I actually just bought Unorthodox Racing pulleys, and they arent the same size. The crack pulley is smaller, and the alternator pulley is larger.

 

i unfortunatly have a d17a2 but what ever ill work with it just wondering how those pullys are treating you looking into them

 

^^BUMP^^
So....as I said above....Crank Pulley = smaller, Alternator Pulley = Larger. I would like to install them next week, as I have a 4 day weekend at the end of next week....Anyone that actually has them have any suggestions for me. PS....they are Unorthodox Lightweight Underdrive Pulleys. I have a 2004 Civic Si.

 

1. this thread is 2 years old
2. an aftermarket crank pulley is a bad idea. the honda crank pulley is called a harmonic balancer and is perfectly balanced. This is so that it won't damage your engine. The aftermarket crank pulleys are not perfectly balanced, and the vibration of an unbalanced crank pulley can cause serious engine damage. think of it like a tire. you know how an unbalanced tire vibrates while driving? well think of the aftermarket crank pulley as an unbalanced tire. The vibration of the unbalanced crank pulley will destroy your engine. Maybe not right away, but it'll catch up to you eventually.

 

I posted on this thread so that no one would yell at me for making a new thread when one already exists, and so that in the future anyone looking for information would only have to go to one place.

With that being said....I thought that my engine was internally balanced. I could be way off, as I doubt I have the experience you do, I just thought I heard somewhere that I wouldnt need to worry about that aspect.

 

the under drive pulleys that go on the alternator, a/c compressor, and power steering pump will be fine. i'm not sure about the crank pulleys anymore...

i just read the rest of this thread, and before i had been led to believe that the aftermarket crank pulleys were bad for your engine. i'm not sure anymore though since riceburner700 said he has one and it's been working fine, and he's a pretty knowledgeable guy, so i trust his judgement. just be careful and make sure you install the crank pulley correctly.

 

some of the Honda motors have a harmonic balancer on the crank pulley, some other Honda motors are internally balanced. i dont know what motors are internally balanced or have harmonic balancers on the crank pulleys. something u need to research before purchasing. if u replace a crank pulley that is harmonically balanced, there is a very good chance of completely destroying your motor internally.