Harmonic Dampeners
 

I have been looking into purchasing an underdrive crank pulley for my car, but am not sure if our cars require a harmonic dampener or not?

I know the majority of aftermarket crank pulleys are not harmonically dampened, but do not know if that will be a problem on our cars. If anyone knows, or has any info, i'd appreciate it. Thanks!

Yes, i'd also like to an answer to this. (BP DOHC engine). It'd be easy for me to install it. Just need to know if i am gonna be killing the engine or not. (Some miata guys reported damaged engines and such)

hmmm,,, I knew there was a catch ,, well If I was installing it , i would just get the dampner anyway ...

I don't think u can get it seperate. AFAIK, it's built into the pulley. (it's the rubber layer between the 2 parts of the pully)