Ok after showing pics of my engine, many people told me that it could lead to some crankshaft and/or main bearing problem.



Well im running this pulley for about 4 years now and never had problems but I begin to be really scared of it...

I never belived in those problems but after thinking about it I could maybe explain why it could lead to those problems. The vibrations is not the main problem... I think that what cause the problem is the fact that on one side of the crank there is about +-25 lbs of weight ( flywheel + clutch ) and now on the other side there is like 1-3 lbs or so. So just imagine when the engine is spinning and there is a huge differenc of weight on both side....

Well some people like me may dont have any problems in 4 years but if there is some minor difference in the engine assembly it may lead to some serious problem.

So should I keep it or throw it away... but she looks so damn good compare to my stock one ( Yeah I know im REALLY a rice boy when it come to the engine bay )

Mat

 

if you ran it 4 years no problem, why worry about what anyone else says. you know it works, right?

 

Ya Mat, 4 years later and your worrying about it now? I'm sure **** would have happened already. On a side note, I know a few guys in town that broke some oil pump gears from light weight UR pulleys and high revs/hp...

 

just a lil input, i will be starting my gsr build very soon and i plan to swap out my UR crank pulley for either stock or a fluidampr....... im not gonna take the chance.....

 

Ever heard of "harmonic balance"? A stock crank pulley has that characteristic. Light weight aftermarket pulleys cancel that balance for the sake of what?...... weight reduction? A little increase in RPM peak? The only aftermarket crank pulley that I would use is the one made by Fidanza.... damper design.

 

the reason why they are supposed to be bad is because if the lack of a harmonic dampener in them. ihave one on my car that i got for free from a friend and im only using it because my stock pulley was mangled. im gonna leave it and see how the motor looks when i eventually pull it apart

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thermal &raquo;</TD></TR><TR><TD CLASS="quote"> The only aftermarket crank pulley that I would use is the one made by Fidanza.... damper design.</TD></TR></TABLE>

any links to this pulley ?

 

Actually from what I've seen... the format of honda pullies is more of a vibrational dampener and not a harmonic... there just isn't enough rubber material in the honda pullies to really do much of anything.

I've personally been running a ctr n1 pulley for many thousands of miles and many abusive track miles with 0 issues.

I think that alot of the pulley issues that get claimed... started somewhere else. Urban legend style.

 

The saving grace for Honda's is the rubber timing belt.If it was a timing chain it would brake parts a lot faster.I've seen people destroy parts (cranks) in small block chevys in a couple races using a undampened balancer.But with supercharged engines (large rubber drive belt) I've seen engines last years with just a pulley drive hub with no damage.Personally I would still only run a dampened pulley on anything I built.
Glenn

 

There's a lot of testing proving that solid hubs are ****. Toyota did some testing, I think it's in an SAE paper somewhere... it basically explains why solid dampers will kill your engine, theres a good article about it in the last engine masters 'racing' issue... It's pretty well known info.

Also, i've seen some surprising testing between ATI, TCI, Fluidamper, and a solid aluminum moroso crank pulley (similar to unorthodox racing but for domestic V8)... the moroso was the lightest of the bunch by quite a bit but it still LOST power, the ATI and TCI weigh a good chunk more but still made a lot more power, relatively speaking. BTW This testing was not done by ATI or TCI, lol. Fluidampers okay but a lot of people claim that their product isn't very well suited to anything revving above 4000RPM lol.

Even if you paid me $1000 a year to use an unorthodox racing crank pulley on my race engine... I honestly wouldn't do it, I couldn't do it. That's just my opinion. Everyone has their own.

 

Read up on tests using aftermarket dampers. Some can be ok but others may not live up to claims. I posted some neg. feedback on one but didn't have the source info, it was deleted.

 

im definitely going with a stock pulley after readin this stuff......

 

From what I have experienced with, the damaging effects from running a solid pulley depends a lot on how much power the engine is pushing.

Most low power (200-250 WHP for example) and low redline setups never had issues with running a solid pulley... Once you get into high 300's + WHP, guys start to shatter oil pump gears and some have seen irregular wear patterns on the bearings. Sometimes it is a hit or miss, some said they had no problems even with big power.. However, one thing for sure is I've never seen cases alike happening with an engine using a harmonic damper such as the Fluidampr ot ATI.

