Lots of good advise but, lowering with suspension screwes up the ride[P
All depends on how you go about it.
If your suspension moves 6" before it bottoms out
And the spring has 250#/inch spring rate and is pressurized at lets say 800#
@ 6" compression that spring will be pushing 2300#
So you lower it 3" and you have 3" left of travel before you bottom out
your new spring needs to build 2300# in 3 inches of travel compared to the stock spring that had to build 2300# in 6 inches of travel to keep from bottoming out. It is going to have to be stiffer, no way around it.
if you do not make the springs stiffer it's going to ride nice on a nice new road and bounce off the ground and slam everywhere else.
coil springs have 2 engineerign features to pay attention to
The pressure and the rate
the pressure it uses to hold the car up and the rate it increases when compresses
The more turns of wire you have, the lower the rate
The bigger the wire, the more the rate.
a spring with a soft rate can hold the suspension at a certain height just by being a really
long spring compressed a lot
higher rate springs tend to be shorter before installation because it takes less compression for the weight of the car to mash them out at ride height.
If you just cut your springs or install shorter springs close to the stock rate yeah it's definitely going to ride terrible.
The difference between air springs and steel is the steel compresses at a more linear rate while the air in the air spring compresses at an exponential rate.
An air spring can start out soft and go firm as it compresses which is how they make a semi truck ride better without bottoming out.
Air springs have less internal friction than steel springs (more bouncy) so it takes more shock absorber with different valving to control them.
