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Let's look at the alternator
Cruising at constant rpm
Turn lights on
You don't have to speed up to meet demand
It is variable output load dependent
All kind of stuff on; lights, stereo, seat heaters, battery charging , etc
Output 100 A
If you slow down a bit do you notice ? No
Power = 14 vdc x 100 a = 1400 w ~ 2 hp
Electric machines are pretty efficient
Let's say 3 hp in to make the 2 hp out
Will slowing the alternator down reduce the P required ?
No...first the alt pulley << drive pulley, eyeballing 4:1
Engine 600 alt 2400
Slowing it down 5 or 10% means nothing re: alt eff
Will P in be reduced by slowing it down ?
The load takes the same 100 a and v stays regulated at 14 vdc
So how can it be slowed down and make the same power ?
P = torque x rotational speed
If you slow it down the torque to drive increases
And the engine supplies the same power
Just as if you varied rpm from 2000 to 2400 the power consumption is constant
It is the analogy of a variable diameter alt pulley
It can change diameter but power remains the same v and i are constant
Net power is constant
To save power turn the seat heaters off lol
Can you please send the dyno results to the cars you tested on?
This^
I'm part of the group buy but have not sent my payment yet. I'm still nervous about everything that is being said here and would like EuroCharged to step in and respond to some of the claims that are being made. I don't think ANYONE is going to be happy if we come back 6mth/year from now claiming that this damaged someones car.....
^ he's got a point. Talked to my mechanic about this and he doesn't exactly know how a pulley will give you more horsepower. I'm probably going to pass on this. Terribly sorry
It's a lighter pulley and it spins the accessories slower. Just a heads up for you guys that are buying the pulley. You need to lock your flywheel in place to put the pulley on. And, since eurocharged doesn't supply the special tool to go with it, you will most likely need to go to the dealer or jam your flywheel with a crowbar... Good luck
Do you guys actually think that an authorized MB dealership will put on this pulley in place of the OEM?
If so then count on seeing your engine warranty tossed out with that days garbage.
Not saying anything about the product but MB will not honour any warranty left on the engine or possibly the whole drivetrain with the addition of a rotating mass change.
Do you guys actually think that an authorized MB dealership will put on this pulley in place of the OEM?
If so then count on seeing your engine warranty tossed out with that days garbage.
Not saying anything about the product but MB will not honour any warranty left on the engine or possibly the whole drivetrain with the addition of a rotating mass change.
I guess it would be worth it if you run the car continually over 4 grand, but as seen in the dyno run the stock setup gives more HP and torque up to 3750 which in high gear is 120mph +. Considering the car runs at 80mph at 2000rpm.
Maybe the ingenieur could explain why the stock rotating mass is superior below 3750rpm and just a whisper more at 4250rpm.
This qualifies for the most un-informative sales pitch in the recorded history of this forum.
Really Eurocharged, if you are going to bring something new to the table. At least be straight forward with the info. This is not the first time I have raised this issue. There are actually members on here who have real world experience with pulleys and other performance upgrades that have legitimate questions on your product.
We are all interested in the pulley, but with the lack of info and to me the sheer unwillingness to really offer some insight on this product. It's making me wonder if this is worth the 1K investment when all said and done.
I really want to support you guys, as I do believe in tuners who push the platform, were a rare group of owners. You guys gotta step up your game.
This qualifies for the most un-informative sales pitch in the recorded history of this forum.
Really Eurocharged, if you are going to bring something new to the table. At least be straight forward with the info. This is not the first time I have raised this issue. There are actually members on here who have real world experience with pulleys and other performance upgrades that have legitimate questions on your product.
We are all interested in the pulley, but with the lack of info and to me the sheer unwillingness to really offer some insight on this product. It's making me wonder if this is worth the 1K investment when all said and done.
I really want to support you guys, as I do believe in tuners who push the platform, were a rare group of owners. You guys gotta step up your game.
We had our other dealer send us their before/after dyno pulls of the pulley and this is what they received. The down low rpm issue on the first graph was because of when the pull was started. The second graph has the runs starting at the same rpm so the torque and hp are more consistent this time.
So if I am reading the graphs correctly then there is no gain till after 5000rpm?
How do you come to that conclusion...?
Unless I am reading it incorrect, the pulley (red line) is showing a gain over stock (blue line) throughout the entire curve...
How do you come to that conclusion...?
Unless I am reading it incorrect, the pulley (red line) is showing a gain over stock (blue line) throughout the entire curve...
Alittle unsure about reading the graphs and the lack of input buy EC. I am more of a track and time slip guy. I see what you are saying now, but the first graph shows the lines almost matching until about 5krpm
Alittle unsure about reading the graphs and the lack of input buy EC. I am more of a track and time slip guy. I see what you are saying now, but the first graph shows the lines almost matching until about 5krpm
this was because of incorrect dynoing or if not incorrect then not dynoing consistently. these were on a dyno dynamics which is a load bearing dyno and there are many things that have to be done to run consistently. the first dyno graph was not consistent through both runs because of when the run was started
Alittle unsure about reading the graphs and the lack of input buy EC. I am more of a track and time slip guy. I see what you are saying now, but the first graph shows the lines almost matching until about 5krpm
Originally Posted by sales@eurocharged.com
this was because of incorrect dynoing or if not incorrect then not dynoing consistently. these were on a dyno dynamics which is a load bearing dyno and there are many things that have to be done to run consistently. the first dyno graph was not consistent through both runs because of when the run was started
And in any event, it was making power at 3700 not 5000 in the first graph.
Where a pulley should be noticed is more down low and heading into the mid range power band, as you get to the top end and power starts tapering off you probably wont notice it as much. Where you will notice the performance gain may not necessarily be in the power so much, but how much quicker the rpms will elevate due to the less rotational mass and weight reduction.
Addressing the concerns about underdriving the accessories, there is a safety margin built into the Mercedes system that allows us some room to play around. The smaller crank pulley not only adds more RPM to the engine, it also frees up some of the extra power used by the accessories. Driving these accessories at higher rpm is a waste of energy, running it at a much higher rate than it needs to for optimum effectiveness.
This is energy which could be put toward acceleration instead. After extensive testing, there haven't been any negative effects.
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