Hi Guys,
I am a bit confused and need some solid confermation on which GW Upper Control Arms are the correct one's to use with the AFX TALL spindle on a 69 Chevelle. I get conflicting information wherever I look.
I currently have the GW Negative Roll set-up with B - Body Spindles which use the CNR-42A upper arm and I am switching over to the AFX TALL Spindles w/B-Body BJ inserts and steering arms.
Here is my confusion:
1.) The GW web page says that the CNR-42A will not work with an AFX spindle but also says it will work with a 8-15/16 GM spindle.
2.) Tylers web site says to use a CNR-42A with the TALL AFX spindle. But I e-mailed Tyler and he said to use a CTA-42A :confused:

Am I missing something here or are there others with the same confusion? Or, has recent testing showed that the CTA-42A actually works better. I am hoping that Marcus will chime in on this one since I know that he worked with Tyler on the initial development and testing.
Derek: Do you have any info available that might solve this delema?
Just for clarification here are a couple of pics of the 2 different upper arms.

CNR-42A
http://i189.photobucket.com/albums/z189/F1Speed/cnr-42a20ph2.jpg

CTA-42A
http://i189.photobucket.com/albums/z189/F1Speed/cta-42a20single.jpg

I just went through this very problem, Mark at SC&C and I worked it all out in a fairly lengthy phonecall as I'm in the middle of swapping my GW B-body setup to ATS tall spindles.

The issue is the GW "negative roll" (i.e. B-body) upper arms (CNR-42A) are designed to have about 0 degrees camber with NO shims and the B-body spindles. B-body spindles have a 10 degree kingpin inclination angle.

The ATS tall spindles have 8 degrees KPI, so with the GW CNR-42A uppers and no shims you are looking at about -2 degrees camber. That's not good. Basically, you'll probably wind up with too much negative camber and you can't get rid of it because you are out of shims.

Case in point: On my car right now I have B-body spindles, GW lowers, and GW CNR-42A "tall spindle" uppers. My frame was rolled a couple years ago due to sag (I ran out of shims) and is now at the widest end of factory spec. I have -.5 degrees camber with only 1/8" of shim per side. If I were to bolt the ATS spindles on I would have about 2.5 degrees negative camber with only 1/8" of shims. There is no way I could dial all the negative camber out. The CNR-42A arms are just too short for the reduced KPI of the ATS spindles.

Thus you need to use the shorter GW "stock replacement" arms, the CTA-42A with the ATS spindles in order to allow enough shims to properly align the car. You'll probably end up with a fairly healthy shim pack but at least you'll be able to achieve a reasonable camber angle.

Honestly, I would skip the GW uppers and buy SPC turnbuckle adjustable uppers from SC&C. I currently have GW upper and lower arms on my car with B-spindles and I have ATS spindles inbound. I already have the SPC adjustable uppers. With the SPC arms there are no alignment shims to worry about, no worries about running out of shims, and no worries about getting the right caster adjustment due to cross-shimming limitations.

If you already have the CNR-42A uppers like myself-- you're SOL and will need to buy new upper arms. It was an unplanned but necessary expense once I got on the phone and started talking to Mark. Once he gave me the KPI specs between the two spindles I knew I was going to need new uppers.

How's the car coming? Haven't seen any pics other than the ones at MWPE you posted a looooong time ago!

SPC arms, doooo it.

Gokou hit the ol nail on the head,you need CTA-42A. Or E Bay the whole B swap mess and start clean sheet with SPC arms and make some cash on the deal. :thumbsup: Mark SC&C

Im in the same boat (have the hardware but went frame off before I did the swap) - arms have never been installed, b spindles are por'd and never been installed, 1le brakes are new and never been installed, etc - Not to hijack here but :

Are people still buying these up? Since you guys are either in the industry or well versed - whats the sales potential? I know I need to off them to get what I want (not a whats it worth request) but with all the new suspension stuff out there, SC&C, etc I thought this may be a hard sell.

Im in the same boat (have the hardware but went frame off before I did the swap) - arms have never been installed, b spindles are por'd and never been installed, 1le brakes are new and never been installed, etc - Not to hijack here but :

Are people still buying these up? Since you guys are either in the industry or well versed - whats the sales potential? I know I need to off them to get what I want (not a whats it worth request) but with all the new suspension stuff out there, SC&C, etc I thought this may be a hard sell.

