Early Mustang Suspension

[Huskinhano]

What are you looking to do with the Mustang? True they have crappy geometry but some really simple stuff can make a big difference. The beast thing you can do is lower the UCA. This raises the roll center as well as improving camber. There's tons of stuff out there for them. On 65-66 the caster/camber is set by shims and according to Ford, the most allowable difference in shim pack thickness between front and back is 1/16" which is good for either 2/3* camber or 1* caster and the struts are not adjustable. So you can see theoretically you're doomed. 67 & up caster is set by the strut and camber by the eccentric on the lower control arm bolt. Here's what I've installed on my 66.









I've also installed roller spring perches.



I'm in the process of installing a camber kit.



I've been sourcing my parts from here http://www.streetortrack.com/ This stuff is very high quality and it's function first with Street or Track. I've been trying to get the owner, Shaun, over here on BS. Great guy met him a few times. He'll set you straight.

[cantvalve16]

I plan to do all sorts of stuff with this car with it's roots being a totally daily driveable street car. Drag racing, autocross, road course, Pikes Peak, land speed, light off road rally, and Drag Week are some of the things I want to be able to do at an entry level. Most of all, I want to be able to throw a bag in the trunk and take off for the weekend for any event of my choosing. I hope to not have it on a trailer unless it's broken.

That said, I don't expect greatness at anything I put it through. I just expect completion at anything I do with it. It needs to be easy to get parts for and stop, accelerate, handle, and steer better than it did from the factory. Most of my goals can be met with improved stock style parts. The one thing that bothers me about these cars is the large on center dead spot in the steering. This car has almost 3 inches of play with the stock steering wheel before any output from the pitman arm happens. That has to go.

Those (in a nutshell) are my expectations for this car. I don't expect to meet those expectations all at once, though I do intend to sneak up on them.

[Loren]

Gail's '67 Mustang got re-built in the nineties, I kinda picked the normal/obvious things (to me) to tweak in the suspension (which already had stock disc brakes). I brought the upper control arm inner pivots down 5/8" or so which is as easy as drilling a few holes, (which helps the camber), lowered it 1 1/2" or so by cutting the f. springs (which also helps camber, stiffens the rate plus lowers the roll center just a bit), cut the ends off the a-arms and re-welded them on rearward for 5 degrees caster, used urethane bushings all around and finally installed whatever nice fat front sway bar was in the Mustang catalog as well as sticking the battery in the trunk. At the rear I just used an adjustable sway bar to dial in over/understeer from that point. I forget what shocks but they were something upgraded just a bit, and oh-yeah, widened a set of stock GT rims to 7" which still makes for a pretty little tire but was an improvement.

The thing handled great, it was no race car but a pleasure to drive in the canyons. Really, the most awful stuff about an early Mustang does not show up if you just have enough sway bar and shock in there, and fix the camber and caster. I would not automatically pull it out and change to anything more modern...

Except for the steering. Sucks, sucks, sucks. Did I mention it SUCKED? That part, after paying a shop good money to go through it, I got so sick of I tore it all out and in the days before kits were available, did most of the work to put in a rack & pinion but never finished it due to other things and it's all sat and rusted ever since. I just don't believe how crappy Ford would let their steering be in those days. If I ever drag that car out again and fix it back up, it'll be the steering I re-do first.

[BKBridges]

Loren,
That sounds like the program Im going to put my 68 cougar through. As Im not a suspension guy I got a copy of the Boss 302 Chassis modification book to help me out. They were not real clear on the a arm mods other than to say use the boss 429 stuff...any pics of your a arms around?
BKB

[BBR]

Isn't there a kit available to convert an early mustang to a modified mcpherson strut and rack n pinion steering ala fox body?

Edit.... AJE offers one.

[JeffMcKC]

I have a guy trying one of AJE's right now they did have a LOT of fitment issues, they now say thats fixed.

