Lowering a W-body?

[Last American Indian]

First let me say that anyone should do as they wish, obviously, with their own car! That said, I believe it’s important for proper information in making decisions that affect not just the performance of such choices, but safety. Most will pass over this as just so much yada yada, but those that understand engineering, physics, the principles of energy & much more may take a moment to read & think about this.

Recently there was a mention in a post about the lowering of the W-body’s! It was stated that such a choice was a bad idea & I concurred, but I would leave it there at that time! I would like to address those reasons here! 

Reasons many people believe lowering a car's unsprung suspension is a good idea & will help a car handle better often comes from others who make assumptions & never do the math, really don’t understand the entire physics involved or know how to do the real work that is required to know what their actual numbers are & never truly put the car to a real test to prove it out! Yes they may take that car around a corner faster or it may corner flatter at the same speed as before & it feels good, but what if they really had to push it?

So the first fact, & you can research this yourself, is a double wishbone suspension & a macpherson strut suspension are worlds apart. The first can be infinitely fine tuned. The latter can’t! The first has many components that can be adjusted to affect roll center. The latter does not.

With a  double wishbone you can change caster, a lot, you can change camber a lot. You can effectively do a combination of movement of both caster & camber forward & out or in or rearward & out or in whichever you chose. With combinations to create many performance effects & these are just two parameters that affect suspension physics. With many double wishbone suspension you can find lowering spindles! This allows changes to the geometry of the lowered suspension with regards to CG while allowing RC to remain unchanged or altered whichever you chose. For the simplistic explanation, this amounts to the car being lowered, but roll center remains the same,with proper adjustments, as does suspension travel! 

In a Macpherson strut suspension this does not happen. There is no simple way to change caster! Camber you can, but it has limitations compared to a double wishbone. There are no lowering knuckles for Macpherson suspension for obvious reasons! The bearings are so large there is no room to alter the knuckles. As a result, suspension travel is negatively impacted. Roll center changes negatively, in a bad way automatically & you can’t do much to alter it.

Then there is this. How many truly know what their roll center is? How many know how to figure it? Better yet, how many of you can do your own wheel alignment? If all you did was put in lowering springs, & as such the car seems to corner better; then the answer to the above is you don’t know! This means if you were ever to be in a situation of needing to maneuver excessively quick, at a higher speed you might find yourself in serious trouble! 

In finality, suspensions are very complicated. There are over 100 mathematical calculations involved in setting up just a front suspension! Instant center, roll center, center of gravity, jacking force, anti jacking force, etc… to name just a few! In the end you can make an FWD handle! Not just well, but high end sports car well! But, not by lowering the car!