It's a more difficult sale now that the word is out. Had I bought ATS spindles very early on before the word of a "better alternative" was so widespread I could have sold my B-body stuff easy. Now that the word is out it's more difficult to sell the B-body stuff. Case in point, the buyer for my upper arms and B-body Baers fell through last week. I'm going to try selling the B-body brakes only on a 2nd Gen F-body board as it's a direct bolt in for those guys.

As far as the upper arms, I'm sure someone out there would want a set of CNR-42A's in mint condition... I'm hoping I can find that person on ebay. :p

It's a more difficult sale now that the word is out. Had I bought ATS spindles very early on before the word of a "better alternative" was so widespread I could have sold my B-body stuff easy. Now that the word is out it's more difficult to sell the B-body stuff. Case in point, the buyer for my upper arms and B-body Baers fell through last week. I'm going to try selling the B-body brakes only on a 2nd Gen F-body board as it's a direct bolt in for those guys.

As far as the upper arms, I'm sure someone out there would want a set of CNR-42A's in mint condition... I'm hoping I can find that person on ebay. :p


lol....alrighty...what say all you cats stop talking up this SC&C stuff, Marcus, stop pushing your product, just take a hit for a lil while, go on vacation or whatever... so's those of us needing to sell off GW stuff can get it done and get the good stuff.

We need a "talk up the GW and B body" campaign so we can sell. ;)

Sorry Beaux, I can't do it. I'm waiting for the B-spindle/big-brake setups to really hit rock-bottom, so I can upgrade my 95 Caprice brakes for pennies on the dollar. ;) ...people forget these B-body parts also fit B-body cars. :D

Troy and Marcus, thank you for clearing up the confusion and the clear explination of why the CNR-42A's will not work.

The CNR-42A arms are just too short for the reduced KPI of the ATS spindles.

I am just assuming that even with the offset cross shafts (which I have), I still wouldn't be able to dial out all of the negative camber.


Thus you need to use the shorter GW "stock replacement" arms, the CTA-42A with the ATS spindles in order to allow enough shims to properly align the car.

Troy, did you mean to say "longer" stock replacement arms? I thought that these were longer but I don't know for sure :confused:.

I actually have two 69's one of which I had to put in storage so I could finish the newest one. As you can see from the pictures it's time to start on the front suspension but I wanted to take a little different approch than what everyone else is doing. Would you care getting into a discussion about few "outside the box" ideas I have?

As far as the rear of the car, I think I have it pretty much completed. The 11" rear springs seem to be a little to short (the adjusters are cranked UP about 3/4 of the way) but I need to get the front end down first before switching to a 12" spring.
I need to get going on the 6 point rollbar for the inside and I got everything I need from Mike Lewis to build a nasty little 396.

http://i189.photobucket.com/albums/z189/F1Speed/DSC00849.jpg


http://i189.photobucket.com/albums/z189/F1Speed/DSC00844.jpg


http://i189.photobucket.com/albums/z189/F1Speed/DSC00846.jpg


http://i189.photobucket.com/albums/z189/F1Speed/DSC09284.jpg

Just a final point for clarification, can you still use the GW LOWER control arms with the ATS spindle as long as you change to the SC&C upper arms? Thanks alot for the discussion/explanation in this thread.

Mike--

Yes, that was a typo above. I meant to say the GW CTA-42 arms are longer and thus you can get a good alignment with them. Still, after playing with my new SPC arms I don't know if I'll ever go back to a shim-based upper arm again... unless they use caster inserts in the cross shafts like circle track cross shafts and DSE use. I just don't like having to cross-shim for caster. The SPC arms are just soooooo easy and you're not fumbling for shims or limited to whatever size shims are available.

Personally, your rear ride height looks way too high right now (for my tastes anyways.) I tried 12" springs and sold them, too high. Went back to 11" springs which put the wheelwel 1" above the lip on 17" wheels... perfect. Nice and low but I can still go over speedbumps and go in and out of parking lots. Depends on how you have your screwjacks setup though. Are those rear wheels 18"? If so bring the back of the car down until the wheelwell lip is about 1/2" off the top of the wheel and now you're at the ride height of my car. Unfortunately then you run into problems like driveshaft to floor clearance... and have to cut your entire tunnel out. Still finishing that project up.

