there are 2 different durometers of poly you can use. the stiffer "race" version(Idle needs to be raised by 200rpm to eliminate HNV) or the softer "Street" version, with is supposed to be acceptable for a daily driver.

 

nonetheless, it will be far harder and harsher than the factory liquid filled mounts.

 

yes they are, but anything other than the stock oil-filled mount will do the same thing. Do you want comfort, or do you want performance...you can't have it both ways. But, if you want a mount that is "tougher" and "lasts longer" it's the only option that I know of. I just offered up what the Dude asked for...

from what I hear, the street mounts aren't bad at all, but I don't have them so I'll refrain from speaking on that point till I get mine in and get them installed. I'm fairly confident I have a turbo that is going out(I can hear and feel the turbo stop spinning under light acceleration...doesn't sound good...), so it looks like I will be dropping the engine soon for turbo upgrades and billet mounts.

 

Here the inside of the "valve body":