Lowering Upper Control Arms on '65-'68 Mustangs

I'm sure this has been covered before, but I was thinking of lowering my upper control arms 1".
Where can I get a template to do this? And is there anything else that needs to be done other
than drilling new holes and moving it?

You'll find a template and instructions here, on Dennis Begley's excellent Shelby Site

After the arms are lowered, what alignment specs to use? I would guess Shelby specs are a good place to start but how does wheel offset affect the specs? Tire width? Seems to me wider tires would require a different camber, wouldn't different wheel offset also affect that? Factory settings have a certain amount of vagueness and understeer built in. When you put on a bigger front sway bar and add a rear sway bar in an effort to see handling improvements, how should the alignment change to maximize the improvements?

I took a look at the link and it says to change the settings for different applications. So, how does changing the specs affect the handling? What effect will changing the toe-in have? What effect will changing the caster have? What effect will changing the camber have? Also, if I use a wider tire, then the edge of the tire will have more pressure on it than the same edge on a thinner tire. It seems to me as you widen the tire, the camber would have to change. The specs given are for what size tire? As you widen the tire would all the specs have to be adjusted? Is there a site that helps explain suspension tuning? If you have understeer, what to do? If you have oversteer, what to do? Years ago I read in Hot Rod magazine, I believe, about a couple of road racers, Herb Adams and Dick Gulstrand, who had two different philosophies about handling. One said to use stiff springs and strong shocks to control them to control body lean and use relativly light sway bars. The other says to use lighter springs and shocks but use heavier sway bars to control body lean. Any thoughts on that? My Special Service (cop car) Fox chassis LTD uses poly bushings in the suspension and it feels very controllable but it does let you know about every bump and crack in the pavement. 'course it does have stiffer springs and struts and shocks than a regular car. I'm not sure I would use the poly bushings in my '66. I want it to handle better but I don't want to harsh ride poly gives you. What effect does a posi have on cornering? In my 4X4 the posi tends to cause understeer. Turn the wheel and it wants to go straight. We can use the Shelby cars as examples to set up our cars but what has been learned in the last 35 years that we can use to improve on them?


Rande, first thing is that trying to find a perfect suspension set-up for the vintage Mustang is impossible. There are no two people that would have the same requirements or driving habits. If money would be no object, just look at any new performance car, how many of them have leaf springs, how many have the same type of front suspension and steering as a 65-66, absolutely none of them. We are dealing with an antique suspension that was designed long before anyone thought about radial tires. Each person will have their own ideas on what makes it handle better, it is up to you to sort out the BS and do what works for you. I could tell you the tricks or changes I've made to my coupe, but they might not work for you. One thing I can tell you is that if you use the set up numbers that Shelby used on lowered control arms on you street car, your tires will wear very quickly.

Mike {kcode}

You're right about the tire wear, it's definitely a consideration. But if your main interest is handling, lowering the upper A-arm works. Note that there are some aftermarket springs that should NOT be used with lowered A-arms. I see you found Dennis's site; I'd forgotten he has the front end dope on-line. If your springs are tired install some new ones while you're in there, and a set of Gabriel adjustable shocks on all 4 corners (set in the middle) wouldn't be a bad idea.


Yikes, George, you say there are some aftermarket springs that should NOT be used with lowered A arms. Can you explain?

My car is 12,000 miles away getting a paint job (while I freeze my nuts off in England), and since the engine is coming out, I asked my mechanic to lower the A arms and find some suitable new front springs. What kind of disaster am I looking at if he chooses the wrong springs? (As you may know, I'm looking at popping in a 429, but for the time being, they only have to handle a 351W.)
Simon {Fastback68}

I realize that I will have to do some experimenting to get the ride and handling I am looking for. kcode's point is understood. I am not looking for someone to give me a set of magic numbers. What I am looking for is some guidelines to work with. My question about tire width and camber settings for instance. Seems to me a wider tire needs a different camber setting than a narrow tire. Perhaps front alignment isn't as critical as I may be thinking it is? Perhaps on a street car, basic settings are just fine. Lots of time spent experimenting would not show much improvement in the real world although on a dedicated track car it would. What do you guys think? What is it about the Shelby settings that causes the accellerated tire wear? Is there a solution for that?


The Shelby specs are for hard road course driving, hard lefts and hard rights. If this is the purpose of the car use the specs. When I made this change about 5 years ago, the alignment mechanic laughed at the caster/camber specs. What he set mine at was zero degree on both. After about 20,000 miles with 15 x 7 inch rims and 215-65 radial tires, the inside tread is showing some wear. But, the car handles perfectly on the street and interstate highway and the Kentucky backroads. George won't agree with this, but, I'm also running the 620 front springs and 1 1/8 sway bar and KYB gas shocks. The ride is very firm almost stiff, but thats what I wanted. One other suggestion, make the rear suspension match the front. If you put poly bushings up front, do the same to the rear. Good luck.....

Mike {kcode}

Hey Kcode, run what you brung. If you like to rattle your fillings, go for it! I'm not sure what sized sway bar or spring rate my '67 Shelby 350GT has, but it's a little mushy compared with my ex C type Jag, Lotus 11, and '73 911 Targa.


I just finished installing my suspension kit from Mustangs Unlimited, 620's and 1" sway bar on front and 4 1/2" leafs with the 3/4" bar in back. In the front I used all urethane except for the lower control arms and strut rods, rubber in the rear springs, urethane for the sway bar. Boy, what a night and day improvement that is. The parts all fit well and look good. Anyway, my alignment specs are the way I wanted .3 degree - camber 2.5 degrees + camber and 1/16 inch toe in. I used - camber so the tires don't "roll under" in the corners.

As an 8 year alignment man I don't agree with the 0 0 settings. Sure the car will track straight and the tires are bound to wear with these settings, but how about in the corners? I would think it would be prone to bump steer, and, at the least, the toe out in turns will cause problems. Take some of the german cars made for the autobahn. They can run as much as 4-5 degrees of caster to a point. A Saab has this engineered into its design. (look at how the strut is angled)

Yes, the wider the tire the more tire wear you will get. With camber and toe, the wider the tire, the less you will want. I don't recomed 0 toe or camber, though. You need some toe in to make up for the natural pull out of the tires when driving. Same goes for camber under acceleration or heavy braking. These angels will change dramaticly. The last consideration is driver weight. I have seen cars that I had to set the align to PULL to make up for a very heavy driver. If one side is weighted down, the effect is like having a broken spring; one side will shift to the negative and the other side will shift to the positive. This is in case of major weight transfer. With new springs, a 260 pound driver shouldn't have any problems with this. (thats why I changed all mine to the 620's. lol)
Well, I'll stop now.
Joe {Brockjoe}

To add one more thing, don't forget about air pressure. This will have a big effect on wear and handling.

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