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Discussion Starter #1
I am thinking about installing switch in the dashboard. With this switch i will turn off (or on) supercharger when i wont need so much power. Because even when supercharger is not making efficient BOOST (cruising with little throttle push) it is using from 10-30 PS. Because supercharger run ALWAYS when car is moving (diference is only if bypass opens or not). Clutch turn supercharger OFF ONLY in standstill at idle.
So if we cruise at 70 km/h with just a little throttle pedal push, supercharger IS RUNNING (so it is using power from engine), but bypass opens (so superchrger is running, but efficient BOOST is bleed out). So supertcharger is turning with no use. It is just making noise and use fuel. If we turn of supercharger (with this switch), i think we can save a lot of fuel, supercharger life and engine is much quiter. When you need all power, just turn switch on.

What do you think?
 

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1998 SLK 230
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supercharger comes on at ~2500rpm.... i dont know what gear are u driving in but most of the daily driving is in avg around 2000rpm - 2200rpm (60-80km/h). on the freeway when you are doing 100km/h it sits about 3000rpm but when ur on the freeway ur fuel economy is hell better than city driving anyway...


dont think its a good idea....... as the clutch is constantly monitored from engine management. if u d/c power to it then it will set a fault code... and turning it back "on" may or may not take the fault code away. this will disable the supercharger system..... it wont boost as a safety feature because it belives something has failed.

more than likely it will keep the fault code until next restart of the car or clearing it with a code reader.

turing it on and off when its not designed to be on / off might send electrical spikes/surges and destroy or fry the management controller running it.

not worth it.
 

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Discussion Starter #3 (Edited)
supercharger comes on at ~2500rpm.... i dont know what gear are u driving in but most of the daily driving is in avg around 2000rpm - 2200rpm (60-80km/h). on the freeway when you are doing 100km/h it sits about 3000rpm but when ur on the freeway ur fuel economy is hell better than city driving anyway...


dont think its a good idea....... as the clutch is constantly monitored from engine management. if u d/c power to it then it will set a fault code... and turning it back "on" may or may not take the fault code away. this will disable the supercharger system..... it wont boost as a safety feature because it belives something has failed.

more than likely it will keep the fault code until next restart of the car or clearing it with a code reader.

turing it on and off when its not designed to be on / off might send electrical spikes/surges and destroy or fry the management controller running it.

not worth it.

Now lets make things clear, because obviosly you are mixing/dont know about things/dont undersatnd what i am trying to do about supercharger/clutch/rpm etc;

1. Supercharger clutch kick in at 2000 rpm when vehicle is at standstill (0 km/h)
1a. If your clutch kick in at 2500 then it is something wrong with your clutch or with your clutch managment (controler)
2. Supercharger clutch kick in almost at idle rpm when vehicle start moving (doesnt matter if it is moving by engine power, or by downhill without gas pedal push), and STAY IN till vehicle almost stop (doesnt matter what rpm and engine load you make, clutch stays in ALWAYS until wehicle stop).
3. When you are moving, it doesnt matter what rpm you are running; the clutch is ALWAYS engaged, so blower is ALWAYS spinning, BUT
4. Bypass valve dictate if boost is efective or boost is bleeded out

So:

5. When you are cruizing let say at cca 2500 rpm at 100 km/h with just a little gas pedal push, kompressor is running (bypasss valve open) without any profit for us. It just guzzle more gas and it takes away cca 10 PS when cruizing at 2500 rpm, and make engine more loud. And i dont even mentioned kompressor prolonged life with this feature.

Tomorrow i will try to do it and then i will report. Today i manualy disconect clutch plug and run without kompressor for all day. Then i conect the clutch again and run with kompressor. Without problems, without error code.

I will see tomorow..Someone on SLKboard (Our German forum) already did this , but i could not find his posts....

The only problem i can see is making some sort of (maybe simple) electronic box, which will make DME think that kompresor clutch is in even when it will not be in (because we will turn it of by the switch when we wont use kompressor).
 

