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View Full Version : SPC / SC&C Adjustable Upper Control Arms - Droop Stop?



TheBandit
07-15-2011, 06:51 AM
I am interested in the SPC / SC&C adjustable upper arms for my '70 Nova, but I am a bit concerned that they lack a droop stop. I realize droop stops are a bit less important than bump stops, but to protect shocks from over extension and soften the blow of (rare) offloading of the tire, I'm curious if anyone has added them somehow.

I'm also curious how difficult these are to adjust when you're aligning the car. Do the adjustment sleeves turn easily when you have the weight on the tires? Can you access them easily with the inner fenders and tires on?

Here is a picture of the arms from John's Blue Bomb thread:

https://static1.pt-content.com/images/pt/2010/06/0505002056-1.jpg

Thanks for any feedback or comments.

TheBandit
07-15-2011, 07:01 AM
Found a little info searching around. This thread on Team Camaro shows some limiter ideas: http://www.camaros.net/forums/showthread.php?t=149211

https://static1.pt-content.com/images/pt/2011/07/attachmentphpattachmentid9097d1232292577-1.jpg

https://static1.pt-content.com/images/noimg.gif

John Wright
07-15-2011, 07:09 AM
I'm also curious how difficult these are to adjust when you're aligning the car. Do the adjustment sleeves turn easily when you have the weight on the tires? Can you access them easily with the inner fenders and tires on?


I took my sleeves apart and put a liberal coat of antiseize on the threads....I can back off the jam nuts and turn the sleeves very easily with a short wrench with the car sitting on the ground....jack it up so the wheel is hanging and I can turn them by hand.

Randy67
07-15-2011, 08:35 AM
I didn't have any limiters on my El Camino and never had any issues, even with 2+ seasons of autox. The shocks stopped droop just before the upper control arm would hit the frame. Is it hard on the shocks? I don't know for sure, but on A-bodies like Chevelles the rear shocks are the limiters for suspension travel and I haven't seen anyone have problems with them (other than using air shocks, but that's a different problem).

John Wright
07-15-2011, 08:46 AM
A-bodies like Chevelles the rear shocks are the limiters for suspension travel .2 gen camaros are the same way...to get the rear suspension to full droop, you have to unbolt the shocks first.

Steven
07-15-2011, 11:25 AM
no problems on the monte, the usual answer is to call marcus at SC&C and discuss it with him.

knucklebusted
07-15-2011, 05:47 PM
I had those for 4 or 5 years and they are easily adjusted. They give great header clearance since all the shims are gone. The whole droop thing bothered me, too, despite the better geometry they provided. My arms had the aluminum adjusters and I was more fearful of them getting damaged than the regular ones. I finally bought a set of tubular upper/lower arms and swapped them a month ago. The new arms aligned quite well but the shims do encroach a bit more. I looked at the limiter straps but decided against them for my application.

ROBS6T8
07-18-2011, 07:08 AM
I took my sleeves apart and put a liberal coat of antiseize on the threads....I can back off the jam nuts and turn the sleeves very easily with a short wrench with the car sitting on the ground....jack it up so the wheel is hanging and I can turn them by hand.

Great idea John. I'm assuming you did this before installation? I wonder how difficult it would be with them already installed?

John Wright
07-18-2011, 07:18 AM
Mine are heavier than they need to be.....I have the steel sleeves, I should have purchased the aluminum hex sleeves, but money was tight and I improvised and welded on a large hex nut.

https://static1.pt-content.com/images/pt/2009/10/MVC004F-1.jpg

https://static1.pt-content.com/images/pt/2009/10/MVC003F-1.jpg

TheBandit
07-18-2011, 07:25 AM
I called Marcus and he was kind enough to chat with me for about an hour about different options for the 1st gen Camaro suspension. It was a very interesting conversation and I appreciate him taking his time to walk through things with me.

