I was doing some surfing on LS1 Tech and i came across these spindles made by American Touring Specialties. Nice set up 6061 aluminum constuction so they are ultra light.
http://i13.photobucket.com/albums/a262/pist0lpete/C5spindles.jpg
here is a link to their site http://www.t56kit.com/site.html

Damn, those are nice! A side by side shot of mine compared to this, would be very very sad :)

ATS spindle...due to be available this fall. A nice compromise of tall spindle geometry without the pitfalls of the poor steering linkage geometry.

I hear good things about the geometry and design of the spindle, but the fact they are aluminum I don't like.

I dunno those look pretty beefy. Not sure if they are cast or billet aluminum. If they are billet i would have no doubts whatsoever about their strength. However, they appear to be cast or forged. Either way id love to have them on my car.

...but the fact they are aluminum I don't like.

Keep in mind that just because things are made out of aluminum doesn't mean that they can't take the punishment. Engineers just have to do some predictive modeling for failure modes and adjust accordingly.

If you're really worried about a forged aluminum piece than don't ride in an '84 to present 'vette ;) Nor would you want to ride any motorcycles.

It can get even more scary. In fact...stay off a Britten V1000 (like any of us would ever get a chance to ride one of the ten made) as its front and rear girder type suspension is constructed from carbon fiber. :eek:

"Non-traditional" materials (if you want to call them that) can be safe to use as long as the testing and modeling have been performed in the correct manner & parallel what your theories have predicted.

The ATS spindle looks to be a nice "benchmark" off the C5 spindle (w/ a few tweaks) and made to adapt to early F, A and X body type suspensions. But I haven't seen any data to back up the claims. I'm sure it will come though. But I still have to question any hobbyist that puts ground effects on a first gen camaro ;)

Joe

Can anyone tell us the durability of 6061 aluminum compared to the GM forged spindles and how the two compare in hardness.
I believe I read that the Masterpower spindles are cast not forged.
Does anyone know if the Fatman spindle will be forged or cast and of what material?

65Camino
Team Gold Member #74

I now see that they are forged 6061.
Can anyone confirm the use of aluminum in Corvette front suspension parts

I hear good things about the geometry and design of the spindle, but the fact they are aluminum I don't like.

[Engineering Viewpoint]

The fact they are aluminum doesn't worry me, but what worries me is how experienced was the person doing the stress analysis, how much FEA was performed along with mesh sizing, constraints, and load cases, and finally how much actual strain-gauged mechanical testing was performed on a pre-production part(s) in order to determine the typical in-service fatigue life, ideally testing multiple samples to come up with a b-basis allowable. Finally, onto the manufacturing side, how controlled is the forging process, were sections done to verify grain flow/direction, was any kind of destructive or non-destructive testing done to verify the production process and the integrity of the forging, etc. All this analysis and testing doesn't come cheap and I worry that a small startup like ATS may not have covered all the bases. I may be wrong though, but the nagging doubt is with me, and a nagging doubt is a pretty powerful deterrant especially considering something as vital to your car as a spindle.

[/Engineering Viewpoint]

They do look really nice though. So far ATS has been pretty hush-hush about geometry and production-based questions; I hope they are more forthcoming after their debut at SEMA.

The other option out there is Marcus's G5 setup which uses modded C5 'Vette spindles; I would have a better "warm and fuzzy" feeling using those because even though they would not be used in their original application I'm quite confident GM did an overkill job designing them; they most definately have the resources at their disposal and they really have to do the job right from a lawsuit/liability standpoint.

Troy

Troy can you come tutor me in my stress class for engineering next semester? haha I see what you mean about the testing i would definitely not be one of the first people to buy them i would like to see some proven numbers and see that they can take a beating. Also i am curious about pricing i can only assume they will cost a pretty penny.

I'm quite confident GM did an overkill job designing them; they most definately have the resources at their disposal and they really have to do the job right from a lawsuit/liability standpoint.

