Shelby drop-Negative wedge camber corrector kit needed?

I've read somewhere that in order to do the Shelby drop "properly" a negative wedge camber corrector kit like the one advertised at this link ( http://www.drgas.com/promotor/products.html ) should be used. I would love to hear from anyone who has done the drop on a Maverick, with or without the kit, as to how effective this modification is in improving Maverick handling, and if there are any problems associated with doing it. Any wisdom/experience you can share with us would be appreciated by a number of board members, I'm sure. Thanks in advance to anyone who can contribute. John B.

 

The Shelby upper control arm drop was only 1" & didn't require a negative wedge kit as the ball joints would not reach bind when cornering. The negative wedge kit is to prevent upper ball joint bind when lowering the upper control arms 1 1/2" to 1 3/4". This much drop dramatically increase corner capabilties, but the balljoint negative wedge kit must be used. Additionally, you should also use the bump steer kit as this will also be altered by dropping the lower control arms. With that said, the Maverick presents a hole new set of problems. The shock tower housing on the Maverick is slightly narrower than the Mustang & the upper control arm doesn't have enough clearance when moving it down even one inch. I had to heat up the area on each side of the tower with a torch & peen it from the inside out to achieve enough clearance for the control arm to move freely at 1 inch lower. I've seen some people cut holes in the towers(like you see for lube fitting access) to achieve the necessary clearance. If you want to retain the lube fittings & their use, it must be peened out even further. Both methods look unsightly, unless an actual piece is fabricated. I elect to smooth out the engine bay side with bondo to try & hide the damage I created from peening the towers. Really the wrong way to do it, but it looks very good. Interesting enough, I found the same problem with my 68 Torino 390 GT fastback as my Maverick when lowering the upper control arms. Hope this helps

 

GS,

I feel better about my beatin' hell outta my towers now to get the uppers to swing full stroke.

I also lowered mine 1" and had to address the grease zirt issue too. I opened the hole up even more (looks like sh*t, but it's a drag only car). I may have found yet another use for Duct Tape!

I was hesitant to cut even more sheet metal as I've done the shock-tower mod also. I'm going to HAVE to make a shock-tower to shock-tower brace (Monte Carlo?) for fear of the front end collapsing on me.

Someone on here made one for an E.F.I. I believe?

R

 

There is another option. Moog makes a shaft and bushing kit as a retrofit for older Fords. This replaces the standard metal/metal bushing with a rubber bushing like is used on Brand-X car.

The advantages are...

1. No need to lubricate the bushings so no need for grease zerks.
2. The shaft is now 1/2" narrower on each side.

Using these bushings allows you to drop the mounting holes 1" with no side to side clearance issues at all. The one change I have done is to grind out notches in the sheetmetal at the front and rear of the "dirt trap" below the upper A-arm. This way, the full range of motion is still possible.

From Rockauto.com the part number is:

Moog Part # K8233
(Upper Control Arm Shaft Kit) Problem Solver, Rubber Bushing Type Shaft Kit;

Note: After this kit is installed, threaded shaft cannot be reinstalled in the future as this bushing is pressed in and will ruin the threads in the control arm.

I have installed these on my '70 and dropped the upper control arms by 1" using a template for a 69/70 mustang that I downloaded from the net. Everything seems to fit fine with no interference.

Now all we need are greaseable spring perches with urathane bushings to get rid of that annoying squeak that almost always seems to start right after you reassemble the entire front end.....

 

Hey guys I did the Shelby Drop on our Mav. I used standard replacement cross shafts and PST bushings. Now I have been trying to get the front end alignment close and I am having trouble with it. The least amount of camber I can get out of each side is 1 degree positive. I am aiming for around 1/2 degree negative and can't get close. I tried to put a priliminary alignment on it before I put the front springs in. The camber was 1 deg. pos. then and is still the same with the spings in and some of the car assembled. It doesn't appear that it is going to fix itself. Is there something I am missing to get more negative camber out of it? Thanks

Greg

 

I've also made the Shelby mod; first it didn't lower my front end that I could see. Second I cut two rounds out of my coil springs and that lowered my front end. Use a saw not a hot wrench!!

My car is mainly for drag but I drive it locally to some of the classic car shows (just the ones with muscle cars) and I've never had any problems with my ball joints. This is one thing I keep a close eye on because of the high speeds when racing. I did have the front end aligned after the mod and I give the tech the alignment specs I wanted the car to have, from the mustang web site. Is the negative wedge camber corrector kit needed? I’m not sure, I don’t use it but it probable wouldn’t be a bad thing to have.

I hope this helps.

Terry Gates
AKA Bossmav

 

This is from the Mustang web site on how to lower the front end of your Mustang. Here they never say anything about the negative wedge camber corrector kit.
I hope this helps.

Bossmav



One of the Shelby American tricks on the early GT 350s was to lower the body. The factory did this modification to all 65's and the 66's up to and including #252. This was Ford engineer Klaus Arning's idea. Klaus also developed the suspensions for the 427 Cobras and the GT 40. He happened on to the idea of lowering the control arms while experimenting with an independent suspension rear end for the 1964 Mustang. Ford vetoed the extra cost of an independent rear suspension in the Mustang but passed the idea of lowering the car on to Shelby American.

By dropping the height of the body, the center of gravity is lowered. This helped the handling of the car by reducing the body roll by 8% during cornering.

To do this modifications you need:

The lowering template full size included here
A lug wrench, a jack, some jack stands (you'll need to raise the front of the car to remove the wheels.)
A one-inch socket to remove the shock absorbers
A spring compressor
A three-quarter inch wrench to remove the control arm mounting nuts
An electric drill and a 17/32" bit (you might need a smaller bit to start the hole in the shock towers.)
A couple of cement blocks (or another set of jack stands) to support the rotor hub assembly.
This will take you at least 4 hours to do this job. Renting a spring compressor will make the job a lot easier.