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Now lets make things clear, because obviosly you are mixing/dont know about things/dont undersatnd what i am trying to do about supercharger/clutch/rpm etc;

1. Supercharger clutch kick in at 2000 rpm when vehicle is at standstill (0 km/h)
1a. If your clutch kick in at 2500 then it is something wrong with your clutch or with your clutch managment (controler)
2. Supercharger clutch kick in almost at idle rpm when vehicle start moving (doesnt matter if it is moving by engine power, or by downhill without gas pedal push), and STAY IN till vehicle almost stop (doesnt matter what rpm and engine load you make, clutch stays in ALWAYS until wehicle stop).
3. When you are moving, it doesnt matter what rpm you are running; the clutch is ALWAYS engaged, so blower is ALWAYS spinning, BUT
4. Bypass valve dictate if boost is efective or boost is bleeded out

So:

5. When you are cruizing let say at cca 2500 rpm at 100 km/h with just a little gas pedal push, kompressor is running (bypasss valve open) without any profit for us. It just guzzle more gas and it takes away cca 10 PS when cruizing at 2500 rpm, and make engine more loud. And i dont even mentioned kompressor prolonged life with this feature.

Tomorrow i will try to do it and then i will report. Today i manualy disconect clutch plug and run without kompressor for all day. Then i conect the clutch again and run with kompressor. Without problems, without error code.

I will see tomorow..Someone on SLKboard (Our German forum) already did this , but i could not find his posts....

The only problem i can see is making some sort of (maybe simple) electronic box, which will make DME think that kompresor clutch is in even when it will not be in (because we will turn it of by the switch when we wont use kompressor).

I think the 230 kompressor is a reliable & efficient car as it is and dont think its really worth the trouble to do this... just my opinion.. btw, mind posting some pictures of your car?? seems like a really nice one from the details in your sig...
 

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Discussion Starter #5
I think the 230 kompressor is a reliable & efficient car as it is ...

So why pullyes? :)Why lower suspension?:) Why other goodies? :)

Every mod is worth it...but different for each other.:thumbsup:


About my car; Thnaks for comments (Btw. your car is also REALLY special!!!) I will post pictures of my lady , just let me do some foto shooting...:thumbsup::)
 

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1998 SLK 230
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Now lets make things clear, because obviosly you are mixing/dont know about things/dont undersatnd what i am trying to do about supercharger/clutch/rpm etc;

1. Supercharger clutch kick in at 2000 rpm when vehicle is at standstill (0 km/h)
1a. If your clutch kick in at 2500 then it is something wrong with your clutch or with your clutch managment (controler)
2. Supercharger clutch kick in almost at idle rpm when vehicle start moving (doesnt matter if it is moving by engine power, or by downhill without gas pedal push), and STAY IN till vehicle almost stop (doesnt matter what rpm and engine load you make, clutch stays in ALWAYS until wehicle stop).
3. When you are moving, it doesnt matter what rpm you are running; the clutch is ALWAYS engaged, so blower is ALWAYS spinning, BUT
4. Bypass valve dictate if boost is efective or boost is bleeded out

So:

5. When you are cruizing let say at cca 2500 rpm at 100 km/h with just a little gas pedal push, kompressor is running (bypasss valve open) without any profit for us. It just guzzle more gas and it takes away cca 10 PS when cruizing at 2500 rpm, and make engine more loud. And i dont even mentioned kompressor prolonged life with this feature.

Tomorrow i will try to do it and then i will report. Today i manualy disconect clutch plug and run without kompressor for all day. Then i conect the clutch again and run with kompressor. Without problems, without error code.

I will see tomorow..Someone on SLKboard (Our German forum) already did this , but i could not find his posts....

The only problem i can see is making some sort of (maybe simple) electronic box, which will make DME think that kompresor clutch is in even when it will not be in (because we will turn it of by the switch when we wont use kompressor).
1. thats correct

1a. yes there is something wrong with my controller - i am getting a new one.

2. i dont know what you seem to be saying here? the whole purpose of the clutch is to turn the supercharger OFF at idle to save fuel economy... it does not engage below 2000rpm. it does not engage at idle.

3. blower is not always spinning, only 2000rpm +. get a LED & resistor and pop it in parallel to the line which runs the electromagnetic clutch. the LED will light up when the clutch engages. see for yourself.

4. bypass does control/maintain boost levels. it does not dictate maximum boost. the pulley does.

5. for me fuel economy with no charger aint too much different to with the charger. i agree its like running the air con all the time.

its been talked about before on the forums. but let us know how you go.

cheers
 

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I doubt that you'll save much fuel. With the bypass open, the air charge is recirculated back to the blower inlet, so there is not much load on the engine. When the bypass is closed and air is being forced into the cylinders through the intercooler, that loads the supercharger.

