Difference between Aftermarket Crank pullies.
 

whats so special about crank pullies made by aftermarket companies like aem n crap compared to stock????

i never seen an aftermarket one so i am assuming it looks the same and the only thing i can see being different would be its probably painted for looks and is lighter for some odd reason.

you got it. I'm pretty sure all they are is just a lighter pulley

yeah they're just lighter but i read something from somewhere saying a lot of them aren't designed to handle the vibration like a stock one and can lead to an oil pump failure or something. i could be wrong but it makes sense.