I'm intrigued now about your front end, what "outside the box" stuff did you have in mind?

Just a final point for clarification, can you still use the GW LOWER control arms with the ATS spindle as long as you change to the SC&C upper arms? Thanks alot for the discussion/explanation in this thread.

Yes. Just get the AFX spindles with the correct LBJ insert for whatever version GW lower arm you have. I'm keeping my GW lowers, they are very nice pieces and I didn't see any reasons to swap them out.

do want to start an argument but I had the tuffest time selling my b-body spindle and GW negative roll. but finaly did. Then I bought ATS spindles and a different set of GW arms which are in your first post pic #2 and I love it the fitment everything about them they will do what is needed of them with my ATS tall spindle

oh and on top of that I am using my lower arms I already had and had the spindles fitted for b-body upper/lower ball joints tyler is the man

Troy, Yes those are 18's and I agree I'm still to high in the back. I know when the front comes down the rear will come up even more thats why I want to wait until I get the front complete before I start messing with the rear springs any more. The rear is super easy to adjust ride hight, takes less the 5 min. with one hand on the ratchet. Super smooth.
Question, What if a guy were to modify the CNR based arms by adding a screw in ball joint coller and moving (lengthening) the ball joint center line out 1/8" to 3/16" farther outboard? I have confirmed that it can be done but I am unsure of the end results.
I agree with the caster inserts also. Was thinking about having the offset shafts machined for caster slugs. I actually have all the parts for both mods but I have not had the time until now to go forword.
I know that I could just go with the SPC or GW CTA-42A arms and be done with it but what fun would that be. I am out here in Colorado and everyone is running the SPC arms which are very nice but I wanted to try something "outside the box" along with a couple of other things that I have already confirmed that works :D.
Just need to bounce these last couple of ideas off a couple of you guys to see what you think. I'm hoping that this does not turn into a thread or idea bashing thing like on other boards. Already been there once and it sucks won't do it again!

Interesting idea on the upper ball joint offset. GW uses a press-in Vega LBJ for the CNR-42 upper arms which kind of limits your choices.

As far as it working... I just did a quickie autocad drawing. For a 8.75" tall spindle (B-body height and very close to ATS tall) you need a shim pack of about .305" to change in the upper arm length to produce the +2 degree camber change necessary to compensate for changing from B-body to ATS spindles. I don't think you'll get that much out of an offset UBJ nest.

Caster slugs are nice but they would have to be done probably in conjunction with replacing the factory press-in upper studs with standard bolts. I think GW should offer their arms with replaceable caster slugs-- heck, I even talked to Doug about that about 7 years ago when I bought my arms (I got one of the very first pairs of A-body lower arms they made.)

The issue I see with caster slugs is clearance-- I can't see being able to get the slug out of the front driver's side without steering shaft and/or header interference if still using the factory press-in studs... but those are very easily removed and replaced with standard bolts you could slide back to remove the slugs.

But from my realist standpoint... by the time you rework your upper arms you probably could have just been money and time ahead buying SPC arms. :)

Sorry Beaux, I can't do it. I'm waiting for the B-spindle/big-brake setups to really hit rock-bottom, so I can upgrade my 95 Caprice brakes for pennies on the dollar. ;) ...people forget these B-body parts also fit B-body cars. :D

dammit, man.....lol :D


You're wise beyond your years, for certain...

here is a pic of mine GW upper and lower arms with b-body Ball joints and an ATS Tall spindle

http://i99.photobucket.com/albums/l315/Rantheman96/chevelle105.jpg
http://i99.photobucket.com/albums/l315/Rantheman96/chevelle103.jpg

I wonder how much the CNR-40-A GW Upper Control Arms (Purchased 14 years ago) differ from the CNR-42.

GW originally issued these for the tall F spindle upgrade to the A body cars.

Currently I am running B spindles on the car with the AFX spindles sitting on the workbench waiting their turn. Got all the parts just need some warmer temperatures to get out in the garage.

I wonder how much the CNR-40-A GW Upper Control Arms (Purchased 14 years ago) differ from the CNR-42.

