Spindles etc
- Thread starter papadodge
- Start date
Dr.Jass
Pastor of Muppets
There are two theories on this:
1) It bolts together and works just fine.
2) There is potential for catastrophic upper ball-joint failure at full suspension compression since the taller spindle could theoretically over-angle the joint. The joint's stud hits side of the socket, can't move further, and snaps off.
The argument between the two camps is pretty passionate. I've never heard anywhere that it can improve the geometry, only that it won't hurt the geometry enough that you'd ever notice. The only improvement I know of with the factory setup is to use the Moog Problem Solver upper control arm bushings, and installing the rear one backward so you can get more caster out of it for better high-speed stability. Other than that, the factory geometry is pretty-well spot-on.
The correct way to do this is to use the upper control arms and spindles from a '73-'76 disc-brake A-car, or a '73-'74 E-body. These spindles are available new from SSBC, if I recall. Not cheap, but they are the right ones.
As an aside, there were no big-bolt A-bodies built prior to 1973 with the exception of the '68 Hurst cars. The big pattern came with the advent of the single-piston caliper, which did not appear in the parts book until the 1973 along with the first large-pattern rotors (drum brakes retained the small pattern until the end) and the revised spindles, brackets, etc. There was never a part number for a large-pattern 4-piston rotor, either. I dated a girl many years ago whose Dad had a Hemi Orange '72 Twister with discs, build date 6/72, and it was small pattern. That car wound up being parted out by myself and a friend quite some time later. He might even still have the data tag from that car.
The small-pattern cars use a smaller ring (register) on the hub to center the wheels, so redrilling K-H rotors (and small-bolt 8.75" axles) isn't a good idea--the only thing that would center the wheel would be the lug nuts... mystery vibration, anyone?
I've seen this swap done on a number of cars with no ill effects, but I wouldn't do it on my car nor would I recommend it to others. For what it's worth, Chrysler suspension engineers have spoken on it have unanimously been in the potential-failure camp when it comes to street use. Just because no one can recall seeing one fail doesn't mean it couldn't happen or hasn't. I don't want yours to be the first of which I've heard, either.
1) It bolts together and works just fine.
2) There is potential for catastrophic upper ball-joint failure at full suspension compression since the taller spindle could theoretically over-angle the joint. The joint's stud hits side of the socket, can't move further, and snaps off.
The argument between the two camps is pretty passionate. I've never heard anywhere that it can improve the geometry, only that it won't hurt the geometry enough that you'd ever notice. The only improvement I know of with the factory setup is to use the Moog Problem Solver upper control arm bushings, and installing the rear one backward so you can get more caster out of it for better high-speed stability. Other than that, the factory geometry is pretty-well spot-on.
The correct way to do this is to use the upper control arms and spindles from a '73-'76 disc-brake A-car, or a '73-'74 E-body. These spindles are available new from SSBC, if I recall. Not cheap, but they are the right ones.
As an aside, there were no big-bolt A-bodies built prior to 1973 with the exception of the '68 Hurst cars. The big pattern came with the advent of the single-piston caliper, which did not appear in the parts book until the 1973 along with the first large-pattern rotors (drum brakes retained the small pattern until the end) and the revised spindles, brackets, etc. There was never a part number for a large-pattern 4-piston rotor, either. I dated a girl many years ago whose Dad had a Hemi Orange '72 Twister with discs, build date 6/72, and it was small pattern. That car wound up being parted out by myself and a friend quite some time later. He might even still have the data tag from that car.
The small-pattern cars use a smaller ring (register) on the hub to center the wheels, so redrilling K-H rotors (and small-bolt 8.75" axles) isn't a good idea--the only thing that would center the wheel would be the lug nuts... mystery vibration, anyone?
I've seen this swap done on a number of cars with no ill effects, but I wouldn't do it on my car nor would I recommend it to others. For what it's worth, Chrysler suspension engineers have spoken on it have unanimously been in the potential-failure camp when it comes to street use. Just because no one can recall seeing one fail doesn't mean it couldn't happen or hasn't. I don't want yours to be the first of which I've heard, either.
well thanks for the great info, Well i will likely shoot for some used rims 1 cragar or 2 ralleys small bolt unless i run across a car locally that has the stuff to swich which is "Slim to none and slim is out of town" lol thanks guys papa-d ps dr.jass good advice on safety and that is priority 1
Diplomat_Wagon
Hiding In The Bushes While
I think I've got 3 or 4 sets of A-body disk spindles somewhere. Even a set of LCA's.