My suggestion is to either put the stock pulley back on, or go with a Fluidampr or an ATI damper. I've switched to a Fluidampr (street version) and the engine became noticeably smoother especially at 5000+ RPM. It can only be a good thing when the engine runs a lot smoother... I would only imagine how damaging it could possibly be with a solid pulley which does the complete opposite (makes the engine a lot buzzier when a solid pulley is installed). With boost, power can be gained elsewhere safely

 

My freind broke his oil pump due to lighten crank pulley when he dynoed....He was pushing over 400 hp...they are not balance harmonically...go with either stock or fluid dampner...

i have seen lots of oil pump fail due to this...

BUT then again...if your not pushing the power...it doesnt effect it as much....ie 200 vs 500 (crank spins a hell of a lot faster at 500 hp compared to 200 hp) thats when balance becomes critical.....

 

from bigmoose's site

http://www.mtggraphics.com/big...r.pdf

http://www.mtggraphics.com/big...n.htm

http://www.mtggraphics.com/big...1.htm

http://www.mtggraphics.com/big...r.pdf

http://www.mtggraphics.com/big...k.htm

 

Great thread.

 

yeah its been covered before, but this thread is really good!

 

i talked to earl about this a few months ago. i have a built bottom end a6, and i had a d15 std. model "no rubber, super light" pulley on it. it didnt seem to cause any problems, but i got a bit freaked out by threads about b-series guys blowing up engines due to shattered oil pumps, etc.

i decided to just throw a stock rubber-filled si pulley on, and i feel no difference in power, and i have one less thing to worry about.

as far as earl knew, there were no mass-produced aftermarket dampners for d-series. if you find one, let me know. i'd like to see it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">
Most low power (200-250 WHP for example) and low redline setups never had issues with running a solid pulley... Once you get into high 300's + WHP, guys start to shatter oil pump gears and some have seen irregular wear patterns on the bearings. </TD></TR></TABLE>

Why would power have anything to say? Revs is what creates vibrations to the crank, right?

I mean a 200whp @ 9000rpm motor would create a lot more vibrations than a 500whp @ 4000rpm motor, right?

And by the way I run a stock ITR pulley with the ac and powersteering machined off. Can keep the stock rubber damper that way and still get it light .

 

thanks for all your reply. I will probably go back to my stock one if I find it. I really want to keep it safe even if I never had any problem before. Maybe there is already some minor damage to the bearings or maybe not but anyway I wont take the chance ! I will paint my rusty OEM pulley lol !

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Pompiuses &raquo;</TD></TR><TR><TD CLASS="quote">

Why would power have anything to say? Revs is what creates vibrations to the crank, right?

I mean a 200whp @ 9000rpm motor would create a lot more vibrations than a 500whp @ 4000rpm motor, right?

And by the way I run a stock ITR pulley with the ac and powersteering machined off. Can keep the stock rubber damper that way and still get it light .
</TD></TR></TABLE>


Both power and RPM, like I have stated on my earlier reply, contribute to these vibrations. A lot of the shattered oil pump gears that occur on our motors are boosted and pushing decent amount power... More power = higher intensity of each of those vibrations.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">Most low power (200-250 WHP for example) and low redline setups never had issues with running a solid pulley... </TD></TR></TABLE>

 

jdmland sells an oem crank pully by n1. so how can it hurt the engine may i ask?

 

people can believe what they want... but Ive witnessed first hand a shitty aftermarket pulley shatter my oil pump gears into 100 pieces on the dyno.
It wasnt a problem for me for years either.. It wasnt till I started to actually rev it out and make some power, that it shattered.

I was lucky it broke outward instead of inward.. I was able to take it off and put a new one on. Flush the oil and change the filter 2 times and was back on the road.
That single point of failure could have DESTROYED my turbo, my ENTIRE longblock etc.

Theres like 8 grand that will be wasted all because of a 50$ crank pulley.

Worth it? Hardly


I put a stock LS pulley on, reved the **** out of it and been runnin 450-500whp for a year and a half, no issues at all

 

let me get this right... a 200hp engine spinning to 9k doesnt spin as fast as a 500hp engine revving to 9k?!?!? how does that make any sense?

 

CTR crank pulley broke the oil pump on my old turbo Si the day I put it on. I will ALWAYS use the OEM pulley on anything of mine.