A common misconception is that the Shelby/ Arning drop is to lower the car. This is actually a byproduct of lowering the upper control arm mounting points but not the intent. The main purpose of the Shelby drop is to give better camber gain of the tire when cornering hard and increase caster to give better feedback through the steering wheel. This gave the cars more responsiveness, feedback, and better handling characteristics.

Note" I repeatedly failed math in high school. I'm pretty sure they only graduated me so I'd stop breaking the woodshop equipment. That said, here's why the Arning/Shelby Drop will only lower your car by 5/8": The control arm can be lowered at the body, but not where it attaches to the spindle. You lower the arm by an inch relative to its mount to the body, but it isn't any lower at the spindle end. What lowers the car after the drop is the slight push of the spindle away rom the body and the resulting angle from the ball joint, which is roughly 5/8". So Andy's install is precisely what to expect from this mod. :thumbsup: If you want to lower your front end more than this, you'll need to look at different springs, or a coilover setup. People (including Shelby) experimented with lowering the control arm by more than one inch, but it results in premature ball joint failure from the extreme angle.

Just revisiting Andy's excellent video because of some new info and some personal experience. Kind of a long read, but it might save you some money and headaches. And, as always, "your mileage may vary". (This experience involves my '65 fastback, original T-code with a swapped 302/5-speed and all V-8 suspension components, plus GT350 steering components (manual steering box, pitman and idler arms) and 1" mid-eye leaf springs in back). With the wheels and tires all the same before and after modifications, the stock ride height (measured from the ground to the highest point of the front wheel arches) was 27". I added coilovers and adjusted the ride height to 25 1/4" (lowering the front suspension by 1 3/4" - the maximum I could get away with without bottoming out on the top of my sloped driveway and in any event probably as low as you'd want to go if you're running long-tube headers or Tri-Y headers). 25 1/4" gave me no problems in handling, no ground clearance issues over speed bumps, etc, and most importantly, no premature component wear. After a month I then added the Arning/Shelby drop (which as Andy illustrated will result in a slight lowering of about 1/2 to 5/8 of an inch, due to the UCA being pushed very slightly outward relative to the body). I compensated for that additional slight reduction in ride height by lifting the coilovers approximately the same amount. The final ride height with the corrected coilovers AND the drop remained at 25 1/4" (same as the coilovers with no Arning drop). Here's the thing - just that slight outward push combined with an already lower-than-stock height ruined my upper-ball joints after about 100 miles. I had to replace both of them, and they were both just three months old. The upside is there was enough cash in my swear jar to pay for two new joints. After that miserable task was completed I started doing some research about early Ford ball-joint failures and discovered Carroll Shelby's pit crew observed premature upper ball-joint failures in the Arning-drop GT350s. The joints were failing in about 1/3 the time of the joints in non-modified GT350s, and even resulted in a couple of near-catastrophic spindle failures during races, SO TEAM SHELBY STOPPED USING THE ARNING DROP after car #252! You will find that most of the guys racing original GT350s in today's vintage circuit are using aftermarket upper control arms with some adjustability, and already engineered with modified ball-joint mounting surfaces. You *may* be able to find a compatible "long-travel"/extreme-duty ball-joint that could do the trick (I'm thinking probably in the 4x4 community), but I haven't found one listed anywhere. So.... the bottom line is that if you're going to do the Arning/Shelby drop, only do it on a car not already lowered, and be diligent about regular ball-joint inspections. Alternately, if you're going to lower your car's spring height, don't do the Arning drop. The reality is that unless you're tracking your Mustang you're not really going to notice the handling difference gained by doing the drop, anyway.

Nice clear description of what you’re doing and why. Plus the measurements before and after. Great job.

Great video, and cool car. I’ve always loved those old fords. I have a 1968 ford fairlane 500 fastback, my dream car and I was fortunate enough to buy it earlier this year. Keep up the good work!

I’m sure other have mentioned this but the arning drop wasn’t meant to lower the vehicle ride height. Relocating the control arm gets rid of positive camber as the suspension cycles during cornering events. Due to the geometry, a byproduct of relocation results in a drop of about 5/8” on most cars. A lot of people that do this modification are also replacing worn out droopy springs so in that case, the ride height may increase or show no change at all. Also, after dropping the control arm, it will need to be aligned if you want the tires to last and want to realize any change in handling characteristics. The shims that were on the upper control arms is good enough to get you to an alignment shop. Do not go with factory alignment specs…they suck and the car will continue to handle like an overloaded milk truck. You want as much positive caster as they can get which is usually around +2 and at least -1 degree of camber. No more than 0.25 degree difference side to side. 1/8 toe-in seems to work well on these cars. There are a ton of other steering mods to be done if anybody is serious about cornering but the alignment specs above with the arning drop will get you a nice handling street car.

Would you ever do a video of you driving the car after any mods like this ? Just to get some insight of how it affects your car now that these parts are installed. Keep up the great videos!

Thanks for the video, getting ready to do this on my 65 Falcon.

