Vintage Mustang Forums banner

Boxed control arms vs GW/TCP control arms

4K views 22 replies 14 participants last post by  LMan 
#1 ·
Since I still can't figure out why a coilover setup would be better than a stock spring/shock setup, I've decided to look into beefing up the stock-style suspension. What setup seems to have better handling, boxed stock (or with modified ball joint angle) control arms, or the aftermarket stuff from GW and TCP. The tubular stuff they offer is buku bucks, but is it worth it?
 
#2 ·
The advantages to coilovers would be the ability to eliminate the shock towers and allow a much wider engine bay (modular, 429/460, etc).

IMHO, the tubular stuff is nice eye-candy and, if you were running 12-inch wide tires under extremely high loading would maybe be justified, but boxed OEM stuff should be just fine. The question of modifying the b.j. angle is simply one of whether you plan on changing the suspension geometry in such a way that will cause binding with the stock angle.
 
#6 ·
You could modify your stock suspension components to get the same performance as the modified stock Global West or TCP components (can't speak for the coilover conversions).

- UCA's - box and add ProMotorSportsEngineering Negative Wedge kit
- LCA's - box and add a spherical bearing
- Spring Perches - do the roller spring perch conversion
- Strut Rods - modify or home build using spherical rod ends (or buy Street or Track version)

OpenTracker didn't modify the shock towers, he modified the coil covers. This mod increases tire clearance.

If your not up to doing these modifications yourself, just send a PM to OpenTracker. I think he is going to start producing his own line of modified stock suspension components.

Tim
 
#10 ·
I saw that opentracker has successfully modified his, but I'm worried that I'd screw up the angle, or have them be slightly different.
I was too, but it's really not all that tough to get them the same. One thing I did was to add gussets on the inside underneath the UCA covering the areas where the welded cuts were. I forget which picture of Opentrackers arms showed this but I thought it was a good idea.
 
#11 ·
The coil overs reduce the binding that is put on the upper control arms. Yes the shock towers are still need but could be shaved.
The coilovers also add a ease of tuning the front end.
IE different rate shocks. Todd you ever thought of asking OT for some assistance?
From what I have seen from OPENTRACKER...you can build your own suspension. My next track style car will be set up following OT's suspension mods.
 
#14 ·
I think the advantages are better packaging and also a better motion ratio. The closer the pick up point for the spring to the wheel, the better. As you do this, it reduces the spring rate required to do the same amount of work. With the spring pick up point on the lower arm, you can get it closer to the wheel and still fit with in a compact package...at least that's what I'm thinking.

My suspension is still basically stock and I want to make improvements too. I've been doing some reading on suspension designs to get some what of an understanding. Combined with knowlege gained from years of schooling from the school of hard knocks, I think there comes a point to be brutely honest as to your intensions. As for me, yeah, I'd love to try or do open track racing...but is it really going to happen? Most likely no. With that, I don't plan on doing too much. I believe in trying to optimise the stock geometry as much as pratically can be done. To me this means either Global West UCA's or a 1" drop. My problem at this point is how the two compare on the street. I don't know. Will I notice a difference over the 1" drop? I think too much more for me will be a waste of time and money and more bling then anything else. What I don't like about the TCP, not that it's inferior to GW, it's the adjustable ends. IMO, while this is great to set alignment the big question to me is this. Just how straight and sqaure are our 40 year old cars that were mass produced and have suffered 40 years of abuse? I think it'll be too easy as an out to compensate for a tweeked unibody, to get desired, static, alignment specs. I think there's a very good chance of having 2 dimensionally different upper control arms. Suppose the guy on the rack makes the right side arm 1/2" longer then the left side to take into account that the car was min a accident. Just how well is this going to drive? It's seems as though it's going against the reason for putting quality arms in. On the other hand, I think the TCP parts are great for the guy who knows suspensions and is going to do his own work, so he can really fine tune the arms to his liking. These is my thoughts anyway. My plans for my car, aside from deciding between GW's or lowering the UCA's, are 1" front bar, export brace, Monte' Carlo bar, sub frame connectors and a good set of shocks. Presently I have KYB's. They weren't my first pick but I didn't have money at the time for the Edelbrocks that I really wanted. I also plan on running stock or very close to stock spring rates. I'm not going to a rear bar either.
 