Even GM had problems with their aluminum spindles on the new Z06s. Their first prototypes were twisting the spindles under heavy braking. :eek:

ATS did their homework on the geometry/design part of it, I just hope they did it on the engineering side too. They may be OK, I just don't want to be the guy that finds out if it's not.

ATS did their homework on the geometry/design part of it; I just hope they did it on the engineering side too. They may be OK; I just don't want to be the guy that finds out if it's not.
Let me add this-not to knock Tyler and his crew in any way but this spindle was not designed for the "A" body. It was intended to fit the Camaro and designed around that chassis. It happens to fit the Chevelle platform as well so like any good business owner they are reaching out to our market also. There are a number of things that could have been done to improve the design even further but it would have hurt the design characteristics for primary audience (F, X cars). I have seen all of the numbers that have been released (more then the magazines advertise but not all), they are better than stock, maybe even better than stock with tall ball joints.

Now I wonder how running those in conjunction with tall ball joints would look....hmmmm.

What would be the downside of running these on A-bodies,Dennis?
I've kicked the idea around of buying a pair of these and adding the new Z06 brakes to them,,then selling my Baers to help pay for it all.

It's not so much a downside as it is that if they were designed for "A" bodies they could be better. The spindle pin needs to be raised some more and the spindle needs to be taller.

Do you guys really like the sealed bearing unitized hubs? I don't do much FWD suspension work, tend to only end up doing it for family and friends once in a while, but usually it's something to do with those hubs. And the guys with the late model 4wd trucks running 35's will know, too. They usually last about a year with big tires, from what I've seen. Got a few friends who play that game. Saw one guy lose his wheel once, hub and all was gone. :eek: But back to these, if you're seriously hammering some corners, with big tires, what's the life expectancy of these bearings? Corvette guys having any trouble with them?

Edit: I've thought about this a bit more, might be comparing apples to oranges, since these don't have an axle running through them. Still open for thoughts, though.

This is an interesting topic because I was also looking into these spindles. First off when I checked they go for $850 for the pair. The engineering aspect behind them has gotten me kind of worried. I am not a mechanical engineer but I would definately like to see some stress testing results for them. I like the idea of being able to run c5 brakes. 10.5" rotors just don't cut it.

The spindle pin needs to be raised some more and the spindle needs to be taller.By how much? Both could be accomplished by running tall lower ball-joints.

No, the pin needs to be raised about 2-2.5" and the spindle height needs to be at least 10". Taller ball joints will help but not accomplish that.

The engineering aspect behind them has gotten me kind of worried. I am not a mechanical engineer but I would definately like to see some stress testing results for them.I know both the owner of ATS (Tyler) and the engineer of the spindle (Shane). They are plenty strong and went through as much stress analysis as any part need go through. BTW, the Corvette has been using Al spindles for ~15 years.

Hello all.
Glad that our spindles made their way over here. I'm sending in my engineer, Shane to address all the concerns you guys have regarding the strength and durability of the AFX spindle, and I assure you that no expense was spared on the engineering, forging, tooling, or testing of these spindles. They will exceed factory C5 spindles in every aspect.
That being said, I'd like to throw out a quick message to 72SSABody-
I didn't just put ground effects on my car. I cut the entire thing up. An orginal RS/SS BBC car with zero rust. :D

Shane will be in shortly to put all issues to rest with soild tech. We did our homework on this one guys, so start thinking of what you'd like to know about them, because we are open for a good tech session.

Tyler

Does that mean I get an advertiser discount? No I am kidding but all kidding aside I think you guys have some great products. If you guys started doing for the chevelle what you have done for the camaro I know you could get alot of business. There are plenty of guys on here that would buy your products. Keep up the good work.

Alright guys I'll try and layout our design process for these spindles based on your inquiries and concerns. First let me state that yes it is extremely expensive (especially for a two man team) to replicate all the tests that parts have to endure in the OE's, but we have tried to cover all the aspects of the test and design phases to our capabilities by contacting multiple engineers in GM, other suspension engineers, and different vendors involved in designing the C5 knuckle in order to achieve these goals.

