When using modern radial tires on the rear wheel drive ’50/’60/’70’s Mopars, front wheel alignment can/should/needs to be adjusted for more and better steering response and overal safer handling of the car.
The following chart shows alignment specification values for various driving styles which can/should be provided to the alignment shop.
Sunday Cruising, -0.25°, +1.5°, 1/16″ to 1/8″
Daily Driver / Street, -0.5°, +2.5°, 1/16″ to 1/8″
High Performance / Street handling, -0.75° to -1°, +2.5 to +3.5°, 1/16″ to 1/8″
Autocross / Circuit track racing, -2.0° to -3.0°, +3.0 to +4.0°, 0″ to 1/16″ **
Dragracing, 0°, +1.5 to 2.0°, 0 to 1/16″ *
These alignment specs can be used for ’50s, ’60s and ’70s Mopars (Dodge, Plymouth, Chrysler, Desoto, Imperial) A, B, C, D, E and R-body cars.
All rear-wheel-drive cars. “Angled torsionbar” (F, J and M-body) cars need much more caster, upto 5.0°.
Moog’s upper control arm offset bushings (Moog K-7103, 2 sets needed) can help provide extra Caster for more better and stable steering.
However, the Moog bushings where originally intended for a different purpose, that is fix/help get wheel alignment into range again after an collision for instance, hence they were called ‘Problem Solvers’.
However, these ‘extra’ offset bushings can better used to get more Caster out of an alignment job.
So the bushings need to be installed so, that, after installation, the upper ball joints end up positioned further to the rear of the car.
* For dragracing minimum rolling resistance is the goal. Align the front end with the car in the halfway ‘nose high’ launch position, as it would go down the dragstrip.
** Some circuitracers and autocrossers prefer some toe-out, this is to help during cornering.
! Always set your car’s ride height before having it aligned !
Make sure to check all steering and suspension components. Worn bushings or balljoints will make an alignment job useless. Your alingment shop should check/point this out.
Also always make sure all tires are aired up to specs.
In 2005, Richard Ehrenberg wrote an article about wheel alignment-settings in “Mopar Action”-magazine where he posted the, now famous, “Skosh Chart” with recommended wheel alignment settings.
The complete article can be found on the Allpar-website