From what I can remember somewhere reading around this board it's not worth it unless you replace the crank pulley and AEM doesn't supply that one, and in some cases if you do replace the crank pulley things seemed to have gone wrong...I guess it depends on how they are installed. Someone correct me if I'm wrong.
Crank pullies have harmonic balancers inside them. Harmonic balancers reduce crankshaft vibrations in the higher RPMs. Lightweight crank pullies remove the harmonic balancer from the pulley. This increases your chances of spinning a rod bearing, or a spinning a crank bearing because the crank may get out of balance in the higher RPMs. It's not a good idea on a high revving Honda cause they rev so damn high.
I do believe in crank pullies making power, but it depends on the application. We friend got a lightweight crank pully for his Celica (I forgot what brand it was but it's not AEM) and he gained around 5 WHP (I forgot the exact before and after dyno figures, this was awhile ago) just from the pulley. It was only $99 so it wasn't a bad mod for him. But he is taking the chance of the harmonic balancer deal. No problems yet for him though, the only thing he doesn't like is his a/c doesn't get as cold and his lights dim when he comes to a stop...cause all that stuff is turning slower.
haha i am. Im ordering hondata today and then when i make the cash or my clutch goes, im going to get the flywheel.
Im thinking about buying a set of these pullies though, my friend has a set on his prelude and he said they were one of his best mods. No one on here has intstall them, i think, so i mean it cant hurt to try it out.
Maybe I can shed some light on the subject. I have been talking with Unorthodox Racing concerning their Underdrive Pulley Kit currently in development for the base RSX. BTW, the Kit should be availabe first quarter '04. Anyways I was concerned with the harmonic dampeners myself so I emailed the head mechanic with UR and this is what he said:
We are still looking at releasing the pulleys early next year ('04). People are getting the pulleys confused with the harmonic dampers found on 90 degree V8 and V6 engines. The pulleys on most of the new import and smaller domestic engines have an elastomer (rubber ring) incorporated into the pulley that looks similar to a harmonic damper. The rubber in the OEM pulley serves as an isolator, which is there for noise suppression from the cycling of the A/C compressor and P/S pump and the groan of the Alternator when under load, What the manufacturers call NVH (Noise Vibration & Harshness) when referring to passenger compartment noticeable noise and vibration. If you look at some of the pulleys on older imports there is no rubber to be found. We have samples of mostly Honda, An Altima, 1.8L Eclipse, 2.3L Ford, Chrysler 2.2L, 1.8L VW and a few others all with no rubber. The purpose of a traditional harmonic damper is to keep the crankshaft from cracking which is not necessary on your engine. You have probably heard stories about bearing and oil pump failures. Any abnormal bearing wear is due to a lubricating issue, The most common examples are using the wrong weight of oil, a faulty head gasket or poor engine assembly practices. The idea of increased bearing wear from not having a damper on the engine is false. Using too heavy of an oil can shatter the oil pump gears. Most of the time oil pump failure is caused by something being sucked up into the pump. There are companies in Japan that have been producing upgraded pump gears for more than 10 years now. The fact of the matter is the pulleys have been out there running for over 5 years and there have been no failures attributed to the pulleys. There is a lot of internet hearsay about the pulleys, too often people are too quick to blame the pulley first rather than looking into why there was a problem and then go and post it on a message board. You really have nothing to worry about. If you would like to read more info on the subject, visit the FAQ section on our web site or you can contact me directly at (631)-586-9525 Ext. 12.