This post is not meant for the many experts we have in our midst but for those who are curious.
There is a method of calculating the centre of gravity for your vehicle. The single most important factor affecting roll over is your centre of gravity which is a imaginary point of concentration of masses distributed in the space of your vehicle.
In offroad conditions as your vehicle encounters either a forward or backward, left or right slope the vertical line passing through the centre of gravity shifts within the four corners of your tyre contact patch. In any condition if the line crosses outside the patch formed between your four tyres your car will roll over. Simply put the lower the CG the lower the chance of roll over. The higher you go easier to tip over.
SPOA "degrades" the centre of gravity dramatically as it totally realigns the distribution of masses in the car space and it is foolish to attempt this as you severely compromise your roll over angles. Unless ofcourse you are redoing the wheelbase and track amongst a few things to offset the compromise to CG on account of height increase
Some of the factors affecting your centre of gravity are your wheel base, your track, the weight of the axle up front and back. I am not an expert in this but Mr. Dhabhar can possibly share the equations that enable one to actually calculate the CG for your particular vehicle.
All of us can hop down to our local weigh bridges and do some measurements to figure this out and actually tabulate your roll over angles. Ofcourse you need some ramps to lift the wheels up from the contact patch to calculate how the CG shifts.
In summary do not raise your car unless you actually calculate and are fully aware of the compromise to your roll over angles.
A great part of offroading entails handling obstacles that entail sharp inclines. Please please remember that with each inch that you raise your Jeep you are compromising your roll over angles.
BTW the centre of gravity is very dynamic and even people sitting in your car can affect it. So changing engines, more people in the car than what you are used to, anything can throw you off guard as far as your CG and how your car behaves. The fact that your Jeep handled a particular slope well when you were alone won't mean it wouid behave the same when you have all your family or friends in it. Weight transfers can play riot with CG. So ! guys just be careful when your ride height changes. Why do you think Ferrari and Lamborghini have their cars so low? Its all about good old CG and ofcourse aerodynamics.
Last edited by DKG : 31st July 2009 at 22:47.
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