In the initial stages we fabricated a test spindle much like the Stielow spindle but utilizing a C5 bearing cartridge and an adjustable steer arm. We acquired control arms from Global West, DSE, and Speetech and did camber curves, caster curves, plotted pivot points, in both the stock location and gulstrand location for both the AFX spindle and stock spindle. This was done to know our baselines and to be able to tell the customer how our spindle will work with any combination and how it will affect their application. We are currently in the process of working with SC&C to do the same for the A-body platform so we can accomodate those that have already done the B-Body spindle conversions and have the shorter UCAs and also to design an UCA that is specific and optimized for the AFX spindle.

All the components for the orginal fabricated spindle and current forged spindle were modeled in Solidworks and had simple wheel load FEA done on them by both myself and the forging company since we already knew the fabricated spindle has taken a ton of abuse on the Thrasher Camaro. I have taken specialty classes in both finite analysis using ANSYS and strain gauge testing. Next we got in contact with one of the original reps that worked for the manufacturing company that did the C5 pressure cast aluminum spindle. He was able to tell us the constaints and requirements that GM demanded for their design. The C5 spindle is actually a pressure cast A356-T6 alloy while ours is a must stronger forged 6061-T6. For those that want numbers The UTS is 228 MPa vs. 310 MPa, Tensile YS is 152 MPa vs. 276 MPa, and Elongation at break is 3% vs. 12% for the C5 vs. the AFX materials. Our selection of material was discussed in long detail and initial FEA was done based on our current model by both myself and the forging company taking in to account a safety factor of 5. Not only is our spindle more ductile but it is also a lot stronger and those that know how forging works know how the grain structure is worked so that it flows in the direction of the part for optimal strength. The AFX is also almost 1.5x thicker everywhere than a C5 spindle. Now let me say that the FEA was used just as a tool for the design process not as a corner stone. I will get into the true destructive testing later.

Other aspects that we looked into and talked with GM engineers on was one thing that was stated above about the new Z06 twisting the brake bracket which I can concur was true. They had to redesign the spindle to be beefier for the 6-piston calipers. We took this knowledge and also incorporated about a 50% thicker caliper bracket which is also reinforced into the lower ball joint with stratigically placed variable fillets. Another issue plaguing the C5 knuckle was the lower ball joint taper fatiquing after each torque cycle of the ball joint. We took care of this issue by introducing harder 7075-T6 inserts that are frozen in liquid nitrogen and placed into the extremely precision machined holes of the spindle, which upon reaching room temperature maintain an adequete interference fit. On top of the interferance fit we use heavy duty spiral locks with an additional tensile strength of 211,000 psi to prevent any initial backing out on top of the interferance fit and mostly to reduce the risk of tampering.

Now onto the manufacturing. Number one is quality control and precision. The forging company we chose is in the USA and has been in business for over 40 years doing stuff for both military and the OEs. Each and every raw forging is inspected and 1 out of 10 has a tensile sample ran with it to check the material properties and their consitancy. Also we recieve a certification sheet showing the critical dimensions for each part and their tolerances. The machine process involves a 7-axis CNC with an integrated CMM probe to maintain all the stringent tolerances that are called out. I personally have 2 years of experience working with quality control and operating a CMM so I have a really good grasp on what I am looking for and what is required. Some may argue that some of this is over kill, but all our products must be top notch regardless if this is just the aftermarket.

Now on to the testing. We are in the process of contructing a pretty elaborate test station that will simulate wheel loads on the spindle and record the loads and deflection in the spindle. We plan on taking it to the point of failure multiple times. We are also putting a few sets on some Camaros right now that will be running on some road racing events later this month and running very wide tires. They will be putting some serious loads on these spindles. The road testing will be an on going operation that we will be tracking even after we start selling the AFX spindles. We are also working with another GM engineer to meet any other validating tests that he thinks are necessary. With all this said you can see we are going all out to make sure that these are safe, sound, and proven. As an engineer myself I can understand some worries with such a critical part of your vehicle and thats why we are being so aggressive with them and I am personally going to run them on my 87 Grand National. We have worked with the experts on these and I can guarentee we have a product that is of high caliber. Please let me know if you have any other concerns or questions.

