[ZeGermanHam]

Originally Posted by Scarebird

The AFX spindle is the best solution if wheel size and cost is no issue.

In my business I have found there are a lot of people who want to maintain a stock external appearance - it is the niche we fill. For this market the tall ball joint/tube upper works extremely well (I have the Savitske Stage II setup on my Lemans).

Agree with this sentiment. A large number of us, probably most, do not want to be forced into running large diameter wheels to fit the Corvette brakes the AFX spindles typically use. The pro-touring look is not for everyone.

[ponjohn]

Does the tall ball joint option provide more front end travel?

[PontiacMatt72]

My understanding - the tall ball joint helps improve suspension geometry by acting like an extension of the spindle, improving angles between the upper and lower control arms. But, maybe I’m way off.

It’s hard to make myself spend $1300 on AFX spindles. Then I’d have to buy the corresponding control arms. Then the brakes. Shocks and springs next I guess? Ironically, I’m already looking into buying 18” wheels… and was considering lowering the car an inch or 2, so shocks and springs were already on the shopping list. But I JUST bought a set of Global West upper arms, which couldn’t be used with the AFX spindle. Argh. Decisions.

[HWYSTR455]

The upper GW arms can be used with the AFX spindles, not sure why you thought no. There are 2 arms GW offers, either with or without the offset shaft, then you have bushing options. If by chance you need/want a different upper, it is very easy to sell the ones you have, and you can recoup almost the entire cost of whichever you already purchased.

You can buy the knock-off lower control arms, a set is like $300, and you can sell the uppers. Many are getting in the $180-$220 range for just the uppers. There is no geometry advantages built into the lower arms.

Brakes are less expensive than replacing the OE D52 rotors, calipers, and wheel bearings. (Look at the postings I provided). And, down the road, you have many upgrade options if you want to add larger rotors, aftermarket calipers, etc, they bolt right on.

You can hash out the cost, but if you are totaling the $ spent for the upgrade, you are really only about $600 additional cost for the upgrade, which is a total bargain.

Get the GW springs, they are like $150 for the set, and there are a few options on rates/drop. The AFX spindles provide a drop right off the bat, since the location of the pin is slightly higher. (@ 1.25").

If you already have planned on getting 18s, then technically that cost is not a factor. The US Bandits give you a very close to stock-looking arrangement. You can even adapt the OE center caps.

Once you go that route, you will look back and ask yourself why they heck you waited so long to do the upgrade. It is that big of a difference. You will never regret the decision.

You can sell part you have to offset the total cost as well.

Talk to Tobin and Kore3, he can provide multiple options for brakes, as well as providing a rear disc solution.

There is no downside going with this upgrade, period. You will have just about the finest handling config available for the 64-72 A-body. The only way to get better is to buy an aftermarket chassis, and the improvement over the AFX is nominal.

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[JLMounce]

Originally Posted by PontiacMatt72

My understanding - the tall ball joint helps improve suspension geometry by acting like an extension of the spindle, improving angles between the upper and lower control arms. But, maybe I’m way off.

It’s hard to make myself spend $1300 on AFX spindles. Then I’d have to buy the corresponding control arms. Then the brakes. Shocks and springs next I guess? Ironically, I’m already looking into buying 18” wheels… and was considering lowering the car an inch or 2, so shocks and springs were already on the shopping list. But I JUST bought a set of Global West upper arms, which couldn’t be used with the AFX spindle. Argh. Decisions.

If this is your aim, HWY is right and you'll be money ahead to use the AFX knuckle. Especially if you haven't purchased your brakes, shocks, springs and wheels.

I would get everything at the same time, don't try putting something together temporarily to get it on the road. Going that route usually causes issues with mismatched parts.

The AFX spindle height will drop the car, so you don't want to also put a 2" lowering spring in it. The drop spindle height doesn't work against your bump travel, but it does work against your ground clearance.

Decide what brake package you want to run, then order the wheels after you've measured with the brake package installed. a C5 rotor/caliper on the AFX spindle will be closer in hub to hub distance to a drum brake car than it will be to a disk brake car. I also think the c6 Z51 rotor and caliper combination is a really great compromise in cost effectiveness and looks.

[HWYSTR455]

To add a little to comments.

You can't really go by the number of inch drop, too many variables, so any vendor that says '2" drop' or whatever, is only guessing.

On the tubular lower control arms, they use a 'pad' that the spring rides on. There are spacers available to dial your ride height in, so there's always a way to sneak up on the desire ride height.

( https://piratejack.net/1964-1972-che...-shim-spacers/ )

Spring rate can be confusing. NEVER go by 'factory specs', or anything like that, because they are NEVER right. (And I can debate that with anyone that wants to have that conversation on a separate thread or phone call).

One example: You want a free articulating suspension, period. The spring rate gets you to where the weight of the car is controlled within the range of suspension travel. The SHOCK is what dials it all in.

