Monday, March 26, 2012

Upper control arms: [Shelby] Drop em if you got em

Today is as fine a day as any to discuss the 1" Shelby drop of the upper control arms I just completed.  It is an incredibly simple task, you just need a few items beyond your basic tools to get started.

First, order a metal template for the new holes to drill; I got mine from a guy who sells them on's a real nice template.  Alternatively you can get one from the guy at Daze suspension but I don't think it's as nice though it still gets the job done.  You'll also need a 17/32" drill bit.  It's an odd size but I've seen them at Sears, True Value, and of course, Ebay.  Just make sure you get one with a reduced shank to 3/8".  Mine was a 1/2" shank so I had to borrow a 1/2" chuck drill.  It stopped the project until I secured one and was annoying to say the least.  Do you know how many people DON'T have 1/2" drills?  Third, go to your favorite auto parts store and get a loaner spring compressor, but get the 'OEM style,' these have two hooks at the top and a large two-pronged fork that goes at the bottom of the spring.  Do not get a MacPherson strut spring compressor, or any kind of an an external spring compressor, or even the internal spring compressors with two hooks on the top and bottom; these bottom out on the spring perches.

The car is resting on jackstands and I've removed the shock tower cap and shock.  I have the spring compressor in place and am ready to begin wrenching on the nut at the bottom of the compressor to slowly compress the spring.

The spring is now removed.

This is a better picture of how the compressor tool is seated in the spring.  These are Grab a Trak 1" lowering 620's.  Handle this loaded spring like a BOMB.

I set it on the ground, stand off to the side, and keep my hands off to the side when decompressing so I'm out of the way if it were to pop loose.

Ball joint separator.  Toss the pickle fork unless you want to ruin your boot AND your ball joint.  The upper control arm needs to be removed and this contraption will be necessary to separate the upper balljoint from the spindle.  You can make nicer ones as I eventually will, or get a loaner tool from the auto parts store, but I was in a pinch and this demonstrates how you can scrap something together in a pinch to make your own homebrew balljoint separator tool.  I took a 3 or 4" bolt I had (don't remember the length), threaded a nut down on it, place a washer on top of that, and then a socket that will fit over the bolt threads.  The hex head of this bolt sits on the stud to the lower ball joint.  Thread the castelated nut on the upper  ball joint stud so the nut is flush with the bottom of the stud; the socket will rest against the bottom of this nut.  Now hold either the bolt head or the nut stationary with a wrench.  Whichever one is being held stationary, turn the other one such that the nut moves up the threads of the bolt.  This pushes up on the socket creating an elongating bar between the upper and lower ball joints.  Since the lower is bolted on and the upper isn't, the only one to break free is the upper.  Eventually it will pop loose and you've safely freed the spindle of the upper  ball joint.

Now take the bushing shaft, slide the template over the studs, and bolt it back to its original location in the shock tower.  You can see the small holes in the template right beneath the shaft which is where I'll start drilling for the drop.

Start with a small drill bit and slowly work your way up through sizes.  I think I stepped up through 5 sizes or so to get to a half inch hole, lubricating my drill bits frequently with motor oil.  Not only does this save your bits, it also makes it easier to keep the bit centered in the hole so you don't shift the hole over.  I was using high quality DeWalt drill bits, but still burned through my half inch bit before I even got the four new holes drilled in their entirety.  I had to go buy a second bit.  Finally finish the holes off with the 17/32" bit.  The bushing shaft studs will not fit through the hole if you try to leave it at 1/2", and even if you can get them through it won't be without damage to the threads.  You really need the 17/32" bit.  And be prepared for them to be a little spendy ($12 for the bit).  Now the second pair of holes are drilled exactly 1 inch below the originals.
While I had the upper control arms out I took the opportunity to tack weld the bushings to the housing.  I was originally planning on replacing both of the UCA's  because they were stripped out...a real bummer considering I had completely blasted them down and painted them (see Suspens(ion)ful entry a few years back), as well as replaced the ball joint with new Moogs, replaced the bushing in the spring perch, and replaced the UCA bushing shaft.

The control arms are bolted in place into their new location, 1" lower.  Torque the nuts on the shock tower to 90 ft-lbs.  Now I'll enjoy the significantly better handling, yet never know how much better it actually is since I have never driven this car.  Once I get the springs and shocks back in this will be complete.

No comments:

Post a Comment