I also wanted to add that our pricing currently is $625 a pair with brand new C5 hubs and all the hardware. BTW dennis thanks for the nice comments and as for the spindle height the tall version is 8.5" tall and with 1" taller upper and lower ball joints that would get you your 10" tall spindle along with a 1 7/8" drop. Like I said we are working with the A/G body guru Marcus at SC&C since he has a test frame to optimize this for that platform.

OH and by the way you don't even want to know what I'm doing to my 60k original SS 1970 Chevelle....
Shane

Shane,
This sounds really good (enthusiastically)....we've been waiting for a product like this for a long time! A safety factor of 5!
If I understand your website product info on these spindles, some of us plagued with the infamous bump steer problem of other manufacturers and spindles with long steering arms can use your spindles with some of our current "brand x" parts....? Say for instance that I just happen to have the tall B spindle setup with a complete...lets say Baer brake system....lets just say....I think I am reading that I can adapt my brand x calipers to your spindles...and what about the hubs, will they work also? Lets just say I am running the Baer eradispeed+ 13" rotors and hats with a chevy bolt pattern....
The product and tech data all look and read real good, really looking forward to this a lot! Keep us posted.
Sam

Sam,

You can use any steer arm made to fit the orginal A, F, and X body platforms like those included with different rack and pinion kits, BUT the spindles are designed to accept factory F/X-body steer arms and are calibrated for minimum bumpsteer for those. Therefore the factory a-body and others will not be obtimized for the correct bumpsteer that is why we are making specific steer arms for the other platforms to optimize the bumpsteer.

As for calipers, the AFX spindle accepts ANY caliper and rotor for a C5/C6 corvette. If you have a kit for a A, F, or X body from Baer they are using C4 calipers that currently will not work due to the bolt spacing and the large offset in the rotor. The same goes for the B-body spindle setup. We are currently working with Baer to make an adapter for the C4 caliper to a C5 rotor, but I would still suggest using C5 components so you do not have to wait or use an adapter. The AFX spindle uses a sealed hub assembly from a C5 corvette so obviously other hubs made for a kingpin would not work. Please let me know if you have any further questions.

Shane

Shane/Tyler, thanks for popping in. You addressed just about all of my engineering "concerns" and consulting with experienced persons (namely GM and the forging company itself) goes a long way towards putting my inhibitions to rest... not only because the constraints used were the GM constraints but that there's a 5X factor of safety put into the original model using those load cases and constraints. While a 5X FS is overkill for a racing application where every pound matters I think that was a VERY wise choice for a product which will primarily see street use; I'd gladly sacrifice a bit of unsprung weight for higher margins given the criticality of this piece.

Have you performed any destructive testing yet to verify your predicted vs. actuals?

Hopefully you guys and Marcus will get some numbers posted up soon, as I am definately on the "potential customer" list. I've been watching this spindle for quite some time but being an engineer myself I tend to hold off on the final decision until I have all the data in-hand, which sounds like it will be in the not to distant future.

Troy

Troy,

Glad to hear I answered your questions. We are in the process as we speak to doing the destructive testing. We will have a lot of data soon. We are pretty excited about this product as are a lot of others. We are looking to have the F/X body platform done by the holidays and the A/G body kits available sometime in January. We'll keep you all posted. Thanks again for your interest in ATS products.

Shane

That being said, I'd like to throw out a quick message to 72SSABody-
I didn't just put ground effects on my car. I cut the entire thing up. An orginal RS/SS BBC car with zero rust. :D

Tyler

:thumbsup: I can see the "original" enthusiasts gasping as they hear that statement while sitting in their "car show" lawn chairs.

That all aside. I can count three BSME's posting on this thread. Plus a few guys on here that will break your parts after they have a chance to do some "real world" driving :D

So after reading your response, Shane, can you tell us what your predictive modeling parameters & FEA analysis (I'm assuming you used COSMOS if you modeled the part in SolidWorks) were like when you added aluminum into the equation?

