Quote:
Originally Posted by Dimman
I think of it in terms of leverage, which may be incorrect from a physics point of view, but whatever... The length of the 'lever' is from the roll center (intersection of points based on tire contact patch and angles of certain control arms. Or something... Can be above or below ground.) to the COG. So lower COG = less leverage to roll the car side to side, or pitch it front to back. Other way to resist roll/pitch is through wider track/longer wheelbase. Then we have anti-roll bars that are torsion bar springs that resist roll but not in pitch. Lastly (well, may be more, Old Greg is the guy to ask, I think) we have 'anti' suspension geometries that angle the motion of the control arms to act as a 'ramp' and naturally there are centers and the COG plays a role as well with them. COG can affect the % of anti-dive (forward pitch under braking) or anti-squat (rearward pitch under acceleration).
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Sorry I am late in the game, but as I posted in another thread,
http://www.ft86club.com/forums/showp...&postcount=263, lowering COG has some effect to the weight transfer. Not really much. Using the BRZ/FR-S as an example, roughly speaking, if raising the COG by 50 mm (about 2 inch), the increase in weight transfer under 1.00 G braking (to the front) is about 54 lb out of 388.2 lb, compared with 334.5 lb with the current 450 mm COG. This is considering the whole car, not per wheel.
I am not sure the typical spring rate is for any given car. 500lb/in? This is the number I got from Wiki. Can someone enlighten me on this?
The formula is described in many places. But the thing is, the weight transfer is proportional to the height of COG, and weight, but inverse proportional to the wheelbase. If you want to reduce weight transfer: lower weight, lower COG or increase wheelbase and you can achieve the goal. However, it all depends on where you did to see how much effect it can be.