[BBR]

Here's a thread on the AJE.

http://www.yellowbullet.com/forum/showthread.php?t=154733

[milner351]

If you're going that far why not go M2 and remove the shock towers completely (I'm no suspension expert)

[BBR]

RRS has one too.... but pricey I imagine.

http://www.rrs-online.com/

[Loren]

BK, here's some pretty ratty pics of pretty ratty car...it's been sitting for fifteen years at-least. (in '92 it got second-in-class at a local car show, but that was a long time ago.) You can't see the a-arm mods, except for sway bar brackets where the upper was used to mount to instead of the lower as was in the kit. Others show machined rr sway bar w/ clamp set on the end for least roll stiffness, which is what worked, the rest of the clamp set is on a fabricated bracket hidden behind frame. There is some hardware for the abandoned-project rack-pinion conversion, an "export brace" in the engine compartment which now serves as a freeway for rodents and a shot showing lowered upper-a-arm holes, you can't go very far down on those because of reinforcement on the other side which you'd be moving out of. All the crap on the roof is to keep the rain out of the cracked vinyl roof cover but I'm afraid it's too late...I keep watching for a good '67-68 roof now which I'll have to weld on there if we ever want to fix up this car again.

[Huskinhano]

Here's some pixs of my suspension project.






This photo shows the bottom of my home made spring compressor, bottom of an old shock welded to 5/8" threaded rod


Top half of spring compressor is unistrut, wheel bearing, 1" electrical connector lock nut (needed spacer for bearing not to rub on 5/8 nut.


Cheapy HF balljoint spreader that worked like a charm!

Yeah, it becomes a viscous cycle! My original plans were to lower the UCA 1" down, 1/8" back, use the roller spring perches and adjustable struts and call in a day. What happened? Good question. Factory specs are -1* to +1* caster and +1/2* to 0* camber. Wow great specs, huh? A friend of mine who use to road race his 66 Mustang and knew his suspension told me radial tire run like the tires you see in cartoons, oval shape, that moves the contact patch even farther back, reducing caster even more from the original bias ply tire. When you set the caster/camber with shims, according to the shp manual the two stacks should not vary more then 1/16" which equals 2/3* camber or 1* caster, keep in mind the struts are not adjustable! Also adding shims to gain caster has the undesirable effect of adding + camber because it's swinging the UCA on an arc, moving the ball joint out as well as rear ward. On the Mustang forum I hang out on I've read so many times of guys who can'r seem to get much more caster even when they make adjustments to the struts, some times the tire hit the tip of the fender. Some guys have tried to gain caster by readjusting or altering the UCA shaft by not centering the UCA on the shaft but off setting it with limited results. So with this in mind I decided it was time for aftermarket UCA. I've met Shaun a few times and saw his new UCA he had on display at the Ford Carlisle show. They were absolutely beautiful! When he had them in production, he made me an offer I couldn't refuse so I bought them. No regrets even though it wasn't really in the budget.

When I had the suspension together, I bought a caster/camber gauge because I want to try doing my own alignments plus I can only imagine trying to tell some kid who's use to working on strut type cars how to do it and get what I want. I found I had a +1/8* camber on one side and + 7/8* camber on the other side. I need the camber kit which I posted and in the process of installing that now. My UCA and LCA are Ford service parts that have very low miles on them, probably less then 5,000 miles. When I got the lower control arm bolts out and swung the arms out, the bushing on the right side looked great, no dry rot or anything. The left side looked like it went through a meat grinder! All torn up and the sleeve was elongated. This is another common problem on these cars. With worn bushings, camber is all over the place. I'm going to be buying Shaun's LCA because he uses a bearing.

Replacement suspension parts are usually off shore and of poor quality and fitment, another reason to buy the parts I did. Just subtract the cost of crap off shore parts and it makes it even more of a bargain. Once done, I will have all the adjustablity that I'll ever need and can easily rebuild them down the road as well. I'm also going to keep my drag link system. One of the best things I ever did was remove the factory PS crap. Borgeson makes a nice integral box based off an Isuzu box or go Flaming river for a manual box. I'm keeping a 289/302 because it's all the motor I'll need in this car plus they are light, about 480 pounds, less with aluminum parts. I'm not sold on R&P conversions from what I have read. The big problem in conversions is reduced turning radius a lot of times and increased effort if manual. Also bump steer become an issue. The basic reason is this. On a drag link, Ackerman is built into the angle of the tie rod arms on the spindles. R&P, the geometry is totally different and Ackerman is in the linkage ngbasically so the tie rod arms are more perpendicular to the axle center line. Putting R&P on a drag link spindle gives kind of a double dose and can cause bump steer issues. Ackerman is basically increased toe out in a turn.