Hi Andy, The Shelby Mod has nothing to do with changing the ride height.The fact that it lowers the car slightly is a coincidence. The purpose of it is to change the camber curve to make the outside wheel gain negative camber as the car rolls in a corner there by making the turn in better and removing the factory designed understeer. At the original height the upper control arm effectively pushes the top of the spindle into positive camber on turn in making the car roll onto the outside of the tyre and understeer. Lowering the rear pick up point with the Shelby mod allows the control arm to pull the top of the arm in and keep the tyre tread flatter on the road. I hope this is useful info, I'm not trying to be a smart arse. Jay

thanks Andy good video i love these how to video

Cars looking good with the drop!

Dang Andy i liked that spring compressor a lot better then the junky 1 i have.. Good job!

Great Video, the Shelby Drop isn’t really for lowering the car as much as the suspension. Autorestomod Jeff Ford has a great explanation of this on his channel. Thanks again for the video

Nice job, has a good stance.

Andy, your videos are great! I have a fully restored '66 mustang convertible. The wheels and suspension are stock spec. Considering all of the mods you have made to improve the handling of your mustangs, what made the biggest difference? Tire aspect ratio? Suspesion kit? Sway bar? Others. Thanks for the advice. Keep up the videos.

Hey Andy, sorry if I missed this in the video, but did you mention where you got those drill templates from?

I love when Andy says " We're going to have to jack the car up " ❤🔥❤🔥

I'm curious what the vertical difference was on your template, between the original holes and the small pilot holes. Are those 1" center to center or perhaps a bit less?

Great Video. 2 questions Did you leave the upper control arm connected to the ball joint? And what kind of spring compressor is that? Thanks!!

Can't wait to see the rear leaf to fix the back end. That will make a big difference on the look.

Nice looking car and I still think it's cool that the Shelby Drop is being used today. I just did it while installing a Street or Track coilover setup on my 65. By the way, what size wheel and tires are you running?

5/8 of an inch is what I got when I did mine too. Really helped with the handling though. I ended up cutting my coil springs to get the ride height where I wanted it. Look at Eaton GT spec springs for your leafs.

Thanks for showing us the process. What drill bits did you use?

May I ask where you got that spring compressor and how much it costs? Getting ready to do the same thing. Thank you.

Did you have to re-align the car after you installed this? I just put 1" lowering springs on my 68 but I would like for it to be a tad bit lower.

After doing the Shelby drop I've had a big hassle getting the alignment shop to align it to the correct new specs. The keep insisting that it needs to be done to original Ford factory specs. Which does not have enough positive caster. Very frustrating.

The Shelby drop isn't so much about lowering your car, it's about improving the angle of your A-Arm and improve your bump-steer. I did this on my 66 mustang and it is night and day difference in handling and driveability.

What spring compressor did you use? Been wanting to do this on my 66 coupe.

What did you use to maintain spring compression when you removed the spring?

I know I'm kinda late with this suggestion, but while the upper control arm was out, you should have installed the Boss 302 shock tower reinforcement plates.

Hi Andy, your car may have had the springs swapped side to side.I'm in Australia and '60s falcons had a slightly longer spring on the drivers side to allow for the weight of the driver. Don't know if you guys did as well but I'd imagine the idea came from the US falcon.

How does it handle? Any big difference in cornering?

What size are the tires?

where did you get your template?

So if the front end lowers, where does the weight shift. I know just wondering if you know. I also took it one more step with my modification from the 1980s. Drill the new Shelby drop holes. Bias the upper control arm shaft rearward 1/8th of a inch. I also slightly hexed slots for greasing. Here is the real trick. 1974 Maverick spindles have built in caster offset ball joint mounting. This allows for fewer shims. I have one shim per bolt. Then, I took a 1968 bog block Mustang coil spring and cut 1/3rd of one coil from the top. This allows the front to stay almost level, so no rolling fender edges. I easily used 235 x 60 x 15 tires. Inch front sway bar, all polyurethane bushings, Monte Carlo and Export brace. I also beefed up the upper control arm metal from underneath with 1/4 inch bar block for the two coil saddle bolts on each side. I used a 5/8th inch rear sway bar. The real leaf springs I added one half of an extra leaf. And if the alignment shop will let you, sit I the car, so the car is zeroed with your weight. The car handles unbeilivable, rides great on the highway. Also, most people never rebuild their steering box. Do that also. The shackles on the rear leafs are a bad idea when they can be reversed eyed and arched different.

The mod is about camber change not lowering

the Shelby mod drops the control arm geometry 1 inch, that is not the same as dropping the car an inch. and that was never the intended to drop the car an inch.

It’s not supposed to be a 1 inch drop. It was never intended to be damn lowering mod. The drop means dropping the location of the control arm. Shelby is cursing y’all all out. Smh

Veel beter

The purpose is not to lower your car by an inch. Not exactly sure who said or thought that. Not at all accurate and not the purpose of the mod.