad but I may have been lucky. I ended up replacing them for two reasons. The first was a design(copy?) flaw where all the castor gain was acheived by moving the upper ball joint back. This resulted in the tire almost rubbing the rear of the wheel well. The second was they were not intended to be used with a tall (or stretched) spindle and so couldn't keep up with my other mods (dead end). I purchased BMR replacements because they split the castor gain between the upper and lower arms which keeps the wheel centered. I have delrin bushings and dont mind the NVH.

    For the rear control arms I went with Spohn because they were cheaper and on sale to boot. They also delete the factory sway bar mounts which makes them nice and clean. Later I added UMI sperical joints to the axle ears so the rear end now articulates like a stripper. All 8 joints are delrin spherical and all 4 arms are double adjustable. Wheel hop is gone.

    For sway bars I used Helwig and I'm very happy with them. 1.25" in front and 1.125" in the rear.The factory rear sway bar mounted to the trailing arms which is crap. The Helwig is frame-referenced and adjustable.

    I probably left something out but if you have questions let me know.
  11. agetnt9

    agetnt9 Agetnt9 (Dan)

    Thanx for the info on this...... Would U have the part # on da arms? i can't seem to find anything that says the lower arm ball is moved forward.
    Also what is NVH ? (I have delrin bushings and dont mind the NVH.)
    Is delrin and del-a-lum about the same thing?

    I feel retarded today for some reason , ha
  12. agetnt9

    agetnt9 Agetnt9 (Dan)

    Also, wouldn't you have to use all 8 spherical joints in the rear to move freely? seems to me that if you use just 4 it would put more bind on the other 4. All or nothing? It
    seem that it would try to twist the poly bushings, or not :Do No: Or just all poly and good sway bar would keep car more flat:Do No:
  13. Kevmurray

    Kevmurray Well-Known Member

    Part Number is AA033 and I bought the grade 8 fasteners too as the factory stuff is usually seized and needs to be cut off. Better to have the grade 8 stuff than even bother to try and salvage the aging factory ones anyway. As for the castor split between the upper and lower arms I read it somewhere on the BMR site. I believe they said something like "2 degree caster increase" for the lower arms and same for uppers. Later I was talking to one of their reps, "TC" I believe his name was, and he confirmed it.

    NVH stands for noise, vibration and harshness. It's a term used in engineering, I swear I didn't make it up lol.

    Del-a-lum is a combination of delrin and aluminum and is basically the same thing. Since we're talking about delrin I'll mention that there are two types: a cheap one used often by machinists for non-structural stuff because it's cheap and machines nicely, the other is much more expensive but contains teflon which is great for bushings because they are self-lubricating. If you buy from a reputable vendor you don't have to worry about which you end up with. It's part of the cost of the pricier arms.

    edit: I realized when I said Del-a-lum is a combination of delrin and aluminum that I may have been unclear. The outer sleaves are aluminum to keep weight down and the anti-friction bushing is made of delrin. Here is a good photo from the Global West site that makes it clear. Note the channels around the center of the white delrin bushings that allows the grease to spread evenly. The center sleaves are steel (yellow iridite finish in the photo) to keep things from being crushed by the bolts.

    Last edited: Jul 21, 2016
  14. Kevmurray

    Kevmurray Well-Known Member

    Absolutely right. Poly alone will just bind because it is high durometer and tubular arms will not absorb any torsion at all. It's a big contributor to sqeaky bushings. There is at least one make that swivels in the center of the arm to eliminate bind with planar bushings.

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