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Discussion Starter · #1 ·
I saw a post by 2k1dragsentra regarding upcoming mods, which included flywheels. I have VERY basic understanding of how engines work, and I have never come into contact with information on what this component does and how the aftermarket would improve its functionality. Any info. would be appreciated.

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2001 Blackout SE w/ PP, sunroof, debadged, Stromung exhaust, more to come...
 

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Wow !!! Another big technical question today. The flywheel does exactly what its name says it does, it is a wheel that flies around. The flywheel is attched directly to the crankshaft on the backside of the motor (the side that connects to the transmission). It looks light a big flat gear with teeth. The main thing it is used for is starting the car. It is what the starter hooks up to and spins when you turn your key. Attached to the to the flywheel is either the clutch disk or the torque converter, depending on what transmission you have. The reason you might want to change the flywheel is that it is a very heavy peice of rotating mass. Putting a lighter one on will not increase Hp but it will free up some accelearation. But hold up right there, if making the flywheel lighter makes the car faster why doesn't Nissan put a light one on in the first place? For good reasons, Drivability. The heavy flywheel provides rotational inertia (spinning momentum). Cars with light flywheels are much easier to stall. The motor is more apt to choke on a clutch release because it doesn't have as much inertia. Light is good but not too light or your car will die every time you let the clutch out. Most cars with light flywheels need to be launched at a higher RPM and they are harder to drive smoothly. If your willing to give up some smoothness for accleration, go for it.

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rschauby

2001 Sentra SE w/PP auto (radium)
1998 SE-R 5spd
 
G

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Actually, Auto's don't have a traditional flywheel. They have a flex plate I believe. It's a bit different.

Also, the flywheel helps smooth out the power pulses the engine creates. For instance, if your driving at low speeds in 1st gear, the car will drive more irratically with the lighter flywheel. In addition, as rschauby stated, off the line performance is hindered somewhat.

The plus side is that the engine is able to rev up much, much quicker because it is moving several pounds less of rotating mass. A underdrive pulley is like just over 1.5 pounds lighter on our car. Now, a flywheel can be 8~12 pounds lighter. It makes a much bigger difference. As with anything though, there are pro's and con's.

The biggest con would have to be the difficulty of the install. YOu have to remove the transmission to access the flywheel. It is a BIG job.

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2001 SE, P/P, 5 spd Cloud White.
MODS:
- Stromung Stainless Cat-back.
- Hotshot CAI

"I always wanted to be somebody, but I should have been more specific."

[This message has been edited by maxximtl (edited March 22, 2001).]
 

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Discussion Starter · #4 ·
Ok! Thanks for the quick (and indepth) replies! This doesn't seem to be a mod I will be doing but its nice to expand my knowledge of the engine that little bit more.

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2001 Blackout SE w/ PP, sunroof, debadged, Stromung exhaust, more to come...
 
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