I'd strongly suggest going to www.vintage-mustang.com and follow guys like Shaun, GT289, Silverbluebp, supershifter2 and a couple others. These are guys who know their Mustang stuff and road race. GT289 is an ex Global West engineer. All of these guys will tell you not to run a rear bar either. In conclusion let me stress I'm not an expert in this area or have a lot of experience. What I have tried to do is learn as much as I could, ask a lot of question so I have some footing before I attempted any suspension mods on my car so I don't find myself in a WTF moment. I'll be doing this all myself since I really don't know any one who can come over and help out if I totally F this up. Basically Brian, I think I'm just a few steps down the road from you on this topic and trying to pass onlong what I have found.

Some of my comment might seem to be contrary to Loren, there not meant to be. I only know Loren from his post and from what little I know, Loren knows his stuff! Loren is doing his own work, he knows exactly what he's looking for and how to fine tune results to his preferences. What I am saying is more of a fail safe mode for noobs like me. 67 and up Mustangs had big changes done to the front suspension. The UCA location was changed. The LCA was lengthened, caster was set by the strut and camber was set by an eccentric on the LCA. I've read that this set up from the factory was akin to the 65-66 Mustangs with the UCA relocated.

[Huskinhano]

Just for shits and giggles

Here's Shaun's car. He's currently doing up grades. http://forums.vintage-mustang.com/tr...-66-coupe.html

SilverblueBP's car http://www.cardomain.com/ride/667160/1966-ford-mustang/

Here's his car on the track, his suspension very basic. Relocated stock UCA, 1" down 1" back 1/8", 1" front bar, no rear bar, Konis, and 12" x 1.25" front disc. I was in converstion with him. Not sure if it was this event but he was with a Porsche Audi club. They were totally shocked at how well his car worked with basically stock parts.

[Loren]

Some of my comment might seem to be contrary...

No, you're doing fine. Especially if you get your steering worked out.

A '65-66 will take more u.c.a. inner-pivot lowering than a '67, where the spring tower stampings are a little different. That's a good thing and it looks like you got it right.

Re: Rack and pinion, I couldn't find a narrow-enough rear-steer rack at the time, I had to do the best I could ('80s GM front-drive mid-size) and then change the lower control arm pivot location/length to match that, which shortened it up quite a bit but not too much, and also shorten/sleeve the rack tie rods. So no bump steer, anyhow. As for Ackermann, I've never regarded that as vital-important other than for parking lots, if you're at least reasonable, radials usually have enough slip angle that anything close will do.

The kits you can buy now are probably a better deal, but all-in-all I would pull my setup back out and return it to stock IF there could be a decent steering box in there, meaning tight with the right ratio and power assist.

For rear sway bars, as you saw, I had it on the loosest setting and I'm betting also that with stiffer leaf-spring bushings it would be unneccesary altogether. For a light car with leaf springs, why not use the leafs for roll stiffness and eliminate an extra part if you can?

Anyhow, early Mustangs are fun and it doesn't take much power for one to haul butt.

[Huskinhano]

Good stuff Loren, thanks at least I know I'm on the right track. I agree with you on the Ackerman. I was just using it since most people know what it is. I did notice you had it on the loosest setting and you're right about bushings. So much goes on with leaf springs like you say. Just changing front bushing (in the leaf spring) stiffness has a anti roll effect as well as the leaf springs. Most people don't realize as the car rolls and the axle is no longer parallel to the body but at an angle, it twists the leaf spring much like a torsion bar adding roll resistance or anti roll. This is why on leaf sprung rear axles cars, you'll either a very small or no rear bar compared to a coil sprung rear axle. Same goes for Panhard bars. People think they just keep the axle from sliding back and forth with out ever realizing exactly what it's really doing, such as counter acting drive line torque for one.

Another interesting thing you can do to the UCA is to move the spring perch location out 1/2". This improves motion ratio as well as making the stock spring act as if it's stiffer but providing a soft ride. Closer to the center of the car, the stiffer the spring needs to be to maintain the same roll resistance. Move 'em out, keep a soft spring for comfy driving while keeping the car flat.

[cantvalve16]

Guys, I am loving all the tech in this thread. There are things elaborated on here that I never really understood. I have had a few '60's Fords with these suspensions and done a couple of mods in the way of Shelby/Arning drop, big sway bar, and stiffer bushings. You guys are getting into the "why" of how early Mustang suspension doesn't work well and how to correct it. Lots of things to think about as I drive around during work. Thanks, all.