I believe the "improvements" to the CNR-42 included billet steel offset cross shafts, additional bracing for the downtravel limiter, and a change to a press-in balljoint and added the snap-on aluminum beauty cap over the balljoint.

At least that's what I vaguely recall reading on GW's website 7 or 8 years ago right when they came out with the CNR-42 "Generation 2" uppers.

Troy, Thanks for the quickie CAD mock up info. Just for further clarification, I think what you are saying is that I would have to move the ball joint out board on the CNR-42A's approx. .305" to get a +2 degree camber change. Am I correct?
Hmm, I'm looking at these stripped dowm arms and this srcrew in ball joint coller and thinking that this is very doable. I'm lookin at these cross shafts and thinking the machine work to do the caster slugs is very possible also. I think I need to get my hands on some caster slugs to be sure though, Looks like a quick call to CV products is in order.
Ya, I know what your thinkin. Why spend the money to take a chance on something that may or may not work, right. Well for me it's all about the "outside the box thing". I'm weired that way :D. Gotta try something new.
Your feed back is a big help and greatly appreciated. I'm diggin this colaboration of the minds. Keep it commin.

All right guys,,, I am in the same boat so here is my question. I totaled up how much I payed for my upper GW stuff. CNR 40- 1 w/t del alum's, Wilwood big 4 piston calipers and 13 in slotted / plated roters = $3195.00 never used. How much of a discount should I put on these to move them and get the right stuff. ? To get the right stuff is about $3200.00

Troy, Thanks for the quickie CAD mock up info. Just for further clarification, I think what you are saying is that I would have to move the ball joint out board on the CNR-42A's approx. .305" to get a +2 degree camber change. Am I correct?
Hmm, I'm looking at these stripped dowm arms and this srcrew in ball joint coller and thinking that this is very doable. I'm lookin at these cross shafts and thinking the machine work to do the caster slugs is very possible also. I think I need to get my hands on some caster slugs to be sure though, Looks like a quick call to CV products is in order.
Ya, I know what your thinkin. Why spend the money to take a chance on something that may or may not work, right. Well for me it's all about the "outside the box thing". I'm weired that way :D. Gotta try something new.
Your feed back is a big help and greatly appreciated. I'm diggin this colaboration of the minds. Keep it commin.

Yes, if you move the UBJ outwards about .305" that will yield approximately a 2 degree camber change with an 8.75" tall spindle. If you're going to mod I would try to push the UBJ as far to the outside as you could; you can always correct that with shims. If you don't get them offset enough you might still not achieve a reasonable amount of camber when you align the car.

As far as the caster slugs, that should be no problem at all.

I thought of modding my GW uppers too-- but I still figure I can ebay them for what I paid for the SPC arms and it will be a wash and in the end I'll have a functionally superior arm in terms of alignment capability.

All right guys,,, I am in the same boat so here is my question. I totaled up how much I payed for my upper GW stuff. CNR 40- 1 w/t del alum's, Wilwood big 4 piston calipers and 13 in slotted / plated roters = $3195.00 never used. How much of a discount should I put on these to move them and get the right stuff. ? To get the right stuff is about $3200.00

Even new and not used you're probably going to be lucky to get 75% of the original purchase price. Used, probably around 50%-60%.

However... here's what I would do:

Market and sell the brakes to a B-body or 2nd Gen F-body owner... they're a direct bolt on for those cars and will be a much easier sale.

List the arms separately on ebay or similar. There is so much info on the B-body negatives now on this board you'll probably have zero luck in the classifieds here on this site... I know this firsthand.

Just FYI, before my buyer backed out I had an offer of $1500 for my Baer's and GW uppers as a package. The Baers new were $1740 and the GW uppers were $700, so about 62% of the original purchase price. :(

Thanks Troy

Mike,

Where did you get those spring adjustors ? Part # if possible. Thanks

http://i189.photobucket.com/albums/z189/F1Speed/DSC00849.jpg

Adjusters are from here... have your wallet ready.

http://www.budzter.com/

If you can use 5" springs with no pigtails in the rear, then you can just use weightjack adjusters from speedway motors. I just welded the 1 1/8" nut to a plate and attached that to the stock spring location.

If you can use 5" springs with no pigtails in the rear, then you can just use weightjack adjusters from speedway motors. I just welded the 1 1/8" nut to a plate and attached that to the stock spring location.