After all, cyclic loads (both temp. cycles and load cycles) play hell on aluminum parts (that's what the guys in here were referring to when the "aluminum" word was brought up).

Joe

... being an engineer myself I tend to hold off on the final decision until I have all the data in-hand...

Troy, I was in the same boat, but Shane and Tyler were kind enough to share with me some juicy information at SEMA about these spindles. I'm sold.

The pictures do not do the design justice. The construction, fitment, and engineering in these spindles, IMO, put them into a category all by themselves. They even meet my anal needs for easy repair by using a hub that is available at any GM dealer.

I also agree with Sam, this is the kind of product I've been waiting for.

Troy, I was in the same boat, but Shane and Tyler were kind enough to share with me some juicy information at SEMA about these spindles. I'm sold.

The pictures do not do the design justice. The construction, fitment, and engineering in these spindles, IMO, put them into a category all by themselves. They even meet my anal needs for easy repair by using a hub that is available at any GM dealer.

I also agree with Sam, this is the kind of product I've been waiting for.

Good to know Carl, and I know you'll subject them a proper "on-vehicle test program." :thumbsup: I'm still waiting for the A-body numbers though... inquiring minds want to know camber curves, RCH, and RC migration numbers, both with and without Howe tall ball joints on the A-body platform. My hope is the numbers will be quite good with the tall ball joints-- good enough to make it hard to justify going with a custom spindle.

If these spindles pan out there's a very good chance they'll find their way onto my car along with a set of new Z06 calipers. And with the reluctor wheel provisions on the ATS spindles I'm starting to look into what it would take to adapt an ABS system onto the car. :D

I'm dying to open track my car and really beat the crap out of it but I still need an intercooler, oil cooler, and better oil pan before that happens. Right now my water injection works quite well but the tank would probably run dry after 2-3 laps on a track (intercooler will take care of that), I can get my oil up past 260F from hard driving on backroads (oil cooler will fix that), and I can also get my oil pressure gauge to flutter under hard sustained braking and cornering on backroads (good oil pan should take care of that), so tracking my car in its current state is guaranteed death for the engine in three different ways. I can almost cook it on the street, so I *know* I would kill it on a track, probably in the first couple laps. :p

Back to the spindles, I also like they incorporate an off the shelf hub and bearing pack. Makes replacement easy.

Any idea on what brake options will be available in a 13" rotor as I want to keep a 17" wheel on the front that would be an upgrade from C5 calipers? Willwood, Brembo, AP?

tracking my car in its current state is guaranteed death for the engine in three different ways. I can almost cook it on the street, so I *know* I would kill it on a track, probably in the first couple laps. :p

Good call. It's better to upgrade it up front than to break it at the track and fix all of it. My wallet is living proof of this phenomenon having learned it the hard way.

If you want to find every weakness in the cars' systems, a hard-driven 20 minute road coarse ride will find them all.

Any idea on what brake options will be available in a 13" rotor as I want to keep a 17" wheel on the front that would be an upgrade from C5 calipers? Willwood, Brembo, AP?

I would think you could probably fit Wilwood 6-pistons under 17" wheels, or maybe the new Z06 calipers. I can't really imagine any caliper/13" rotor combo that wouldn't clear a 17" wheel; the PBR calipers are already rather chunky and even with 13" rotors they clear 17" wheels without any issues.

The other option I'm digging into is the Brembo calipers used on the Caddy V-series cars. The CTS-V calipers appear to be 4 piston Brembo units and look quite nice and can be had for a very attractive price, but an adapter bracket may be required. The ATS spindle should take any C5/C6 brake kit with zero mods, so that's probably the best route to investigate.

Troy

Brake wise, we can get most anything C5 based to fit. We are an AP dealer if that is the route you'd like to take:
http://www.pro-touring.com/~tylerb/AFX4.jpg
http://www.pro-touring.com/~tylerb/AFX3.jpg

Tyler

My MovIt kit on the C5 uses a Brembo Big Red claiper/rotor setup off a Porsche 993TT. The kit uses the stock lower mounting bolt for the stock brakes but mounts the upper side of the caliper using a bolt from the bearing pack to hold the adaptor bracket, not sure if it'd work on the spindle.

