the H&R bar is really almost as stiff as the GT3 bar. it's actually got the same number of usable adjustment settings as the GT3 bar. the H&R has three settings. the GT3 bar has five, but you really can only use three on the Box or 996 because the pick up points are different than the GT3. on our cars, the stiffest 2 settings of the GT3 bar cause the sway to actually bend rather than twist. it's hell on the power steering pump and gives some VERY funky steering feedback on the stiffest setting.

Addco also makes a set of bars. There are plenty of options out there, but you don't necessarily need to go with the stiffest you can find. Remember, stiffer bars actually REDUCE grip without changes to anything else and will somewhat effect everyday driveability, so you have to first decide what you're doing with the car before you pick the sway bar set and suspension you want.

http://www.addco.net/Plymouth-Susuki_AntiSwaybars.htm#Porsche

I know I've mentioned this before, but both the H&R and Eibach bars are SOLID! They are both WAY stiffer than the GT3 bar. And in my opinion, way too stiff for a Boxster.

The GT3 and M030 bars are just like stock - hollow - but stiffer.

the Eibach is actually a 24mm hollow bar. i called them before i decided on the GT3 bar to get a wall thickness; i calculated it to be roughly the same effective stiffness of the M030 'S' bar.

the H&R's are indeed solid. the rear is about 25% stiffer than the M030 'Base' bar on its softest setting. the H&R front is torsionally stiffer than the GT3 bar on its softest setting, but it has a longer lever arm. it is therefore just a TAD stiffer than the GT3 bar on full soft.

the GT3 front bar on the box is a bit stiff for the road, but GREAT for performance. the H&R rear is actually tolerable on the road at full soft. it's a bit aggressive at full stiff.

for giggles, i set the GT3 bar and H&R rear to full stiff for a day. WOW. WAY too stiff for town (and anything other than an oval track for that matter).

Well damn, then Eibach lied to me! They told me that it was a solid bar.

What did they tell you the wall thickness was?

if i remember right, it's 3.8mm, which is identical to the M030 S bar. when i upgraded to the GT3 bar, i already had an M030 S. i was looking for something a bit stiffer, so i compared the H&R, Eibach and GT3 bars. i remember the Eibach front being identical in stiffness to the M030 S, but being about twice as expensive.

AAdco sway bars???? anyone know anything about them?

Aadco sway bar

Addco, like I mentioned above. Just get the m030. Porsche knows what they're doing.

Both sizes?