Can any one explain what benefits there are with the hard motor mounts. I know it stiffens it up some but does this improve cornering, power transfer to the wheels or what. Also does it transfer a lot of vibration. I have pss9 and gt3 rear bar on my tt and like the better handling but I don't want to invite unneccessary vibration into the cabin. Dock, how do you like yours? Any input is appreciated.

 

depending on how hard the mounts are, you will get more vibration. the X73's arn't rock solid, but you will still get some vibration, but this comes down to how sensitive you are to the vibrations.

there was another thread on rennlist about these and most said the additional vibrations were negligable i believe.

There are two "stages" if you will for this upgrade, the X73 mounts, and the Rennsport mounts which are even firmer.

Gert at carnewal or any of your local speciality porsche shops (i.e. sharkwerks) can probably order them.

 

Silver,

I just had the X73 motor mounts installed last week. I also have the PSS-9 suspension. At first, I could barely discern any audible difference, but yesterday I took a 200 mile mountain ride with my son and the increased sound became more apparant. The increase in motor sound/vibration is very slight, but it is there. To describe it's nature....it is similar to the engine/chassis feedback you get with the F430, but nowhere near as strong/predominant. With the 430 you feel very connected to the car and the road, hear more noises, etc. - like you plugged your spinal cord into the seat. The X73 is a small step in this direction.

To sum it up, the X73 makes the turbo feel more connected to the road and provides the driver with crisper shifting, more precise hard cornering (feels like less body roll with the X73), a little more audible motor feedback and an overall feeling of tight, precision machinery vs. the softer feel of the stock car. I drove the car quite a bit today, as well, and I'm loving it. If you like the soft, quiet ride of the stock car, then it's probably best to stick with the stock mounts. If you desire to tweak the car more towards performance and sportiness, then it is one of many steps you can take in that direction. The X73 mounts bring a little of the older generation 911 feel to the 996.

 

I have a set for sale on ebay. I will sell them for $300 shipped. UPDATE: SOLD Thx Chris

 

ill take em, pm sent!

 

John D II pretty well summed it up the feeling and responsiveness of the engine with the x73 motor mounts.

However, from a physics point of view, I always understood that with any spinning object (such as the drive-shaft,etc) there are centers of rotation, moment arms, centripetal and centrifugal forces in effect. Remember looking under the hood of any old big block GM car (where it seems to be more obvious) and whenever you rev it up the engine would torque in one direction and rock back and forth. This is wasted energy...this same energy could be going instead through your drive train instead of rocking the engine back and forth. Hence the stiffer engine mounts will diminish this and improve throttle response, but at the expense of feeling more vibration from the engine.

At least that is my understanding of it....but I have been wrong before!