You are correct - More droop equals more downwards suspension arm travel.
I'm not a fan of the droop guage. It cant account for variences between tire/wheel manufacturers. Sometimes the axle height can change .5mm different between certain brands. That doesnt sound like much, but when determining droop, sometimes 1mm can make big difference.
First I install my set up and the tires on that I'm going to use and set my ride height. Then I measure the height of the axles while on a flat surface with a digital guage. (if all 4 of the tires/wheels are the same it will almost allways be the same on all 4 wheels).
If your ride hight is 5mm, install 5mm shims underneath your car (preferably all 4 corners) and remove the wheels. This is when I measure and adjust the downward travel. If the axle hieght with the wheel on was 24mm and the axle drops to 22mm after the wheel was removed, the droop is 2mm.
I prefer to start with 2mm downtravel on the front and 1mm on the back and then test drive and adjust from there.
It sounds like a headache, but its not that complicated or difficult or time consuming. Since I've started doing it that way, I havent used my droop guage since. There are other ways (probably better) to do it but unless you have a set up board that will get you close.
Remember, if you change your ride height or tires you shoud re-check your droop.
Last edited by Ed237; 01-21-2008 at 08:01 PM.