Hi guys I did a good search on this forum found some solid discussions saying how it WOULD be great but at the end nothing ever came of it. It seemed everybody agreed it was a great idea but it never came to fruition, any reason why not?

I wanted to upgrade my UDPs I already have a s/c with a 2.2 pulley so I figured somebody on this forum with my setup MUST have upgraded UDPs to yield better performance.

cheers

 

hey I just found an underdrive pulley from URD, has anybody tried this? and what the heck is acceleration horsepower does that mean at the crank?

and if that little mod will yield almost 10HP I think its well worth it.

 

The big debate on crank pulleys always ends up being balance and the bottom end of the motor. Some have found that a UD crank pulley significantly reduces the life of the motor. Take an H22A prelude motor for example. There is a guy that tore his motor apart after installing one and found significant wear on the main bearings...but that's a lude.

In all honesty, I have no idea about the 5VZFE and harmonic balancing. Sounds like it needs to be re-visited. Are you talking about a full accessory pulley set, or just the crank pulley, or what?

 

I would be just focusing on teh crank pulley because that is mainly all I can find, plus that has the biggest mass by far. If I remember correctly arent our 5VZFEs internally balanced? So it wouldnt impact bearing wear or any type of engine balance issue? Im also not the most educated thus my post

 

here she is FYI

http://www.urdusa.com/product_info.p...e5585968036d3f

 

Basically, the smaller your pulley, the more heat you will create which will in turn cause your engine to wear faster.

Now if you are willing to spend money of an Aquamist system, it becomes a totally different story.

Good Luck!

 

the 22rs and 22res have used underdrive pulleys for years on lce motors....

 

Who told you that pulley from URD was an underdrive pulley?? It is NOT. It IS a lightweight pulley but it is not smaller. It IS set up like the supergrip S/C pulleys in that it aids with belt slip.

Dave

 

Nobody really told me it was my assumption - sorry I may have used the wrong wording. From my understanding an aftermarket UDP was either one of the two or both --Lighter or smaller-- / --lighter AND smaller--. So I may have been wrong in terminology but once again back on track; Has anybody used it in their 3rd gens with their 3.4s and found it a worthwhile and dependable upgrade?

As Jim said it seems to have worked on the older 22s which is a good sign, thanks for the input!

 

there are much better, safer ways to gain horsepower...