Shelby drop
-
- Posts: 40
- Joined: Mon May 04, 2020 9:17 am
- Location: Oshkosh, WI
Shelby drop
As I understand it, it drops the inner upper arm 1” and can improve the handling in early Mustangs. I also understand that the 65 Comet shares the same arm and can be changed the same way, with the same template as a guide. Have any of you tried this? Thoughts?
Jack Bartelt
1965 Comet Caliente Convertible
1965 Comet Caliente Convertible
- Boss/Cyclone
- Site Admin
- Posts: 2739
- Joined: Thu Oct 19, 2006 9:55 pm
- Location: South Central Michigan (Near Michigan International Speedway)
Re: Shelby drop
I did it on my 65. I redid the front suspension at the same time so hard to say how much it helped.
1965 Mercury Cyclone former drag car, 1971 Boss 351 engine, 4 speed, ladder bars, etc. Now returned to a street car.
Larry
Larry
Re: Shelby drop
It increases available camber in the front suspension keeping more of the tire surface in contact with the road. The amount of drop varies with the equipment between 1" and 1 3/8" depending on the aftermarket equipment used. Be sure to use a provided template guide when drilling the new pilot holes. The location is critical that the drop be straight down, without a template guide provided it would be easy to do damage to your suspension. I will be doing it on my car when the new equipment comes.
The camber solution can be provided with offset upper a arms and adjustable strut rods as well without doing the drop. The drop won't change your stance enough to notice if that is your goal.
The camber solution can be provided with offset upper a arms and adjustable strut rods as well without doing the drop. The drop won't change your stance enough to notice if that is your goal.
Re: Shelby drop
The goal of the drop as I see it is to increase camber gain in bump.
Unless you are driving your car to traction limits in a corner you probably won't notice the change.
Anything you can do to increase positive castor will help your car run true down the highway but power steering will be necessary by about 4°pos for normal arms.
Fred
Unless you are driving your car to traction limits in a corner you probably won't notice the change.
Anything you can do to increase positive castor will help your car run true down the highway but power steering will be necessary by about 4°pos for normal arms.
Fred
Last edited by SASSY on Sun Feb 07, 2021 12:46 am, edited 2 times in total.
Re: Shelby drop
The template I used also moved the new holes back 1/8" to improve camber.
tom
tom
Re: Shelby drop
Yes it moves the upper ball joint toward the back of the car a little bit.
Re: Shelby drop
I also did the down 1 inch and back 1/8 inch. Can't tell if it helped anything, but then I did it with a full suspension rebuild. So it was so bad beforehand it's hard to compare.
1964 Comet Caliente, 302, upgraded to Toploader, front disk brakes ready for 2021 season after the snow melts!
- Jims65cyclone
- Posts: 2764
- Joined: Sun Nov 23, 2014 10:29 pm
- Location: Lexington, SC
Re: Shelby drop
You mean increase the positive caster, don't you Fred? Increasing the amount of positive caster will increase steering effort and straight line tracking, as well as improve high speed stability and cornering effectiveness. The Shelby Drop moves the upper control arm back 1/8", increasing positive caster, and drops it 1", gaining more negative camber which improves cornering by keeping the tire more vertical in the turns, keeping more rubber in contact with the pavement.
Jim
Re: Shelby drop
Thanks Jim I will correct my post!Jims65cyclone wrote: ↑Thu Feb 04, 2021 11:09 pmYou mean increase the positive caster, don't you Fred? Increasing the amount of positive caster will increase steering effort and straight line tracking, as well as improve high speed stability and cornering effectiveness. The Shelby Drop moves the upper control arm back 1/8", increasing positive caster, and drops it 1", gaining more negative camber which improves cornering by keeping the tire more vertical in the turns, keeping more rubber in contact with the pavement.
Jim
Fred
Re: Shelby drop
Re: Shelby drop
Agreed.
Fred
Fred
Re: Shelby drop
You gain +caster two ways. One can move the upper ball joint 3 degrees to the back of the car (IE Global West upper A-arms) or you can put in an adjustable strut rod and pull the lower arm forward. Or a combination of both. The stock shims accomplish this on a stock setup.
The same is true for Mopar. On my A-Body Barracuda it is accomplished with offset upper a arm bushings. The front bushing is installed to move the front of the arm away from the frame and the rear bushing is installed to move the rear of the arm toward the frame moving the upper ball joint toward the rear of the car. It made a world of difference on my 67 notch Mopar.
The same is true for Mopar. On my A-Body Barracuda it is accomplished with offset upper a arm bushings. The front bushing is installed to move the front of the arm away from the frame and the rear bushing is installed to move the rear of the arm toward the frame moving the upper ball joint toward the rear of the car. It made a world of difference on my 67 notch Mopar.
- Jims65cyclone
- Posts: 2764
- Joined: Sun Nov 23, 2014 10:29 pm
- Location: Lexington, SC
Re: Shelby drop
Fred, I can't remember, was it you who repositioned the upper ball joints in the control arm in order to increase positive caster? Seems I remember someone on here made that modification.
Jim
Jim
Re: Shelby drop
I modded the uppers for more negative camber.
I pulled the lower forward for more postive
castor but it removed the ability to achieve static negative camber adjustment on the upper shims.
Clear as mud?
Fred
I pulled the lower forward for more postive
castor but it removed the ability to achieve static negative camber adjustment on the upper shims.
Clear as mud?
Fred
Re: Shelby drop
Jim you & I talked about the ball joint move in pm's. I said I would do it if I ever tore back in to it. Lots of good tips like that on the opentracker site.
they talk about moving for camber & caster, & they had another one to move the BJoint dome for even more. also moving the spr perch out 1'' if I ever go back in. all the little things add up
link https://opentrackerracing.com/innovations/