Lowering the front end… what are the consequences?

[doctor4766]

When winding the adjustment bolts to lower the front of a Chrysler, what generally happens?
How do the wheels react?
Do they tend to come closer together at the point where they touch the ground like this \ / or is it the opposite effect, making the wheels lean in at the top like this / \ ?

[b5blue]

Increasing "rake" should have the tire top move inboard. Be careful as rake increases front geometry will force front suspension to move forward instead of up in jounce.   

[Gold Rush]

First step in service manual frontend alignment procedures is to make sure ride height is set correctly.  That said, I'd expect a frontend alignment will be needed at minimum.  I'd also expect much softer ride since you are relaxing the torsion bar twist.

[Kern Dog]

The camber goes negative as the ride height is lowered. Caster increases too. The toe setting changes a little too. If you're only changing it by an inch, personally I wouldn't worry about a REalignment. Beyond that, you might consider it. Lowering the car removes toe, raising the car increases it.

This chart was written after plotting the alignment numbers using a 1973-76 A body disc brake knuckle. The stock Charger/B body knuckle is close to the same numbers.
Note how the alignment does change as the suspension moves.

[Mike DC]

 
If you change the ride height by a visible amount, then you should also reset all the control arm bushings.  Loosen up the mounting bolts, jounce the front end a bit, and re-tighten them.  That way the rubber bushings are back to neutral (not twisted) at the new ride height. 

Failure to do this will wear out the bushings earlier.  The lower control arm bushings are already the front end's weak point (check the mounting areas for cracks in the K-frame metal itself). 



The camber change from lowering the front end is usually nothing to worry about.  Modern radial tires can take more camber than the suspension was designed to have at ride height. 

When you lower the front alone it tends to rake the chassis more (nose down, tail up) and that is bad for caster alignment.  These cars were designed for zero caster and you ideally want at least a couple degrees of it.  Increasing the rake (by lowering the front end) is pushing the caster slightly in the negative direction.  Not a lot.

 

Lowering the front end will quickly start using up your front suspension travel though.  People like to run shorter bumpstops to fix this.  But be careful if you run 14-15" wheels.

The factory designed the front end so you could bottom-out the front suspension and compress the tire sidewalls pretty far down at the same time, without hitting the undercarriage on the pavement.  If you shorten the LCA bumpstops then you're cutting into that margin of safety (unless the front end has 17+ inch wheels, which would work to offset it.)     

[Kern Dog]

Wow, Mike....I'm happy to admit that I could not think of anything that you missed there. I agree with all of it.
Good work, sir.