What size are the rotors on the AP setup?

The rotors pictured are 14"x1.5" 2pc full floaters.
Tyler

The rotors pictured are 14"x1.5" 2pc full floaters.
Tyler
I have 2 friends that run a 14" AP system on their C5s. The braking force is mind bumbing.

Tyler/Shane:

A question I would like to know (and I'm sure others would as well) is what is the track width change with the AFX spindles compared to the following applications:

1. AFX vs. Factory Drums
2. AFX vs. Factory Discs
3. AFX vs. B-body spindles

Troy

Our spindles are the same track width as a stock spindle with disc brakes. So, from a drum application, it will move the wheel out 1/4", on factory disc, no change, and on B body- Well, I have no idea. Where does a B body place it?

Tyler

IIRC the B-Body spindles widen the track by 1/2-5/8" per side over the factory discs.

Just wondering, because some of us are considering ordering a set of CCW wheels and want to make sure they're backspaced correctly both for now and for "future upgrades." :D

I'll probably play it safe and wait until I decide how to tackle the front suspension before ordering wheels... backspace changes ain't cheap!

Troy

Joe,

I wanted to get back to your question about the design parameters and the use of aluminum so you didn't think I was defering the question, just extremely busy.

Basically as I stated before, setting up a test station that emulates typical cyclic loading conditions and predicts short, long, and/or strain fatigue lifes would be out of our bounds to create financially. BUT, I did do extensive research on tests and papers conducted and written by other engineers hired by the OE's. Basically the tests included lab testing of a cast aluminum (of the same grade as the C5) to cast iron and forged steel steering knuckles along with deriving equations to predict their behavior. Now as a side track...

In the forging process, hot working refines grain pattern and imparts high strength and ductility, therefore forged components have lower possibility of internal defects, whereas castings are weaker in this respect. In addition, lower ductility of castings limits their capacity for cyclic plastic deformation which often occurs at stress concentrations and at overloads, and therefore
shortening their fatigue lives. But as stated before in this forum, regardless of the manufacturing procedure, yes.. Aluminum itself doesn't exhibit an endurance limit, meaning that even with a miniscule load, they will eventually fail after enough load cycles.

With that being said we applied the material properties of the forged 6061-T6 to the models that were derived from these tests to predict the fatigue life of our spindles compared to both a cast aluminum spindle and forged steel spindle. Basically it breaks down like this in terms of cycles to failure. The forged steels fatigue life is about 2 orders of magnitude longer than the cast aluminum and about 1.5 orders of magnitude longer than forged 6061-t6 assuming the same stress amplitude. Now assuming the same wheel loads in cornering on a C5 cast knuckle, a fabricated steel knuckle (Stielow), and our forged knuckle models I saw a lot lower levels of stress in the forged spindle due to its cross sectional area and design which also includes the greater safety of factor against yielding. FEA was done both in Cosmos and ANSYS using different mesh sizes along with smart meshing (very fine edge lengths in critical areas) was looked at for consistant results. Like I said before we will be conducting the physical destructive testing within the next week or so to substantiate some of those results.

Simply put these were designed to meet or exceed the design of the C5 knuckle where ever we could using the resources we had. We will be monitoring many sets as they get mileage put on them to look for any stress cracks or signs of fatigue to conclude our assumptions, but this will obviously take time. I urge everyone to do the research yourself. Compare the materials, and you don't even have to be an engineer to see the obvious improvements in bracing, contours, and thicknesses on top of the better manufacturing process and material properties as compared to a C5 knuckle. These things were designed to be beaten on period!

To simply answer anyones question on fatiguing...yes there will be a service life on these, but we are talking around 15-20 years. And believe me all specs like this will be laid out in the instructions including proper torque values, alignment specs, and maintenance.

