Why ROW M030 vs. US M030... IMO

[clord]

For what it's worth, this is my reply to a poster interested in my opinions of ROW M030 vs US M030 for the 996.

I converted to ROW M030 from US M030 for several reasons:

Slightly lower ride height...nominally -20mm front and -10mm rear.

Lowered ride height equals significantly better dynamic handling due to lower center of gravity. Race cars are lower for that reason.

I preferred the lower look of the car and the way the wheels filled out the wheel wells.

When I investigated, I found that the only parts common to the US and ROW M030 are the anti-roll bars. The shocks and springs (and alignment) are different. The Pano article on comparing the two pointed out to me that the US M030 (and all the other US suspension differences, for that matter including alignment) bias the dynamic handling of the car toward understeer and away from the way the factory balances the car for the Rest of the World. For whatever (legal?) reasons, they make cars for us that are balanced toward understeer. I wanted to start with my car balanced like the ROW. I tracked my C4 lightly before and after and can confirm that all that is true. Also, given the design of the front suspension you have a very narrow range of front camber adjustment available to you. At the raised US front ride height you are lucky to be able to get any negative front camber at all. At the lower, ROW front ride height, you can get up to about 1 degree of negative front.....the GT3 front alignment, for instance, specifies 1+/- degree negative. I ran about 50 minutes of negative for the street with the ROW and found the turn in crisp and to my liking. As for ground clearance.....personally, I found the ROW M030 no problem with the stock front bumper cover. Later, I install the factory GT3 AeroKit and then did find that I had to be more careful with driveways.