Crank pulley
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Crank pulley
I recently got myself a lightened crank pulley but have heard a few people say it hasn't got a harmonic balancer in. Does anyone know what that is and how does it affect the motor i don't want to put this on and stuff up my motor.
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Re: Crank pulley
The standard pulley has layers of rubber that absorbs vibration. here is an explanation as to what it means (source: wikipedia):
"A harmonic balancer (also called crank pulley damper, crankshaft damper, torsional damper, or vibration damper) is a device connected to the crankshaft of an engine to reduce torsional vibration and serves as a pulley for drive belts.[1][2]
Every time the cylinders fire, torque is imparted to the crankshaft. The crankshaft deflects under this torque, which sets up vibrations when the torque is released. At certain engine speeds the torques imparted by the cylinders are in synch with the vibrations in the crankshaft, which results in a phenomenon called resonance. This resonance causes stress beyond what the crankshaft can withstand, resulting in crankshaft failure.
To prevent this vibration, a harmonic balancer is attached to the front part of the crankshaft. The damper is composed of two elements: a mass and an energy dissipating element. The mass resists the acceleration of the vibration and the energy dissipating (rubber/clutch/fluid) element absorbs the vibrations.
Additionally the energy transferred from the piston to the crankshaft can induce as much as 2 degrees of twist in the crankshaft, which has many follow-on effects on all engine elements that require adequate timing such as valve opening, cam timing, ignition timing etc.
Over time, the energy dissipating (rubber/clutch/fluid) element can deteriorate from age, heat, cold, or exposure to oil or chemicals. Unless rebuilt or replaced, this can cause the crankshaft to develop cracks, resulting in crankshaft failure.
Performance enthusiasts have been known to remove harmonic balancers, usually when the balancer is attached to the crank pulley, deciding that they aren't necessary and their mass reduces the performance of the engine. However, this is unproven and potentially very risky because the danger of damage to the engine from the vibrations the damper is intended to prevent is too high.[citation needed]
Certain cars, however, do not come equipped with an external balancer on the crank pulley, and as such, can have the pulley replaced with a performance oriented product which counter-acts these resonance frequencies."
In my opinion, I wouldn't change the pulley.
"A harmonic balancer (also called crank pulley damper, crankshaft damper, torsional damper, or vibration damper) is a device connected to the crankshaft of an engine to reduce torsional vibration and serves as a pulley for drive belts.[1][2]
Every time the cylinders fire, torque is imparted to the crankshaft. The crankshaft deflects under this torque, which sets up vibrations when the torque is released. At certain engine speeds the torques imparted by the cylinders are in synch with the vibrations in the crankshaft, which results in a phenomenon called resonance. This resonance causes stress beyond what the crankshaft can withstand, resulting in crankshaft failure.
To prevent this vibration, a harmonic balancer is attached to the front part of the crankshaft. The damper is composed of two elements: a mass and an energy dissipating element. The mass resists the acceleration of the vibration and the energy dissipating (rubber/clutch/fluid) element absorbs the vibrations.
Additionally the energy transferred from the piston to the crankshaft can induce as much as 2 degrees of twist in the crankshaft, which has many follow-on effects on all engine elements that require adequate timing such as valve opening, cam timing, ignition timing etc.
Over time, the energy dissipating (rubber/clutch/fluid) element can deteriorate from age, heat, cold, or exposure to oil or chemicals. Unless rebuilt or replaced, this can cause the crankshaft to develop cracks, resulting in crankshaft failure.
Performance enthusiasts have been known to remove harmonic balancers, usually when the balancer is attached to the crank pulley, deciding that they aren't necessary and their mass reduces the performance of the engine. However, this is unproven and potentially very risky because the danger of damage to the engine from the vibrations the damper is intended to prevent is too high.[citation needed]
Certain cars, however, do not come equipped with an external balancer on the crank pulley, and as such, can have the pulley replaced with a performance oriented product which counter-acts these resonance frequencies."
In my opinion, I wouldn't change the pulley.
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Re: Crank pulley
Kwl thanks dude
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Re: Crank pulley
I run a solid ALu Pulley on my VE till 8300RPM for 4 years now no issue.
Running on on the DET, NO issues so far
Running on on the DET, NO issues so far
2008 Mazda 6 MPS - Daily Drive
1\4 Mile:
1993 Nissan Sentra 200STI SR20VE – Mild VE
1\4 mile: 14.815 @153km\h @ ODI --- 1KM:195Km\h
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1\4 Mile:
1993 Nissan Sentra 200STI SR20VE – Mild VE
1\4 mile: 14.815 @153km\h @ ODI --- 1KM:195Km\h
Because Race Car
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Re: Crank pulley
jason i hade that whole motor balanced with all the sit i wouldnt swap it but u can, ca has no harmonic balancer
the toyota motors do and when you swap them with solid pulleys they like to blow up the oil pumps.
the toyota motors do and when you swap them with solid pulleys they like to blow up the oil pumps.
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Re: Crank pulley
Adrian with all due respect but the ca18det motor does have the Harmonic balancer i know cause when i decided to lighten mine on the lathe i realised it was a bad idee cause i also didnt think it has the ballancer, but it does.
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Re: Crank pulley
Hmmm never saw it on my old motor..
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Re: Crank pulley
could be because mine is a direct import and also one of the very last models not sure but i know the sentra, exa, langley and Sabre also have the balancer in, maybe on your old motor someone had already changed it?
Re: Crank pulley
All CA18s have harmonic damper in the crank pulley.
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