OEM /6 mount, Mad Dog Options

[930cabman]

Making the conversion to a 6 cyl, we have several choices to make with mounts, exhaust, fuel, oil tank, engine tin, ....

I recently purchased the OEM mount from Mad Dog, you couldn't ask for a better fit. It nestled into the recess and allowed basically no room for error. I socked it in with a couple self tapping screws and went ahead with the plug and fillet welds.
I removed the paint from the mounting surfaces with paint stripper and cleaned it up with a sanding disc prior to welding

From what I understand the factory placed additional reinforcement in this area. Running the welds for this mount I sensed it the way my MIG was acting. I bet you could pick the entire car up from this mount. Very well done Mad Dog

[930cabman]

I have welded the Mad Dog chassis portion into my conversion project, but the 2.7 is still at the engine builder. Mad Dog states a Wevo mount is required to complete the installation, about $90.

[Superhawk996]

I have welded the Mad Dog chassis portion into my conversion project, but the 2.7 is still at the engine builder. Mad Dog states a Wevo mount is required to complete the installation, about $90.

@930cabman

Per previous notes from @mb911

The Wevo mount goes into the 2nd plate with round hole that was supplied with the Maddog mount. Ben seemed happy with the isolation from the Wevo mount.

OEM 914/6 mount eliminates the adapter plate and the wevo mount.

As an automotive engineer that has worked on NVH and highly values low NVH in my own vehicles, I will be using the 914/6 OEM mount for the following reasons

1) Now readily available and only slightly more expensive than the Wevo mount.

2) I don't like the way the Wevo mounts in the secondary adapter made of flat plate. That flat piece of plate steel isn't very stiff in dynamic bending in Z plane relative to the rest of the mount that has lots of form and is directly welded to the chassis. What your really want is a mount structure with at least 10 times more stiffness than the isolator itself. I'm not convinced the steel plate and the Wevo isolator will achieve this goal.

3) The OEM mount has way more rubber for isolation and will have a much lower rate in Z plane than the Wevo mount and will better faciliate meeting the ratio of 10:1 between mount stiffness and isolator stiffness. The result should be much better isolation.

4) Based on the above info, I belive Porsche did their homework and designed the OEM 914/6 mount towards this end. Good isolation in the Z plane without overly compromising X/Y plane that would lead to diminished steering and handling performance.

People have vastly different appreciation for NVH so by no means and I saying the Wevo mount won't mount the engine. I'm sure it will. I also belive it probably does a decent job based on Ben's feedback. However, for reasons above, and my desire for a powertrain mount that is optimized, I belive that is best achieved with the OEM engine mount, and that is what I'll do.