E36S50

Guys,

I've searched the archives and it appears as if the MKII GT3s have 228# front and 542# rear springs. This is softer than I would have gussed, knowing how firmly it rides for a ~3100lb car.

The front, being a Mac strut, probably has a motion ratio of ~1:1, but does anyone know the motion ratio for the rear 996 suspension?

It seems as if Porsche might have gone with big sway bars on these cars in place of heavier springs. This is not a combo I favor and I am thinking about going to stiffer springs and smaller sway bars.

Also, are the GT3s suspension bushings "special"? I think they are all still rubber, but maybe of a harder material compared to a normal C2?

Thanks

Karl S

MkII springs were stated to be about 20% stiffer than the MkI, although the rear spring is a progressive, so it may feel a little softer until it loads up.

Karl

bob_dallas

Rears look to be direct as well - I'd guess the ratio is close to 1:1 if not exactly.

clord

A couple quotes from the PAG GT3 Product Information book:

"....the standard rubber bushes used on the 911 Carrera have been replaced with much less pliable metal alternatives."
"....On the new 911 GT3, however, Porsche engineers have used stiffer spings and dampers than on the 911 Carrera (sic) to achieve a much more active and immediate ride. If rubber bushes had been used on the various mounting points, there would have had to absorb a much greater proportion of the forces passing through the suspension components..... In the case of the 911 GT3, the solution to this problem is to use metal bushes at a number of key locations, including on the inboard mouting points for the rear longitudinal links......maintain a more consistent toe angle and camber setting, while ensuring a much more clearly defined response from the spring and damper units......metal bushes for the spring seats on the rear struts, the rose (solid ball) jointed top mounts on the front struts, the front tie rod joints and the front anti-roll bar linkage.....necessitated by the change in front axle kinematics resulting from the reduction in ride height by approx 1.18 in." "...it was possible to raise the corresponding mounting points (rear susp) by a further 0.24 in to improve the overall kinematics on the axle."

My conclusions: Yes, some bushes are different. Some suspension geometry is different and optimized to the GT3. PAG engineers did a lot of careful work designing and testing the GT3 suspension.