I have a unorthodox racing underdrive pulley on my motor, ive had this for almost 4 years, anyhow, along the way everyone says oh those are bad, blah blah, blah blah... Ive never been given an exact reason as to why there bad, but ive been told, theres no rubber dampner, and the dampner is there to dampen the vibrations etc.. from the motor,

Sounds logical, so i stop by http://www.apimportsource.com and pick up a crank pulley off a b18c block because this weekend im going to replace the water pump and timing belt, and i figured since the "underdrive pulley" is the devil, i will put the stock one on, guess what.... stock pulley does not have this miracle dampner either.


All ive ever heard was rumors, but ive never heard any real world experience about these pulleys, so convince me as to why i should put the stock pulley back on. (i went ahead and bought it)

This might be something that belongs in the na forum, i just figured i would post it here, since im turbo. If it matters im running about 5 lbs, and will probably bump it to 10 by the end of the year.

Ive had mine for almost 4 years, and i know of 1 other person that has had one for about 2 years, and he has not had problems either.

 

an underdrive pulley slows down the rate at which your accessories spin for like a 2 hp gain. Complete waste of money

 

im pretty sure they will make more than that, especially with boost.

 

it also makes your car volts drop and not charge the same

im runing one, i don't like the lowend with one, but the highend is alright with it

 

ive got a voltmeter, and your right, it does make it drop a little lower, but like i said, 4 years no problems thus far.

i need some evidence that this is going to be a problem otherwise i will probably keep it, im open minded about taking it off.

 

It's not that. It's that it doesn't absorb the vibrations coming off of the crank from the engine rotating (Pistons, rods, the entire rotating assembly vibrates, and a ton of vibration will in turn shatter the oil pump and put alot of stress on the main bearings)

The stock one DOES have it built into the pulley.

Stock is fine for OEM rods/pistons, but with beefier/heavier aftermarket pistons and rods, you will need something to absorb those frequencies, such as a fluidamper, which will absorb a variety of harmonic vibrations, not just the ones sent from the stock rotating assembly.

 

what ive heard is that the kits dont come with a harmonic balancer and if you kill it....BOOM, thats what i heard from this guy but his car was all body kit and subs if ya know what i mean...

 

Id rather run .01 more psi than invest all that money and work for the same gain.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tapen00n &raquo;</TD></TR><TR><TD CLASS="quote">what ive heard is that the kits dont come with a harmonic balancer and if you kill it....BOOM, thats what i heard from this guy but his car was all body kit and subs if ya know what i mean...</TD></TR></TABLE>

the stock pully does not have a harmonic balencer, thats what im getting at, also the ctr n1 pulley, also doesnt have a harmonic balancer....

im more than likely putting the stock pulley back on, i just thought somebody could specifically point out a flaw in the ur pulley, and so far i havent heard anything that really states this is bad.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Muckman &raquo;</TD></TR><TR><TD CLASS="quote">Id rather run .01 more psi than invest all that money and work for the same gain.</TD></TR></TABLE>

its not any more money or work, i have to change the timing belt and water pump anyways, and i already have the parts...

 

All the gsr's I've seen are dampened.All the b series I can remember are dampened.The d-series vx had a solid one but that was made to turn about 3k rpm.The C1 is undampened and plenty of oil pumps have seen there last days because of them.The rubber timing belt does help a little.If these were chain drive they wouldn't stand a chance undampened.The domestics with roots blowers get away without them because of the big drive belt.
Glenn

 

i will say it and MISTA BONE here as well will back me up

i have been thru this before

lighten crank pulleys will trow the balance of the engine off..
they will not damper the vibrations of the engine efficiently

wich cause : acelerated Main bearings wear

best pulley is the one that came with the engine

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by slowpokesi &raquo;</TD></TR><TR><TD CLASS="quote">the stock pully does not have a harmonic balencer, .</TD></TR></TABLE>

take a close look to the stock pulleys
they are 2 piece parts joined by a rubber insert... take a very close look and u will see

 

Honda motors are internally balanced, so they really don't need a dampener as much as let's say a Mitsu motor. I personally like to have the benefit of the doubt, so I still have my stock pulleys. I think that it gives me a peace of mind and I don't need the extra few ponies..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by USDM 4G VTEC &raquo;</TD></TR><TR><TD CLASS="quote">i will say it and MISTA BONE here as well will back me up

i have been thru this before

lighten crank pulleys will trow the balance of the engine off..
they will not damper the vibrations of the engine efficiently

wich cause : acelerated Main bearings wear

best pulley is the one that came with the engine</TD></TR></TABLE>

ive had my unorthodox crank pulleys and accessory pulleys on my b18b for quite some time now... well over 15,000 miles now. No signs of anything bad...however the only thing is, my volts drop to around 12 sometimes out of nowhere. so thats the only negative thing i have noticed... plus i never spin my motor up to 7000+, i think maybe a harmonic balancer would be more beneficial to those motors which are taken up well past 7k rpm.

 

my friend had a set pulleys for his mkIII supra..they tend to eat his belts away..

 

here's a pic of a d series pulley, courtesy of fluidampr:

 

The experience I have had with the unorthodox pulley is that four of us ran them from our shop all turbo b-series and out of the 4 the only one that held up was a b20 turbo (i think because he wasnt reving as high as the vtec ones) but the other two shattered the oil pump in a million pieces mine luckily held up after the fact of my friends breaking so i changed mine back to stock (which has a dampener in it)... now i found that the earlier ls integra didnt have the dampener but b16a b18c1&5 & b20 all had dampeners......


I feel as long as you arent reving it past factory rpm then the factory dampened one will be fine because that pulley is designed to rev to that particular rpm, anyone feel differently if so give info please this topic could get interesting..