Ran search no info,
Maby some builders can answer this best, what do ya think about these crankshaft fulid dampners? 180deg. from the old ultra light crank pulleys. Looks like a good theory, Gimick? anyone with insight?
kevin

Here's a link with info,
http://thmotorsports.com/fluidampr/f...s/g-52365.aspx

 

I'm just a noob but I was told that I should have one to prevent damage to the pulley or engine itself due to torsional vibrations on the crankshaft, furthermore my builder sited that a lightweight underdrive pulley would be even worse than the stock pulley. Mark @ SGP said that the Fluidamper weights about .5lbs more that the stock pulley.

http://us.st11.yimg.com/us.st.yimg.c...1978_114785988
http://sgpracing-store.stores.yahoo....n3pusetw3.html

 

fluidamper or the ATI damper are both great units.

there are torsional vibraqtions and harmonics that occur due to the forces applied duing each combustion process in each cylinder. These devices are designed to absorb the vibrations. these vibrations can cause major fluctuations in valve timing and can ultimately cause a crank failure.

 

Usually cause crank bearing failure before the crank goes.

 

I remember reading on this forum that about 3 people so far have blown motors which they attribute to the lightweight...unbalanced pulley that you get from UR. I don't know how true it is, but if the fluidamper is "balanced" and can minimize the chance of that happening, then its worth its weight.
I went from stock to UR to fluidamper. Motor is still in build process so I cannot give an opinion on performance aspect yet. Soon though...

 

what 3 people have had they engines "blow up" from ur pulleys? They are balanced, but not dampened. If ur f/i, fluidampr is the way to go.

 

I thought about going to UR pulley(s), but then decided to stick with my stock one(s) for reliability reasons.

 

I've seen the result of failure on the bearing and crank by harmonic vibration. Ugly stuff! Wasn't a UR pulley or a VQ35, but still enough to scare you away from an aftermarket pulley.

 

Try checking here for more complaints:
https://my350z.com/forum/showthread....pulley+failure

There are too many different threads beating up on aftermarket pulleys, whether its the CNR, KJR, UR, or whatever. Everybody has a specific complaint, whether its because they are built and rev higher, or just bad luck...I'm not judging but rather just sharing info. Please use the search function as this has been discussed countless times.

 

uh huh, that is a link to a thread about KJR pulleys--all aluminum with no crank seal--It is obvious by now that such pulleys lacking a pressed in steel collar will cause issues. That's nothing new. I knew this and stayed away from such pulleys as all should.

I was referring to your claim of "knowing" 3 people who blew up their engine running balanced UR pulleys (or any other pulley that uses a steel collar, i.e. not kjr)

I searched, and did not find what you claim. Please share your knowledge sir to back up your statement:

Please show me this on this forum^^^^^

 

Actually I said i remember reading about 3 people...allow me to clarify...I remember reading about this topic and I believe that 3 people on that thread were attributing their engine failures to these aftermarket pulleys. I can't find it now, but I'm sure if I thought it was that significant you or I could find it.
Check with Taurren, I think he chimed in with that info last time this subject came up.

 

+1 its a my350z urban legend. I had heavily searched for a proven failure due to a steel sleeved lightweight pulley. Yet, my search was futile. The only problems I ever saw was from improper install and/or a full aluminum pulley (like KJR, the example above).
If there is in fact a UR style, sleeved pulley failure that you know of please enlighten me. It just seems like one of those "i herd it here so it must be tru"

 

+1 Even DaveB, a known advocate against lw pulleys, admits there has not been a blown VQ engine/crank failure from a properly installed steel sleeved pulley like the UR:

 

sheees.... I should have been more specific, I'm interested in only the crankshaft fluid dampeners.
Any experienced builders maby have an opinion on this product?
It seems like in the whole deal, the amount of money some have wrapped up in these motors a few hundred is quite cheep insurance.
Kev

 

I beleive the VQs are internally balanced. The factory crank pulley has an elastometer band on it already. On my build I chose to stay with the OE crank pully. When I had the rotating assembly dynamically balanced the machinest did drill a few spots on pulley, along with the crank, to balance the assembly. I ran a UR pulley on my VQ30 for a long time and never had an issue.

 

I thought I'd throw this up here just for the sake of argument.
http://g35driver.com/forums/showthre...ing#post224754

I have a UR pulley installed on my car, but I don't deny the risks of harmonic vibration at the wrong frequencies causing catastrophic crank and bearing failure. I'm not advocating one way or the other in regards to the UR pulley and our engines. A Fluidampr or ATI pulley would eliminate the risk and is a very worthwhile investment, particularly for FI or engines that are raced.

 

Balancing the crank really has nothing to do with a Harmonic Damper (balancer).
The function is to absorb nasty frequencies or twisting of the crankshaft which
happens every time a combustion cycle occurs. It also helps the valve train
as the harmonics would be carried by the chain to the cams.
Also, bearing wear might get a benefit from it also...alot of pluses for
a balancer and no real negative effects. At the RPMs the VQ turns, it will
SURELY help!

 

Wow nice find!

Back to topic, I don't recall there ever being a Fluidampr or related product failure on these boards, and there are many people who swear by them if ya search around.

 

good luck proving a dampner or lack thereof destroyed the engine. just run one, who cares about the wimpy power gains from running an aluminum one. it isnt worth any potential risk. if a solid metal pully was adequate, why didnt our car come with one? surely it would be a lot easier to make a plain solid one than to put a dampner in it.

 

Hey Charles!, Thanks man, I have one on the way from SGP Racing.
Kev