Not sure why you want/need electronics to fool the engine computer. You experiment proves it is not necessary, doesn't it?
 

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Discussion Starter #8 (Edited)
1. thats correct

1a. yes there is something wrong with my controller - i am getting a new one.

2. i dont know what you seem to be saying here? the whole purpose of the clutch is to turn the supercharger OFF at idle to save fuel economy... it does not engage below 2000rpm. it does not engage at idle.

3. blower is not always spinning, only 2000rpm +. get a LED & resistor and pop it in parallel to the line which runs the electromagnetic clutch. the LED will light up when the clutch engages. see for yourself.

4. bypass does control/maintain boost levels. it does not dictate maximum boost. the pulley does.

5. for me fuel economy with no charger aint too much different to with the charger. i agree its like running the air con all the time.

its been talked about before on the forums. but let us know how you go.

cheers
2. If Euro and American/Australian model are not different (not mention your clutch controler is not working properly), than YOU are wrong; I have try with LED (it shines always when vehicle in move) and also i HEAR supercharger work ALWAYS when vehicle is in move (remember, i have 2 pullyes, so beleave me i can HEAR when SC runns). And it is well known fact in Europe that SC runs always when vehicle in move (speed is larger than cca 2 km/h and rpm is just a little larger than idle rpm). Purpose of clutch is to turn the SC down ONLY AT IDLE, not to turn it down/ON while driving. And like i said,clutch turns on instantly when vehicle start to move and STAY IN until vehicle stop; no mattre what load or rpm you are driving between.

3.Wrong again mate (again-only if our models really differs and not to mention that your clutch controler is not working properly); SC spin ALWAYS when vehicle in move;

4. I did NOT written that bypass make (dictate) max.boost. I said that when vehicle is in move, bypass dictate when boost is effective /bleed out; So you dont need clutch to turn on/off between vehicle move. Bypass is there to do that (actually to bleed out BOOST, which is practycaly the same as turn SC off by clutch). Clutch is there only to turn SC off only at idle and vehicle stand still.

5. You can save relatively a lot of fuel with SC turn down, even when driving with little load (bypass open), but main thing is to prolong SC life and lower engine noise AND at the end save fuel.
 

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Discussion Starter #9
I doubt that you'll save much fuel. With the bypass open, the air charge is recirculated back to the blower inlet, so there is not much load on the engine. When the bypass is closed and air is being forced into the cylinders through the intercooler, that loads the supercharger.

Not sure why you want/need electronics to fool the engine computer. You experiment proves it is not necessary, doesn't it?

You are wrigt about 1. part; There is LESS load on engine when bypass is open, but SC still use at least 5 PS then.

I want electronics to fool the DME because i am afraid that i can damage DME if i constantly (daily) turn on/off Sc between riding. I think you are reallly expert in electronic, so do you have any advice?
 

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Not sure why you want/need electronics to fool the engine computer. You experiment proves it is not necessary, doesn't it?
DickB......was the experiment you referred to.......Snogard disconnected the S/C clutch for a day and got no DTC or problems when reconnected

.....so there is no need to fool the ECU

I really would expect a P0806 DTC to be set eventually......and the whole performance system shut down

....perhaps the number of cycles is more important than the length of time.....would still expect a pending code

I can see some merits in a Kompressor switch for long trips....but feel it would need to 'fool' the ECU to prevent DTCs and S/C system shut down

I also would be very interested to hear DickB's ideas for a kompressor switch and possibly electronic boost control..... for SLK's with a clutch and bypass......

Cheers

David
 

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Discussion Starter #11 (Edited)
I can see some merits in a Kompressor switch for long trips....but feel it would need to 'fool' the ECU to prevent DTCs and S/C system shut down
To fool ECU i have 2 thoughts;
1. Maybe i should take another SC clutch and use it as a dummy (not connected mechanicly to SC) and electricaly connect it paralely with second clutch (which IS mechanicaly conected to SC). Then we can switch OFF second (original) clutch with switch inside the cabin, and ECU wont notice that, because dummy clutch will still be "on".
The question is if ECU can withstand double amps (from double SC clutch) when both clutches will be ON (this happens when real clutch is turn ON by my switch, and dummy clutch is turn on ba ECU).

