Underdrive pulleys = Increased MPG
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Joined: Nov 2001
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From: Los Angeles area
2001 C240
Underdrive pulleys = Increased MPG
After about 5,000 miles on my underdrive pulleys, I calculate that my average gas mileage has increased about 2 MPG. Even at $2.20+ per gallon, it would take years to pay for the pulleys, but that's not why you get them. Anyway, it is a nice bonus....
MBWorld Fanatic!
Joined: Jan 2002
Posts: 1,869
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From: Los Angeles
GL450, Sienna SE
Originally posted by Dave OH
Only problem with adding more power is... more temptation to push the pedal more often... that equates to worse gas mileage
Only problem with adding more power is... more temptation to push the pedal more often... that equates to worse gas mileage
Whats funny is even with my blower I get somewhere around the same gas mileage.
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Joined: Nov 2001
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From: Vancouver Island, B.C. Canada
2005 smart cabrio; 2008 Mercedes-Benz B 200
underdrive
Just a dumb question:
Exactly which accessories are you underdriving? It'd be interesting to know.
Here are some possible consequences of underdriving accessory units that I can think of:
1. Alternator - insufficient output when using lots of electrical accessories, especially at idle
2. Water Pump - insufficient coolant circulation/overheating in summer, various engine speeds
3. Power Steering Pump - insufficient pressure/increased steering effort
4. A/C Compressor - insufficient cooling in hot weather.
For an engine to make measurable power gains from underdriving pullied accessory systems, like those listed above, by definition it has to lower their power consumption - ergo - lower the output of these accessory units. So what I'm asking, is by how much, and with what possible consequences?
Exactly which accessories are you underdriving? It'd be interesting to know.
Here are some possible consequences of underdriving accessory units that I can think of:
1. Alternator - insufficient output when using lots of electrical accessories, especially at idle
2. Water Pump - insufficient coolant circulation/overheating in summer, various engine speeds
3. Power Steering Pump - insufficient pressure/increased steering effort
4. A/C Compressor - insufficient cooling in hot weather.
For an engine to make measurable power gains from underdriving pullied accessory systems, like those listed above, by definition it has to lower their power consumption - ergo - lower the output of these accessory units. So what I'm asking, is by how much, and with what possible consequences?
Out Of Control!!
Joined: Nov 2001
Posts: 35,855
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From: Southern CA
As you mentioned, underdriving the accessories too much can lead to adverse affects. Simply put, we don't underdrive them to that extent 
We have hundreds of kits on BMW's and Mercedes, from street cars to race cars, and have not had a single problem with them.
We underdrive the water pump, power steering and alternator. All of the accessories are left at reliable levels, as we have designed this to be a kit that can be used on any street car. The only potential issue with our underdrive pulleys would be a large power drain, such as a large aftermarket stereo system. In this case, we would not recommend using the alternator pulley.
Underdrive the components is only one of the ways we get power. The pulleys are also made lighter, which in turn makes them easier to spin, and frees up more power.
We will never touch the air conditioning; these are luxury automobiles. It would be foolish, and we'd probably face a lynch mob for it!
Thanks,
Ben
We have hundreds of kits on BMW's and Mercedes, from street cars to race cars, and have not had a single problem with them.We underdrive the water pump, power steering and alternator. All of the accessories are left at reliable levels, as we have designed this to be a kit that can be used on any street car. The only potential issue with our underdrive pulleys would be a large power drain, such as a large aftermarket stereo system. In this case, we would not recommend using the alternator pulley.
Underdrive the components is only one of the ways we get power. The pulleys are also made lighter, which in turn makes them easier to spin, and frees up more power.
We will never touch the air conditioning; these are luxury automobiles. It would be foolish, and we'd probably face a lynch mob for it!
Thanks,
Ben
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Super Member
Joined: Jun 2002
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From: Encino
2002 C230K
well, at cruising speed, you will have no real difference in output from the accessories. I mean yes it will be there, but nothing that would be noticeable. And the underdrive pullies don't make massive amounts of power, they free up in the neighborhood of 10hp.
At most you would only underdrive the accessories by 30% and i believe it's only the AC and the alternator. So don't worry bout it.
EDIT: yeah, what Ben said.
At most you would only underdrive the accessories by 30% and i believe it's only the AC and the alternator. So don't worry bout it.
EDIT: yeah, what Ben said.
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MBWorld Fanatic!
Joined: Nov 2001
Posts: 3,861
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From: Jacksonville Florida
209/W210 Estate /W211 modded by MBENZNL
Power Pullies
I also Have The EVOSPORT Pullies and have Noticed a Nice gain in HP (Dyno Proven) Without any problems..No Charging problems, It Does NOT run Hot! I Drive Hard and have The A/C on all the time...Just a Great Mod and HPGain for the Money!
Senior Member
Joined: Feb 2002
Posts: 394
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From: Weston, FL
C230 Kompressor (02 Copupe)
hm...
yeah i mgettign the crank pulley soon.. just wondering..
since you said "As of now" does that means you guys have plans for developing UD pulleys for our coupes?
since you said "As of now" does that means you guys have plans for developing UD pulleys for our coupes?
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Joined: Sep 2002
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From: Ohio
2010 C300 4matic
You could talk to ASP and while they make the outer plane of the pulley bigger for the supercharger, they could make the inner plane smaller and it would underdrive all the other accessories.