#15 ·
yes this is a good thing. But how much time are you going to spend on the track? Range of motion and coil spring pickup are great for a road race car. Street car eh!
You can have a really decent suspension by modifiying the original suspension add some sways and good shocks.
 
#16 ·
Re: coilovers... As applejack mentioned, they have a better "motion ratio". To oversimplify, this means that the spring attachment point is near the end of the control arm. The advantage there is that if you apply a 100lb force to the tire, it only takes a 110lb spring rate to control/resist it. With the stock setup, the spring is near the middle of the (lever) arm, meaning you need a 200lb spring rate to provide the same resistance. Anytime you're dealing with "softer parts", there's less friction, and almost always less unsprung weight involved... The other big advantage of the coilover setups is adjustable ride height - can be a nice feature. All "necessary"??? Probably not, but then again, neither are 4-barrel carbs and dual exhaust. ::

Now, onto arm construction, which is really a different subject... You can modify your stockers and achieve acceptable results, depending on YOUR wants/needs/ definition of acceptable. ;) Box it, and make it strong. Then, add additional reinforcement to the spring perch mount and balljoint areas, as both are crack-prone. Now, you've got a strong arm, although it's relatively heavy. (Before someone says "but GW arms are heavy", realize the arm itself is light (unsprung weight) - the solid billet inner pivot shaft (sprung weight) is heavy. ;)) Speaking of which, your modified stamped arms still have the crappy stock inner pivot bushing - a known problem area, and the reason for 1/2 the suspension rebuilds people do. What you don't have is a shorter arm for faster negative camber gain geometry (GW arms are approx 1/2" shorter). You also have how hours of labor? I know how much $$$ I value MY time at... :shocked2: Oh, and you DID start with NEW arms, new balljoints, etc, instead of using fatigued 40 y/o metal, didn't you? ;) :paranoid:

Finally, realize that there is no "correct" answer. Everybody on here chose the components they did based on THEIR needs/wants/budgets/goals... Nobody chose the way they went because they thought it was the "2nd best choice" for them... :: My definition of great handling is not necessarily the same as the next guys... :highfive:

Finally, realize that TIRES are the biggest variable. While trick / fabricated parts are "fun", it doesn't matter what you use for suspension if you handicap yourself with skinny, hard, heavy, or soft sidewalled rubber...
 
#17 ·
*scratches head* I guess I need to do some more reading. This makes me wish I had stuck with Mechanical Engineering in college instead of switching over to computers.

When you price everything out, if you're going to go with all new stuff (other than spindles, which don't seem to be on the aftermarket yet), regardless if it's negative roll, coilover, or make it yourself, the costs are very similar. (Labor isn't free, thanks for reminding me of that GT350Clone) I guess the best way to find out is to hit the lottery and try them all ::

Thanks guys, you're the best.
 
#18 ·
*scratches head* regardless if it's negative roll, coilover, or make it yourself,
Negative roll and coil-overs are not alternatives. There are reasons for both. "Negative roll" addresses camber curve when in bump or jounce. Coil-overs are just another packaging method. You can have bad camber curve with coil-overs (which actually many coil-over equipped, specially MacPherson strut cars do have). In fact, you already have coil over your shock, coil-over means that shock and coil have same pick-up points through which the damping forces are applied.
 
#19 ·
http://home.earthlink.net/~myradpc/sitebuildercontent/sitebuilderpictures/2005upperarmodd3.jpg
http://home.earthlink.net/~myradpc/sitebuildercontent/sitebuilderpictures/2005upperarmod8.jpg

I'm working on an idea to move the spring perch forward on the upper arm to improve the motion ratio. These arms have the spring perch moved 1 1/4" from the stock location. I have not tested these on the track yet. The spring rate and shock valving has to be changed to make this work.

John
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top