yoshimitsuspeed
Automotive
- Jan 5, 2011
- 191
I guess while I'm here I'll throw up another idea that's been on my mind. Pendulum style harmonic dampers.
There are a lot of solid crank pulleys out there. Often used to reduce weight. There is also a lot of good info out there that suggests it's not a great idea to use them because they can cause added stress, harmonics and on some motors even very rapid failure. Now all the 4 cylinders I deal with are naturally balanced so we don't have to worry about harmonic balancers like some motors do, just the harmonic dampening that helps prevent harmful frequencies from increasing to a dangerous point.
I am developing a pulley that has an integrated trigger wheel and I would like to use a solid pulley as it will be much cheaper to make. I have also read mixed reviews on polymer dampers especially when building high performance motors because from what I can tell they are designed primarily for one frequency range and from what I understand the harmful frequencies can change as you change things on a motor like displacement, horsepower, RPM, Boost, etc.
If I could get a pendulum style damper to work it seems like it would be pretty perfect for what I'm trying to do. I would assume that any weights would help dampen these frequencies but in that article they make it sound like it takes a specific design to work with different motors. It has me wondering if this is a huge issue or something they emphasize to scare people away from adopting it. My main question is whether it would be possible for a design like this to actually amplify frequencies if it was the wrong diameter or weight? Or would it just work less well?
Some day I would love to actually make a few designs and test them monitoring crank speed with a fine tooth trigger wheel or something but that won't be happening any time soon.
Do you guys have any thoughts on this? Would some weights even if not ideal be better than a solid pulley? Or could it be possible for the wrong design to actually be worse than a solid pulley?
There are a lot of solid crank pulleys out there. Often used to reduce weight. There is also a lot of good info out there that suggests it's not a great idea to use them because they can cause added stress, harmonics and on some motors even very rapid failure. Now all the 4 cylinders I deal with are naturally balanced so we don't have to worry about harmonic balancers like some motors do, just the harmonic dampening that helps prevent harmful frequencies from increasing to a dangerous point.
I am developing a pulley that has an integrated trigger wheel and I would like to use a solid pulley as it will be much cheaper to make. I have also read mixed reviews on polymer dampers especially when building high performance motors because from what I can tell they are designed primarily for one frequency range and from what I understand the harmful frequencies can change as you change things on a motor like displacement, horsepower, RPM, Boost, etc.
If I could get a pendulum style damper to work it seems like it would be pretty perfect for what I'm trying to do. I would assume that any weights would help dampen these frequencies but in that article they make it sound like it takes a specific design to work with different motors. It has me wondering if this is a huge issue or something they emphasize to scare people away from adopting it. My main question is whether it would be possible for a design like this to actually amplify frequencies if it was the wrong diameter or weight? Or would it just work less well?
Some day I would love to actually make a few designs and test them monitoring crank speed with a fine tooth trigger wheel or something but that won't be happening any time soon.
Do you guys have any thoughts on this? Would some weights even if not ideal be better than a solid pulley? Or could it be possible for the wrong design to actually be worse than a solid pulley?