The Omey Pulley On Benzworld
09-06-2007, 08:52 PM
#29
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I am up in the Bay area on business and will put it on when I get home this weekend; having the time that is, lol. My 14 month old daughter is making me nuts, lol. I will post results of a positive or negative nature once I've driven the beast a few miles...Thanks for the info Jeff and talk to you guys in a few. 
Hey Jimmy,
I would love to see your beast when you are in the Bay. Send me a PM sometime when you are heading up here. Plenty of good roads around here to experiment with...
09-07-2007, 01:34 AM
#30
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'04 Silverado Z71 - sold all my Benzes and need another!
Sounds like a plan. Btw, I will be up there actually Wed-Fri of next week but without the Benzo. I'm staying in Hayward by my warehouse up there so if you're around, maybe I can check out your Benz, let me know.
I will probably not dyno my car now and probably wait until I get my headers. Once all of that is complete I will dyno and share results...
I will probably not dyno my car now and probably wait until I get my headers. Once all of that is complete I will dyno and share results...
09-11-2007, 02:12 PM
#31
Hi Jimmy,
You're right, from 1998-2000 the OEM harmonic balancer was rubbish, hence the recall. Mercedes since revised the design and I haven't heard of any problems with the newer balancer, but I could be wrong on this.
My concern about Omey's pulley stems from the fact that changing the mass of pulley will change the natural frequency of the crankshaft and change the frequencies that need to be damped. Omey hasn't exactly shown any equations regarding the damping characteristics of the harmonic balancer or the natural frequency of the crankshaft; he has shown us F=ma and I=mr². Now, this is not to say that it won't work. I'm just saying that it seems uncertain how much vibration engineering when into the design and that is what concerns me.
Anyway, enough of this. We're all old enough to make our own decisions.
I think we're really here to see what kind of results and impressions you get from the pulley. Keep us posted! Oh, and would you put it on already! 
You're right, from 1998-2000 the OEM harmonic balancer was rubbish, hence the recall. Mercedes since revised the design and I haven't heard of any problems with the newer balancer, but I could be wrong on this.
My concern about Omey's pulley stems from the fact that changing the mass of pulley will change the natural frequency of the crankshaft and change the frequencies that need to be damped. Omey hasn't exactly shown any equations regarding the damping characteristics of the harmonic balancer or the natural frequency of the crankshaft; he has shown us F=ma and I=mr². Now, this is not to say that it won't work. I'm just saying that it seems uncertain how much vibration engineering when into the design and that is what concerns me.
Anyway, enough of this. We're all old enough to make our own decisions.
I think we're really here to see what kind of results and impressions you get from the pulley. Keep us posted! Oh, and would you put it on already! Jeff, these are all legitimate concerns and believe me I have heard them all. The vibration engineering is superior to the stock design (which if you actually looked at it, its pretty damn crappy). All of those who have tested the pulleys so far have noted that not only is the engine smooth, its smoother than stock and feels even better than stock. The vibrations are far less with the AMS harmonic damper versus the stock one (its much thicker & uses a much better synthetic based rubber that does not weaken or erode or crack & peel over time). If you guys saw just how bad the stock pulley is when you take it apart and analyze it you would realized that the most dangerous thing to do is nothing at all.
Based on dyno evidense from hundreds of cars, pulley manufacturers have estimated that roughly every pound removed off the crank pulley equates to 2.7 wheel HP (roughly 3.375 crank HP). So as you can see mass plays a huge roll in the engines ability to accelerate. Different pulley models will make different gains on different MB models based on stock HP, stock crank pulley design, added modification, and other factors as well. The overall theory behind it is the same. Reducing the mass increases engine efficiency and allows more of the engines power to reach the rear wheels.
If you have any more questions check out...
www.abedinmotorsports.com/faq.htm
09-11-2007, 02:57 PM
#32
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'04 Silverado Z71 - sold all my Benzes and need another!
Update:
I installed my new pulley on Saturday and reset the ECU (thanks for the tips Omey). Let me tell you that right from the start the engine ran as new. No vibrations of any kind and the pulley is functioning flawlessly. I've driven the car for 2 days now and it already seems that it has an increase in power. I would still like to keep driving for the next couple of weeks and then will probably go and dyno it just for kicks. My mechanic compared the 2 pulleys (stock and new) and commented on how nice and smart the design is on the new pulley. He also drove the car and was very impressed. I will be in touch in the next couple of weeks with more info...
I installed my new pulley on Saturday and reset the ECU (thanks for the tips Omey). Let me tell you that right from the start the engine ran as new. No vibrations of any kind and the pulley is functioning flawlessly. I've driven the car for 2 days now and it already seems that it has an increase in power. I would still like to keep driving for the next couple of weeks and then will probably go and dyno it just for kicks. My mechanic compared the 2 pulleys (stock and new) and commented on how nice and smart the design is on the new pulley. He also drove the car and was very impressed. I will be in touch in the next couple of weeks with more info...
09-11-2007, 03:27 PM
#33
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Hey Jimmy,
So how long did the install take. And about how much? Does the computer have to relearn the new pully? What do you think, about 5hp?
So how long did the install take. And about how much? Does the computer have to relearn the new pully? What do you think, about 5hp?
09-11-2007, 04:28 PM
#34
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2001 E55K
Jeff, these are all legitimate concerns and believe me I have heard them all. The vibration engineering is superior to the stock design (which if you actually looked at it, its pretty damn crappy). All of those who have tested the pulleys so far have noted that not only is the engine smooth, its smoother than stock and feels even better than stock. The vibrations are far less with the AMS harmonic damper versus the stock one (its much thicker & uses a much better synthetic based rubber that does not weaken or erode or crack & peel over time). If you guys saw just how bad the stock pulley is when you take it apart and analyze it you would realized that the most dangerous thing to do is nothing at all.
Based on dyno evidense from hundreds of cars, pulley manufacturers have estimated that roughly every pound removed off the crank pulley equates to 2.7 wheel HP (roughly 3.375 crank HP). So as you can see mass plays a huge roll in the engines ability to accelerate. Different pulley models will make different gains on different MB models based on stock HP, stock crank pulley design, added modification, and other factors as well. The overall theory behind it is the same. Reducing the mass increases engine efficiency and allows more of the engines power to reach the rear wheels.
If you have any more questions check out...
www.abedinmotorsports.com/faq.htm
Based on dyno evidense from hundreds of cars, pulley manufacturers have estimated that roughly every pound removed off the crank pulley equates to 2.7 wheel HP (roughly 3.375 crank HP). So as you can see mass plays a huge roll in the engines ability to accelerate. Different pulley models will make different gains on different MB models based on stock HP, stock crank pulley design, added modification, and other factors as well. The overall theory behind it is the same. Reducing the mass increases engine efficiency and allows more of the engines power to reach the rear wheels.
If you have any more questions check out...
www.abedinmotorsports.com/faq.htm
I have no doubts that less rotating mass corresponds to less inertia which equates to less force required to turn and therefore more power; that's basic physics. My concern lies with the vibration engineering and now I'm curious about the durability.
Jimmy, glad it's working out for you. Very interested to see your dyno results.
09-11-2007, 04:29 PM
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'04 Silverado Z71 - sold all my Benzes and need another!
Yes, the ECU has to learn the new pulley which should take about a week according to Omey and I reset the ECU as well to spead up the process. As mentioned I already noticed more power and hoping in a week's time to feel a little more. I can't judge HP just by driving really but I can say that it feels a lot more than 5hp. Let's see what happens when I dyno it, hopefully in a couple of weeks.