This is the cheaper solution that is just as functional-- although not as pretty as the Budzter adjusters.

I bought a set of the speedway adjusters to do just as you described but I ended up liking the ride height with the 11" single pigtail springs against the factory spring perch... no adjusters needed.

If you guys really wanna think outside the box, we need to start working on mark and spohn to come out with the widetrack lower control arms.

Mark, follow the link that Troy posted. Kinda pricey but they sure do work smooth. One hand on the ratchet with minimal effort to turn with the weight of the car on the springs. To me they were well worth it.

If you guys really wanna think outside the box, we need to start working on mark and spohn to come out with the widetrack lower control arms.

Hehehe... We sure kicked that idea around a while back. I'd still love to do it, but given what I see to be a very small market for it the price would be prohibitive. I can't see that many guys wanting to swap EVERYTHING on the front end and then having a late-model looking wheel. I see SOOOO many guys wanting "as deep of a dish as possible" I can't see many people wanting to run a late model style wheel where backspacing is 2/3-3/4 of the wheel's width... even if it does yield a substantial reduction in scrub radius.

Still, the scrub on these cars isn't too bad stock, certainly not to the point of excessive wheel kickback. You can throw all the money you want at it but in the end you still need to learn to drive the thing. :)

That is very true Troy I have a long ways to go before mine will be seeing the track but I bet I am even further away from being a good enough driver for the scrub radius to effect my track times. I do remember the topic coming up a while back and it definitely sounds good on paper but cost and limited demand as you mentioned would likely be unsurmountable hurdles. Makes for fun bench racing though.

So a spring with a pigtail at the bottom will not fit over this? Obviously it's upside down for our aplication.

http://www.speedwaymotors.com/eccStoreFront/product_images/2005/042-2_R.jpg

Has anyone tried installing the negative roll uppers with the offset cross shaft facing the wrong direction? GW shipped the arms to me like this and I didn't pay enough attention on the install to catch it. The car ended up coming back from the alignment shop with huge shim packs on all 4 bolts. Unless I am missing something, installing the arms with the shafts backwards should move the UCA pivot point outward. Does anyone have any clue whether it would move it outward enough for the AFX spindle?

-Eric

Lots of shims are good, means there is still plenty of adjustment room left.

The offset cross shafts are made to push the LCA pivots outward-- providing more clearance for shims.

If the cross shafts are facing the wrong way the offset is inwards (pulling the LCA inwards more) and reducing the amount of shims required.

I'd rather have a good amount of shims than none at all. When you're down to no shims, that means it's time to roll the frame back out on a rack.

Hey Troy, I here you guys talking about a Wide Track(longer) LCA from time to time. I do notice that the wheels on my 68 set way back in the fender and could stand to come out another 2". What is the gain suspention wise?

Thanks, Tony

Longer control arms coupled with wheels with lots of backspacing (like most late model RWD cars) means less scrub radius, scrub radius being the distance from the kingpin to the wheel/tire contact patch centerline. Thus to reduce it you need to shove the spindle in as close to the center of the wheel as possible; this means lots of backspacing to "tuck" the spindle way inside the wheel, and to maintain overall track width you need to lengthen the control arms.

Less scrub means less effort needed to turn the wheel, and also when driving over road irregularities & bumps and getting hard on the brakes there will be less "kickback" transmitted up to the steering wheel. This is part of the reason new cars have such good road manners and a neutral steering feel. However, you still want some scrub radius as 0 scrub takes away a lot of the feel as to what the front tires are really doing. I know some longtime SCCA drivers who prefer more scrub on their racecars so they get more feedback through the wheel.

Several of us kicked around the idea a while back of building longer control arms to allow running more "modern" offset wheels on the front to provide less scrub radius, along with other geometry changes such as a more direct motion ratio that would probably require frame mods to mount the shock & spring more outboard as well. But given the scrub on these cars isn't too excessive in the first place my feeling is that it would be a lot of work for not a lot of gain. You'd be better off spending the money and time doing trackdays and learning how to drive the car. Most people would be shocked just what a good driver can do with even a poorly setup car. You can do all the cool chassis stuff you want but in the end the driver is the biggest part of the equation.