I've been looking through most of our sigs and i noticed none of the ones I have come across have a pulley. I mean I see it all the time in lancers but not in Evos' how come? I see Perrin has a pulley as well as Gruppe-s sells one for the evo.

The Gruppe-S Crank Pulley is CNC Precision cut from 6061 Aluminum. The pulley is NOT underdrive but weighs less than 1 lbs (14.8oz) compared to the 4.5lbs stock pulley. This reduction in rotational mass yields substantial improvements in both engine performance and response.

The Gruppe-S Crank Pulley will NOT cause problems with your engine. Despite rumors to the contrary, the early (1990's) 4G63's had machining issues with the Mitsubishi OEM crankshaft which was exacerbated by lightened flywheels and crank pulleys. The 4G63 EVO does NOT have this problem

I know how most of us try to enhance the performance of our Evos everyday, so I would like to know if anybody has one and what is their input on this, should it be done.. I know several friends who have done this one their STis, SRT-4, RSX-S I mean are we that special?

 

IIRC, 6lbs of rotational mass free'd equals 1hp... so 3.5lbs equals.... squat. Someone correct me if i'm wrong

 

I didn't know that thxs for sharing your opinion.. so my STi friend is BS me as he says it pulls a bit harder with his Perrin pulley.. hahaha classical suby dude BS.

 

yeah typical suby owner

 

This statement cannot be correct. I also agree that you wont feel squat, but you cannot say 6 less lbs will free up 1hp. A 20lb wheel that is 17" and a 20lb wheel that is 22" are different in that the 22" wheel will be harder to turn. The larger the radius the faster the outside diameter will spin.

 

So pretty much a pulley is worthless in a evo huh?

 

The answer is yes. It's pretty much worthless. I think there was a thread somewhere that discussed this a while back.

 

The engine needs a damper on the crank.

 

LOL that was funny

 

I did a lot of searching on this. It seemed the consensus was that it did make a difference off boost during low end driving. But, most didn't want to put one on their evo because of the lack of a dampner. This evo was the only car that people do not do this to. Most others cars this seems like a very common mod, but I can't say that for sure.

 

I'm not calling BS or anything but how do you figure.

I think there are more variable like radius (unless you were saying that for this specific pulley), mass (and where the mass is distributed on the pulley, towards the center of the pulley and whatnot), etc.
For example think of a pulley with a mass of 6lbs, it makes a difference if 5 of those lbs are concentrated furthest away from the center or if they are really close to the center. It will be harder to turn based on weight distribution.

Also I think it varies with engine speed, i.e. how much power does it take to turn the pulley X rpms.

 

I have Unorthodox's Racing pulley set (previous owner installed them) and Jarrod and even Dave Buschur himself told me to put the stock crank pulley back on. I've read numerious threads about problems with wearig out bearing faster due to not being a harmonic balancer like the stocker.

 

i've heard about bearing issues due to lack of dampening, you're better off getting the whole engine balanced and take out the balancing shafts

 

Hondas throw pullys on all the time and make a little power all the time. BUT they are ussually undrive pullys and alternator pullys. I am pretty sure honda engines dont need the dampener like evo motors do. I would never do a mod that might gain a few hp but possible wreak my car.

 

Exactly.. It never crossed my mind till my friends ask me.. how come you got no lightweight pulleys in your car.. and I was like huh..? So i looked at a bunch of ppls sig.. and started thinking about old dsm's was like oh yeah.. they tend to cause probelms..