With regards to droop stops, Marcus initially said the droop travel would be limited by the shocks. He pointed out that the rear suspension is shock limited and they should be able to handle it. At the time of the conversation, I failed to think through the differences front & rear, especially the mounting position of the shocks and the increased spring forces at that position. Whether or not that's significant compared to the weight of a rear axle & springs or the dynamic loading, I'm not sure. As Marcus and I continued our conversation, we came to the question of the Guldstrand mod. I've already modified my towers to do this and Marcus proposed that I have lost precious suspension travel as a result. This idea suggests to me that the shocks would not be the limiter, but rather the upper control arms hitting their stops. In talking with Marcus further, he said the SPC control arm may contact the frame, but other than losing down travel, this is not something to worry about because it will happen very rarely and will not be under significant load.

Marcus's recommendation to me was to use his Stage 1 arms which include a taller ("medium height") balljoint in conjunction with the Guldstrand mod. He gave a few reasons for this; increasing camber gain, regaining the downtravel I've lost with the G-mod and situating the balljoint at a more appropriate operating angle. My biggest take-away from our conversation was this: he said that the numbers I've seen floating around on the Internet for camber gain with the G-mod are not correct. I can only assume he's referring to the measurment's David Pozzi has on his website. Macus said that with the G-mod and no other changes the camber gain will be in the neighborhood of -0.1 deg/in from ride height (Pozzi's site shows -0.7deg/in from ride) and with the SC&C "medium height" balljoints the camber gain would be closer to -0.75 deg/in from ride height. He also added the disclaimer that this will vary from car to car and especially depends on where the ride height is set. Marcus insisted the numbers on the 'net are just plain wrong.

After I got off the phone I measured my factory arms to investigate how much travel I've lost with the G-mod. They are currenty limited by the bumpstops. The distance from the cross shaft to the bumpstop is about 7" and the distance from the bumpstop to the balljoint is about 3". This is a lever ratio of 7:3. I moved my cross shaft down 7/8" (G-mod), so that amounts to a reduced travel of 3/8" at the outter balljoint. I'm not sure exactly what the distance is to the center of the tire, but my guess is I'm not losing much more than 1/2" of ride travel using this modification. To me that doesn't seem like anything to worry about, especially considering that I will lower the car by approxitely 2".

So in deciding on these arms and whether or not taller balljoints would be appropriate, I think there is really just one more thing to look into: what the actual camber numbers are with my suspension post G-mod. I'd like to see if Marcus's claim is correct and if a taller balljoint really would be a better option. I should be able to get a crude measurment with my current setup to verify. That's something I wanted to do anyway.

Perhaps Marcus will chime in here because I'm sure my recount of our conversation has some errors. Things are often lost in translation, memory and interpretation.

The WidowMaker
07-18-2011, 05:38 PM
i found a short energy suspension urethane piece and mounted it under the front leg of the arm. it works more as a stop when the front end is up on jack stands. the arm used to hit the frame and keep the shock from over extending, now it hits the urethane.

the car is supposed to be red, but ill change the spacers to black if it still looks odd.

https://static1.pt-content.com/images/pt/2010/10/IMG_9881-1.jpg

monteboy84
07-18-2011, 06:06 PM
Your frame makes me drool.

I have the steel sleeves on my Stage II Plus kit, wearing Mechanix gloves I was able to adjust them with weight on the wheels pretty easily, that's without anti-seize or anything of the sort, which would make it easier yet.

-matt

TheBandit
07-20-2011, 01:51 PM
Researching the SPC arms further, I stumbled on this very interesting thread and also one persons implementation of a droop stop. See post 78
http://www.nastyz28.com/forum/showthread.php?t=196734&page=6

https://static1.pt-content.com/images/pt/2011/07/UpperControlArmBumpstop001-1.jpg

smhigh
07-20-2011, 02:20 PM
I highly recommend complete dis assembly and liberally applying anti seize. I have a frozen sleeve that will require some major work to free.
I adjusted the alignment with shims for now and SC&C was nice enough to send me a free sleeve.

I like the ideas presented for the droop stops.