Shane

Reading right along.

pdq67

What up pdq ??

Did you ever list a price for a pair of these spindles?

Okay. I've read this thread front to back like 4 times. I still don't understand what the problem is using these with the stock steering arm??? Sorry if it's been covered..

I'm certainly not the expert here, but I'll give it a try.

I believe the main problem with using the stock steering arm is that the position of the rod end ends up too high?? in relationship to the lower ball joint and you'll actually introduce more bump steer over the factory suspension. These spindles and arms are designed more for the f-body guys, but have definite improvements over the b-body spindle conversion and others.

You might be interested in the SC&C tall ball joints. Those use the factory spindles and accomplish the camber improvements.

But...you can't beat the coolness factor of these spindles.

As the steer arm for these spindles is a bolt on, an arm can be designed and made that has zero bump steer. That would be the advantage of this setup.
Tall spindle + zero bump steer = resolution to tall vs stock spindle debate. :)

Of course there are other factors (cost, wheels, strength, etc) but I think for many people these spindles, with the correct steer arm, will offer a nice compromise of price and performance for a spirited street car.

Clint-
Pricing is currently at $625 per pair with the new C5 hubs already installed. The custom ATS steering arm would be an additional cost.

LateNight72-
The stock steering arm could be used as a last resort. The issue is a bumpsteer problem because of the A body being a front steer vehicle. We lowered where the steering arm attaches to improve the bumpsteer on the rear steer F body cars, and by doing so we increased the bumpsteer on the A body. We are working with Marcus at SC&C currently to get the optimal combo dialed, and then release a combo of a steering arm, spindle and control arm package that will redefine the way the vehicle handles; in a positive way.

I'm not sure if Marcus posts on this forum or not, so I'll quote what he said about our AFX spindles on Pro-Touring.com:

We`ve started working with ATS on some new applications for their AFX spindles. I actually have a pair (one tall,one std. height) right here on my desk (jealous? ). I have to keep a lot under my hat but I`ll try and give a few impressions at least.
First I wanna give ATS kudos for actually going out of their way to encourage independant testing of their parts by another company in the same industry. I don`t know of any other company in the field that would do that!
Second I want to say that they`ve really got something here. The quality of the parts rivals (and in some ways exceeds!) factory GM C5/C6 knuckles (which we have a LOT of experience with). We`ve just started our part of the testing and fitting but a few things are apparent already.
A) They`ll be fairly easy to adapt to other platforms (most with just a steering arm and BJ taper change).
B) The tall AFX spindles "can" be used with stock arms BUT even with offset shafts you may be limited (possibly very limited!) in what alignment settings you can run. This depends on ride height and other variables as well. This isn`t a criticism just a fact caused by any meaningful geometry change. Typical tubular arms will help in the caster dept but very little in the camber dept. Adj. arms like ours will allow a full range of street or competition settings with no restrictions regardless of setup and no possibility of ball joint binding in bump.
C) The stock height AFX spindles will work well with the G mod, our Stg.1 or 2 packages or both! The tall AFX spindles respond well to our tall upper ball joints for hardcore and track use. This combo is still shorter than the big spindle extenders and due to the slight drop in the spindles the arms are in a different possition also which help prevents the FVSA length and RC height from getting out of hand.
D) The tall AFX spindle should be adaptable to 2nd Gen F body (or B body for that matter). The interchangable ball joint tapers will take care of the basic fitment. A new steering arm will be required (longer and with a different vertical offset). The geometry will remain essentially unchanged but camber gain and RC location can still be greatly improved with our tall ball joint Street Comp packages. These cars don`t need as much improvement as the 1st gens in the first place. This would be a very nice way to go to get a MUCH lighter spindle with C5/C6 brake mounting and huge wheel bearing assys.
E) We`re very impressed with the AFX spindles,to the point that we`re becoming a dealer and will be offering them as is or as part of a new line of Street Comp packages. :D Marcus SC&C

Hope that sums it up for you guys. We are more than happy to answer any additional question you guys have regarding our new AFX spindles.

Tyler