Add to example: OE control arm bushings have 'teeth' in the inner sleeve, and that sleeve is 'captured' in the rubber casting. (must be tightened while car is at ride height). It is used in addition to the spring/shock to provide an overall 'experience'. If you go to a free-articulating bushing, like a solid or poly, you immediately need to add more spring rate.

Most good vendors have a range of travel/rate that thru experience can recommend. Talk to them. Tell them what you expect, and take their' advice. Most will allow at least one spring swap out to get you to where you want. But at like $150 a pair, it's not that critical. Once you you get it dialed to where you like it, you 9 times out of 10 will never change it again.

Personally, I only use, and recommend Global West. Main reason? They use a spring vendor that has tight tolerances. Many 'wire companies' base rates on wire thickness, free height, etc, and allow for a 7-15% tolerance. Think about it. If it's 10%, and you order a 500 lbs spring, that's a 50 lbs swing in either direction that's allowed. That can be from srping to spring, like, if you buy a pair, they can be 100 lbs off between the two. And now you understand why people talk about 'lean'.


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[PontiacMatt72]

Originally Posted by HWYSTR455

The upper GW arms can be used with the AFX spindles, not sure why you thought no. There are 2 arms GW offers, either with or without the offset shaft, then you have bushing options. If by chance you need/want a different upper, it is very easy to sell the ones you have, and you can recoup almost the entire cost of whichever you already purchased.
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Doug at Global West says the UCA’s I have (CTA-42A) won’t work with the “tall spindle conversion” - which I assume would be the AFX spindle?

Listen from the 1:30 - 1:50 mark in this video:
https://youtu.be/7F23DVxZiDc

As for everything else, I’m definitely leaning toward going the route of the AFX spindles, proper UCA’s, whatever affordable brake package goes with the spindle, cheap tubular lower CA’s, and a decent shock/spring combo to get ride height where I want it.

I didn’t plan to spend that much all at once and hoped to do a little at a time. But such is life…

So, I guess tall ball joints have a place, but modern technology in control arms and the AFX spindle has provided a better option.

[HWYSTR455]

The 'tall spindle upgrade' usually implies using a 2nd gen F spindle.

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[JLMounce]

I would also not be so quick to go with a "cheap" lower control arm.

Part of correcting the GM SLA suspension is the ability to add additional positive caster. While many upper control arms do have the ability to make this possible, without a corresponding altered geometry lower control arm, you end up moving the wheel and tire aft in it's wheel house. Especially when using a wider wheel and tire package, rubbing of the inner wheel house and in some cars, the outer fender lip becomes an issue.

Lower control arms that come in a set with upper control arms that are advertised as geometry correcting typically add 1-2 degrees of positive caster in the lower arm. What this does is re-centers the spindle in the wheel house where it's supposed to be. If the arm still uses shim stacks for alignment changes, it also means that you need less actual adjustment in the upper arm to reach higher levels of positive caster (typically 5-6 degrees for a street application).

The tall knuckle corrects the camber curve in bump and droop. Positive caster increases straight light tracking and stability and importantly adds another layer of negative camber gain as wheel angle increases.

[HWYSTR455]

Yeah I hear what you're saying, but I specifically asked Doug regarding the lower arms, and he acknowledged there is no additional geometry advantage built into the lower arms. It's all in the uppers.

I spoke to Speedtech when I purchased the AFX for the 442, also acknowledged, there is no geometry built into their' (EDIT: bolt-on) lower arms.

The camber recommendations for the new gen AFX is different than the originals, they are less, and in the 4-5.5 range max. I personally run 4.75.

On the 442, I run the knock-off lowers, with the new gen spindes.

The Speedtech extreme chassis calls for 7-9.25 camber. There are specific reason they are like that, but I forget, it's been a while since I talked to them about it.

My GTO has 1st generation AFX spindles, which has the specifically created/designed lower control arms by GW. The change to using a common, standard lower control arm was made to prevent potential mismatch of parts. I will be switching over soon.
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[Joe-Touring]

I went with the SPC upper/lower arms with tall upper/lower Howe ball joints. The Savitske stage 3? Also went with SPC lowering springs and bilsteins. Im very happy with the setup. Kept the stock drum spindles, and luckily my (stock) tie rods ended up parallel to the ground, so my bump steer seems good.

I also went with the C5 Vette brakes front and rear and they are awesome, even without power assist. I know you’re already looking at doing 18s, but wilwood makes a disc conversion kit that allows you to go back to 15s, if you or the next owner would like to go back to a more traditional look.

Personally, I I think the AFX spindles are a tough purchase, unless you’re flush with cash. But they are trick. I think you’d get more bang for your buck if you put that money into sway bars f/r.

[Joe-Touring]

Originally Posted by HWYSTR455

My GTO has 1st generation AFX spindles, which has the specifically created/designed lower control arms by GW. The change to using a common, standard lower control arm was made to prevent potential mismatch of parts. I will be switching over soon.
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HWY, out of curiosity, what springs are you running? Since the AFX has a built in drop, I would imagine you have to run stock height springs?

[HWYSTR455]

When the car was in the 'MUT8SHN' config, a 71 LeMans, I ran lowered springs, think they were 575lbs rate.

