Help STILLEN LIGHT WEIGHT pulley
09-22-2012, 02:29 PM
#1
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STILLEN LIGHT WEIGHT pulley
I want to put this pully on but i have a question. Do i have to do any modifications? New Belts? or is it just install and go? Will the car act up?
09-23-2012, 02:29 PM
#7
http://i313.photobucket.com/albums/l...E/P1170880.jpg
1. Then google the problems with running an un-dampened crank pulley and what harmonics can do to an engines internals.
2. By replacing the pullies you tweak the engines harmonic balancer which in the long run will be trouble. I've heard it from enough guys to stay away from it.
"I have to agree that replacing the factory harmonic balancer with an aftermarket lighter pulley will pose an incredible risk of killing your engine.
We are talking about a total engine eradication just like what you saw on the photos that Sam posted. This looks so much like what happened to my friend 9 years ago on his BMW 328 with the E36 motor series ( Inline 6 in this case ).
As we all know, the popular method for making power pulleys on E36 engines is by removing the harmonic damper and replacing it with an underdrive lightweight alloy assembly. This is a VERY dangerous product because this stock damper is essential to the longevity of an engine. The substitution of this part often results in severe engine damage.
It is also important to understand that while the engine in a BMW is designed by a team of qualified engineers who understood the engine characteristics inside and out, these aftermarket power pulleys are created by the people who do not understand many of the very important principles of physics.
To put things simple, it is not the underdrive feature that kills the engine, but rather the lack of dampening the harmonic vibration that the crankshaft generates every time after each cylinder firing sequence. When this sinusoidal harmonic vibration coincide with the phase vector of the engine RPM, resonance frequency will occur. When this occurs, it must be counterbalance immediately and that is the exact job of the harmonic balancer pulley. If not, the power under the sine curve will keep on increasing or accumulate exponentially and that will guarantee to destroy the entire engine and the possible surroundings, such as the starter in this case of this VQ37VHR engine.......
Think 5 times BEFORE you put in an underdrive aftermarket pulley. The risk is 1000 times the reward.... Not worth it at all......"
Site of source: http://www.the370z.com/forced-induct...package-4.html
1. Then google the problems with running an un-dampened crank pulley and what harmonics can do to an engines internals.
2. By replacing the pullies you tweak the engines harmonic balancer which in the long run will be trouble. I've heard it from enough guys to stay away from it.
"I have to agree that replacing the factory harmonic balancer with an aftermarket lighter pulley will pose an incredible risk of killing your engine.
We are talking about a total engine eradication just like what you saw on the photos that Sam posted. This looks so much like what happened to my friend 9 years ago on his BMW 328 with the E36 motor series ( Inline 6 in this case ).
As we all know, the popular method for making power pulleys on E36 engines is by removing the harmonic damper and replacing it with an underdrive lightweight alloy assembly. This is a VERY dangerous product because this stock damper is essential to the longevity of an engine. The substitution of this part often results in severe engine damage.
It is also important to understand that while the engine in a BMW is designed by a team of qualified engineers who understood the engine characteristics inside and out, these aftermarket power pulleys are created by the people who do not understand many of the very important principles of physics.
To put things simple, it is not the underdrive feature that kills the engine, but rather the lack of dampening the harmonic vibration that the crankshaft generates every time after each cylinder firing sequence. When this sinusoidal harmonic vibration coincide with the phase vector of the engine RPM, resonance frequency will occur. When this occurs, it must be counterbalance immediately and that is the exact job of the harmonic balancer pulley. If not, the power under the sine curve will keep on increasing or accumulate exponentially and that will guarantee to destroy the entire engine and the possible surroundings, such as the starter in this case of this VQ37VHR engine.......
Think 5 times BEFORE you put in an underdrive aftermarket pulley. The risk is 1000 times the reward.... Not worth it at all......"
Site of source: http://www.the370z.com/forced-induct...package-4.html
Last edited by warpeacelove; 09-23-2012 at 02:45 PM.
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07-28-2014, 09:20 PM
#10
I'm bring this back up.....
Is there anything technical I can read on the 3.7L engine? I'm curious to see if in deed it has anything to do with the dampener. Is this engine internally or externally balanced?
Is there anything technical I can read on the 3.7L engine? I'm curious to see if in deed it has anything to do with the dampener. Is this engine internally or externally balanced?
07-29-2014, 12:57 AM
#11
In the same the370z thread referenced earlier, Conmam added an excellent post on the physics that are in play and the role harmonic dampers play to mitigate the resonant crank harmonics. It's well worth the read. I'm convinced to leave my stock pulley in place after that. I would think one could obtain the same or even more benefit by swapping in one of the 1 piece lightweight driveshafts, which would be a much safer option. It's noteworthy to add that driveshafts are subject to these same natural frequencies and harmonics as well.
GTM Performance Engineering: VQ37VHR Engine Build 700HP Power Package - Page 5 - Nissan 370Z Forum
GTM Performance Engineering: VQ37VHR Engine Build 700HP Power Package - Page 5 - Nissan 370Z Forum
07-29-2014, 01:13 AM
#12
Nissan 370Z Review; Engine (VQ37VHR) > 370z.com > 370z.com - Magazine
01-08-2016, 02:37 PM
#15
If this is the case, I think you would be fine. I would be surprised if Stillen would sell a part that would cause major engine issues. I actually just got a Stillen pulley installed myself when I needed a new auto belt tensioner.
I have installed lightweight (normal sized) crank pulleys on all of my cars and run some of them up over 100,000 miles with no issues.
I would advice against an under driven pulley as there are a lot of electronics on this car and your headlights will probably dim at every stop sign. I had an under driven pulley once and swore to never get one again for this reason.
I have installed lightweight (normal sized) crank pulleys on all of my cars and run some of them up over 100,000 miles with no issues.
I would advice against an under driven pulley as there are a lot of electronics on this car and your headlights will probably dim at every stop sign. I had an under driven pulley once and swore to never get one again for this reason.