Steps:

Use the jack stands to support the front end. Remove the wheels and shock absorbers
Compress the front springs. You don't have to remove them although if you do it will give you more room to work
Use the cement block to support the brake rotor or lower control arm.
Unbolt the upper control arm from inside the engine compartment. Save the original shims (65 & 66 only).
Swing the upper control arm assembly, rotor and spindle assembly to the side. Don't strain the brake line.
Using the template from this article and trim out the holes.
Secure the template in place on the car using the original bolts in the original holes using 1/2 inch bolts. Note that this template is drawn for the driver's side. Flip it around to use on the passenger side.
Mark the center of the new holes using the template.
Drill the new holes. It probably will work best to drill a smaller hole in the center then work up in two or three steps to the 17/32" hole.
Install the upper control arms in the new mounting holes. Be sure to replace the alignment shims in the 65-66 models in the reverse order that you removed them. (Remove an even thickness of about 1/8"-1/4" of shims from each position to compensate for the increased positive camber affected by the lowering.)
Reassemble the front suspension by reversing the way you took it apart.
You'll have to have the front end of the car re-aligned. Get it to a frame shop as soon as you can to save on excessive tire wear. If you have wide tires on the front they may rub the fender now do to excessive positive camber. You can help alleviate that by taking out more shims in the 65-66 or adjusting the lower control arm inner pivot on the 67-70 camber adjusting cam. You can also use spring boosters to raise the front end off the tires or install smaller tires. Using spring boosters kinda defeats the purpose of lowering the car though. If you use smaller tires make sure you have the tires and rims on the car you are going to use when you have the front end aligned. (and take out the spring boosters.)

Alignment specs for lowered Mustangs (only):

Chuck Cantwell, Shelby American GT 350 project engineer recommended 2 degrees positive caster, 1 degree negative camber and 1/8 " toe in for all years of Shelby Mustangs. You can play with settings for different applications.

Here are the specifications for dropping the front end. This is a template to use to drill the new holes. This is a compressed version. Use the view image in your browser to expand this picture to full size before you print it off.

 

Sorry about the image being so big it is already full size, if you need it just print it the way it is.

Bossmav

 

Thanks guys for the input. I did use that template and followed all of those directions to drill the new holes. As I understand it, ball joint bind is not a problem with a 1" drop. That is the reason, I think, for the negative wedge kit. Does this kit also provide you with more possible negative camber? Camber is my real problem right now but it may be solving itself after all. I guess I wasn't prepared for how much this light weight car can flex when more weight is added to it. We put the engine in Sat. and the camber is just about 0 now. I am going to loosen the adjustment screws and rool the car over a bump in our driveway a few times. Maybe then it will settle down. Thanks again guys, I still have a lot tio learn and this board helps a lot.

Greg

 

Wups. I guess I should have said "Thanks Terry for your help." Sorry about that. Good luck and God bless Terry.

Greg

 

Are you trying to align the frontend as your car looks in the pic? If so, you need a ton more weight on the car to get an accurate adjustment. I'd wait to align the frontend until everything is in place on the car. Negative wedge kits do not effect your camber alignment at all. Typically they are designed to prevent upper ball joint bind from relocating the upper control arms more than one inch. A lot of the Mustang guys are now relocating the upper control arms 1 1/2 to 1 3/4 inches & the upper ball joint will reach bind during cornering & then break the control arm or pull the ball joint out of its mounting. The 1 inch drop was never used with a negative wedge kit when the Shelbys originally dropped their upper control arms. I suppose if you took a car & set it up with 2 or 3 degrees negative camber with the 1 inch drop, you could probably reach ball joint bind at that point. Hope this helps.

 

Thanks GS. I have in the past with some fuul frame brand "C" cars been able to aligne the front end while building it. I set the car framw at ride height and had the front springs removed. I used a spindle mounted circle track bubble alignment tool to get the caster and camber pretty close. Then I would finish assembling the car and tweak the alignment a little if needed.

This car is a different animal. You are right about the weight. I worked on the alignment before the doors , fenders, or engine were installed. Couldn't get anywhere close to anything with negative camber. Sat. we put the doors, engine, and fenders on and I noticed the camber change after we moved the car. I thought my eyes were playing tricks on me so I got out the carpenters square. Sure enough, it had moved closer to zero. The camber bolts are already tightened and I am going to loosen them and see if it moves some more. The question I have is, with all of the added weight are the tops of the shock towers rolling inward slightly and thus giving me more negative camber? If that is true I can certainly see a Monte Carlo bar in this cars future. Thanks again GS.

Greg

 

I'm sure there is slight shock tower movement with the added weight, but the real change is due to the ride heighth change from the added weight. The arc geometry changes as the suspension goes thru its' travel span. This holds true for most cars, whether brand A, B or C. Hope this helps.

 

I agree GS. What you are talking about is bump steer, right? I try to minimize that by getting evething at ride heigth initially. The alignment is pretty much a compromise anyway due to bumpsteer, but we do the best that we can.

The preliminary alignment is easier to do when all of the other stuff isn't in the way. Then when I do put everything on hopefully it will be still close. When I was a lot younger and more enegetic I would build a car and then drive it with tires sqealing to the alignment shop. Everything would be WAY off and sometimes the results I got back were not what I had in mind. Now I try to control more of the process myself to hopefully get better results.

 

OK, I am swapping out the power steering to manual, plus I just bought the plastic caps that go on the top of my front coil springs. While I am in there, I am thinking about doing this "Shelby drop". Will 215 or 225 wide tires be a problem?

Is this worth all the work?