When I went to the endura nose, I had to up it to like 650lbs, and a slightly taller spring. Mostly to prevent bottoming the suspension out.

Keep in mind I have free-articulating suspension, all del-alum, so requires a higher rate than factory type control arm bushings. Also have solid body bushings.

And no, before anyone asks, it rode fine, and not like a 'truck' like so many comments. Setup properly, it rides better than stock. Shocked all who rode in it, because it crushed the internet parroting narrative.

EDIT: To be more specific, I use Global West spring exclusively.


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[HWYSTR455]

The 442 also has Global West springs, the slightly taller ones, since for my daughter, I didn't want it in the weeds.


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[HWYSTR455]

I just did brakes on the 442, front & rear, rotors, calipers, pads, and SS lines, and it was less than $650.

EDIT: That's C5 fronts, Right Stuff rear, disc/disc.


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[Joe-Touring]

Originally Posted by HWYSTR455

Keep in mind I have free-articulating suspension, all del-alum, so requires a higher rate than factory type control arm bushings. Also have solid body bushings.

I’ve never thought about that, makes sense. Rubber always has resistance. I went with delrin bushings up front, it is very smooth. Thanks for the reply.


To OP: Another idea if you’re trying to save some coin is reuse your factory lower control arms, and replace the rubber bushings with Global West del alums. But you really wanna make sure that your LCAs aren’t cracked or damaged. Also, be aware that removing 50 year old rubber suspension bushings is not a good time.

[PontiacMatt72]

Reviving this thread.

Believe I’m ready to pull the trigger on the Speedtech AFX spindle. Here’s, I think, what the setup will consist of (for now?):

-Global West CTA-42A upper control arms (sitting on shelf waiting to be installed)
-Speedtech AFX Spindle (need to purchase)
-Stock Lower Control arm with Global West Del-Alum bushings (currently on car, newer replacement - not 50 year old originals)
-Global West steering arm to correct bump steer (purchased, uninstalled)
-reuse the springs currently on the car, and dial in with new springs if necessary.
-installed 18” US Mag Bandits earlier this year, so (hopefully) plenty of room inside the wheels for brakes.

I need help on selecting a *cost effective* front brake setup. Saw somewhere it was mentioned C6 “J55”/Z51 brakes are a good option? I did some brief checking and got lost trying to nail down the right part numbers, so some guidance there would be appreciated.

And, anything else I’m missing?

[HWYSTR455]

On the lower control arms, you would be better off buying the knock-off tubulars and selling the uppers to offset cost. Just make sure you get the ones that have the cross brace and change the ball joint and you're good. You might be able to find the lowers separately.

Like these:

https://www.ebay.com/itm/14541151464...3ABFBMxNyBvIFj

The steering arms are specific to the spindles, you would be better off buying the ones that Speedtech offer. I haven't seen the ones GW sells, didn't realize they made one for the AFX spindle. Do you have a link?

Speedtech offers 4 different steering arms, one is for 'enhanced' ackerman. I didn't opt for the tuning one, I use the one that's for standard tie rods, but it's up to you if you want to go that route.

Just to say, the GW 42A, AFX spindle, knockoff lower control arms, is the same setup as I run on the 442, and it works very well.

I have the Kore3 setup on the GTO & 442 as well, it's tough to find as good a deal for front brakes as they have: (the GTO has US Bandit 18s)

https://kore3.com/proddetail.php?prod=10336-01

Obviously, if you change to the drilled or slotted rotors, there's an upcharge. I recently replaced the rotors on both cars and used Powerstop ones, which are fine. Not sure on the pricing at the moment, but if they are less than Kore3, you can buy just the caliper setup from Kore3, they sell individual parts.

For $100 more, you can move up to the Z51 setup with slightly larger rotors, will still work with 18" I believe. Moving up to the Z06 size brakes I am not clear if they work with the bandits, but it's almost double the other 2 setups.

Honestly, unless you are doing serious track or autocross, going to the bigger Z06 brakes really won't give you much more. Replacement rotors also jump in price.

It's commented that the AFX spindles give you @ 1" drop, but I found it was less than that, and didn't have a problem with the springs I had on either car, but they are GW springs that are lower. I think trying the springs you have to start is a good idea.


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[HWYSTR455]

Breakdown on Speedtech ackerman & bumpsteer kits:

https://speedtechperformance.com/pro...mp-steer-kits/

Interestingly enough, when using the one kit, you actually swap side of the steering arms so the ends point outwards.

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[PontiacMatt72]

Oh, I wasn’t aware a standard steering arm wouldn’t work with the AFX spindle? Thought I read somewhere that a factory spindle would bolt to the AFX spindle. No? If not, that’s a kick in the nutz, as that adds another $500 to this deal.

AFX Spindle: $1,400
Brake kit: ~$800, or ~$900 for z51
“Budget” lower control arms: ~$175
Replacement lower ball joints: $30
Speedtech Steering Arm: $450-$500

Looking at around $2,850, likely more like $3k by time it’s all said and done. Shew!