Whos running a Light weight crank pulley and light flywheel?
09-30-2005, 10:54 AM
#1
Registered User
Thread Starter
iTrader: (13)
Join Date: May 2004
Location: Sac
Posts: 2,141
Likes: 0
Received 0 Likes
on
0 Posts
Whos running a Light weight crank pulley and light flywheel?
Ive been told that our cranks cant hold up to this. That the stock crank pulley is weighted for a reason. So whos running them?
09-30-2005, 01:48 PM
#6
Registered User
Thread Starter
iTrader: (13)
Join Date: May 2004
Location: Sac
Posts: 2,141
Likes: 0
Received 0 Likes
on
0 Posts
Hmm this came from Ted at Scotts performance. He went into a long drawn out thing about it. There was a car their that they were replacing the crank on and said it was because of the pulley
Trending Topics
09-30-2005, 02:57 PM
#8
Registered User
iTrader: (1)
Join Date: Dec 2003
Location: Bay Area, CA
Posts: 162
Likes: 0
Received 0 Likes
on
0 Posts
This can become a great discussion, as I've been waiting for someone to come along this topic.....
To sum it up in one word- harmonics. Harmonics kills power, especially as the motor is pushed more and/or revved higher. Just an exaggeration, but think about it - if the dual mass flywheel is reducing some of the harmonics from the motor and tranny, and you take that away, what is engineered there to compensate?
Certain components are weighted or dual massed for the purpose of streetability and longevity. For a race car, lightening up the rotating mass works for quicker response, but the car is going to be torn down and rebuilt at certain times. What I've experienced is lightening this mass can definitely pick up more response in the lower gears, but becomes a moot point at higher gears. Other things include helping drop the revs faster, but one shouldn't be using the engine to brake anyhow. I could go on into other viewpoints, of how this works for N/A vs. Turbo cars, but save for a few others to chime in on this.
One also has to keep in mind that race cars are tuned and balanced/built to work in conjunction with other components, rather than slapped on and run. So of course, a "race" setup may not exactly work for a "street" setup.
I have a single mass 8lbs flywheel on my other car, but decided to keep the oem dual mass on my 350z. Why? Because I didn't want to deal with flywheel clatter, gear lash, and other untypical street sounds on a daily driver. Also, not to misquote Ted, but it was the lightweight flywheel that did it, not the pulley. I saw what happened to that motor, and that was definitely an extreme situation. Nonetheless, in my own experiences, I've seen the scenario with lightened/unbalanced components, and harmonics eventually wearing down other components. But to each their own.
To sum it up in one word- harmonics. Harmonics kills power, especially as the motor is pushed more and/or revved higher. Just an exaggeration, but think about it - if the dual mass flywheel is reducing some of the harmonics from the motor and tranny, and you take that away, what is engineered there to compensate?
Certain components are weighted or dual massed for the purpose of streetability and longevity. For a race car, lightening up the rotating mass works for quicker response, but the car is going to be torn down and rebuilt at certain times. What I've experienced is lightening this mass can definitely pick up more response in the lower gears, but becomes a moot point at higher gears. Other things include helping drop the revs faster, but one shouldn't be using the engine to brake anyhow. I could go on into other viewpoints, of how this works for N/A vs. Turbo cars, but save for a few others to chime in on this.
One also has to keep in mind that race cars are tuned and balanced/built to work in conjunction with other components, rather than slapped on and run. So of course, a "race" setup may not exactly work for a "street" setup.
I have a single mass 8lbs flywheel on my other car, but decided to keep the oem dual mass on my 350z. Why? Because I didn't want to deal with flywheel clatter, gear lash, and other untypical street sounds on a daily driver. Also, not to misquote Ted, but it was the lightweight flywheel that did it, not the pulley. I saw what happened to that motor, and that was definitely an extreme situation. Nonetheless, in my own experiences, I've seen the scenario with lightened/unbalanced components, and harmonics eventually wearing down other components. But to each their own.
09-30-2005, 03:29 PM
#9
I am running the Greddy TT at 600+whp a 9.9lb flywheel and the UR crank pulley. No problems yet...10,000+ miles later.
Honestly, this topic has been beaten to death. The stock crank is not balanced, like an aftermarket ATI. I think an aftermarket race ATI pulley might be a nice addition.
Honestly, this topic has been beaten to death. The stock crank is not balanced, like an aftermarket ATI. I think an aftermarket race ATI pulley might be a nice addition.
Thread
Thread Starter
Forum
Replies
Last Post
350z, balance, crank, crankshafr, crankshaft, flywheel, light, lightened, lightweight, longevity, mt, problem, pulley, pully, running
