please share all this documented info that you have

 

FWIW, there are a couple of user tests I've run across some years ago that claim a few hp improvement from a lightweight pulley in 300-350whp EVOs, but I'd be cautious drawing anything seemingly positive from that. Likewise, the intensity of the harmonics seems proportional to torque output, so a 500-600whp (or greater) setup is going to present a more serious situation.

 

These are what I've found with the under-drive pulleys, but again, this thread has nothing to do with power gains and more to do with removing rotating mass. I'm sure part of the gains noted below are from the ligher weight and some from the under-driven pulleys.

https://www.evolutionm.net/forums/803490-post22.html

https://www.evolutionm.net/forums/808165-post6.html

https://www.evolutionm.net/forums/ev...y-testing.html

https://www.evolutionm.net/forums/ev...s-pulleys.html Post #1 here is particularly interesting.

These posts are all from 5 years ago so part of my reason for making this thread was in hopes of newer information coming to light.

 

At the level of atoms, scientists are still trying to figure out what causes friction. There are two theories plus many scientists think, to some extent, both are true.

Theory A: the two surfaces moving past each other attract electrons in the opposite surfaces and these electrons, as they are dragged along, produce an electric current. This electric current encounters resistance. So, here, friction is the work done to overcome this resistance.

Theory B: the two surfaces moving past each other hit at high places and this causes the crystal lattices of the surfaces to vibrate. The vibrating surfaces give off sound waves. Friction is the work required to produce these sound waves.

Here is where it gets interesting. Long chain petroleum molecules (in other words, engine oil) tend to line up on the moving surfaces and dampen the movements of the crystal lattices so fewer sound waves are produced. Less sound waves equals less friction. The rubber damper in the crank pulley is supposed to be doing the same thing. So, I suggest, it also reduces friction.

 

for reasons that Ted B and AWDMotorsports have said, this is the reason why I haven't gotten one on my new evo. their advice should probably be taken....im pretty sure they know their **** . thats my $.02 and btw this is a very good thread i've been wondering about this myself to see if this was a "myth" or not

 

Very interesting and I can definitely see how that makes sense.

 

Ill take some beatings off the bearings over 5whp any day of the week.. In an all motor car you go for every HP but the Evo makes plenty of Hp that you can afford to keep the heavy damper..

Mike