Or:

2. Maybe take another SC clutch and use it as dummy clutch (not mechanicaly connected to SC, just electricaly connected to ECU. Original clutch on SC will be permanently (thruu ON/OFF switch in cabin) connected directly to 12V. So ECU will control dummy clutch, and you (i) can control (with ON/OFF switch in cabin) "real" SC clutch. Downside of this option is that case kompressor will work nonstop (will not declutch at idle) or never. So it will not automaticaly declutch at idle.

Dick, what do you think about that idea?
 

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I imagine the ECU looks at a number of factors to decide everything is working ok..............this is why you get a P0803 code when it doesn't get the reading it expects from the MAF at a particular setting of the bypass valve & throttle body................

............so a P0806 DTC may be set if the boost the ECU expects is not registered by the MAF with a clutch substitute if the S/C is not being driven........

.....if it gets a reading from the clutch circuit that makes it think it is working ok, then it will probably blame the bypass valve and set a P0803 DTC instead..............

............so I doubt a substitute clutch or resistance will 'fool' the ECU :(
 

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Discussion Starter #13
I imagine the ECU looks at a number of factors to decide everything is working ok..............this is why you get a P0803 code when it doesn't get the reading it expects from the MAF at a particular setting of the bypass valve & throttle body................

............so a P0806 DTC may be set if the boost the ECU expects is not registered by the MAF with a clutch substitute if the S/C is not being driven........

.....if it gets a reading from the clutch circuit that makes it think it is working ok, then it will probably blame the bypass valve and set a P0803 DTC instead..............

............so I doubt a substitute clutch or resistance will 'fool' the ECU :(

Hmm, let say this way; If you shave blades from both SC roots (so SC will spin but make no boost) and everything else left the same , would DME trigger a fault code?
Only if it have saved boost map which tells ecu what boost to expect at engaded clutch at specific rpm/load (throttle position). But if this is the case then higly pullyed (in my case kompressor/engine rpm ratio is 2,53, so MUCH higher than stock) engine would also trigger a fault code, but it would not!

I think with double clutch i could fool DME; in fact one of our German members already did this with succes, but only as experiment for few days. He did not notice any downsides.
 

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i thought all 98,99,2000 slk had clutch and this was to prolong SC life, not to increase fuel econ? then they changed SC design to allow full time SC running without any clutch? so tell me, if you can buy a rebuilt/used SC for 200$ USD, and the car already gets 30 mpg then why the hell would you risk any damage/waste time and $ trying to re-invent the wheel?
 

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Discussion Starter #15 (Edited)
i thought all 98,99,2000 slk had clutch and this was to prolong SC life, not to increase fuel econ? then they changed SC design to allow full time SC running without any clutch? so tell me, if you can buy a rebuilt/used SC for 200$ USD, and the car already gets 30 mpg then why the hell would you risk any damage/waste time and $ trying to re-invent the wheel?
Obviously you are NOT reading what i (we) have written;

This mod is NOT just for fuel save, but also and MOSTLY for kompressor (specialy for pulleyed ones) prolonged life AND for less engine noise (pulleyed kompressors are known for noisy running). Now you tell me WHY should i let my kompressor run on freeway at 130 km/h on tempomat (cruise control), if there is NO NEED to? It just guzzles more fuel, make more noise and slowly destroying kompressor bearings. Remember at that conditions (freeway-little load-130 km/h-tempomat cruising- SC IS running, but bypass is letting out all boost, so it is the same as if i turn SC of; Difference betwen SC OFF and SC run (and boost bleed out) is less noise and better fuel economy and prolonged SC life.

I didnt mentioned yet, but all PreFl pulleyed SLKs have hasitation problems in cold phase of running (first 2 minutes of cold run) because air/fuel ratio is (because of higher boost) too lean. Now if i can turn kompressor of in cold running phse, i will get rid of hesitation.

I hope you understand now why i wont to turn SC OFF when i dont need it and DME "forget" to turn it off.

Mercedes went to modified system (with no clutch), because it put in DIFFERENT (M45) SC which takes less HP from engine (so lower fuel consumption) and runs with less noise. Downside of M45 SC is less BOOST capability than M62 SC can offer. All bigger Superchargers still uses clutch! Only when really small SC is in game they can afford system with no clutch.

P.S. Did i mentioned that Nissan 350Z GT-S uses THE SAME SYSTEM (switchable Novidem Supercaharger)?
Nissan 350Z GT-S Concept - E46Fanatics

Citat from another 350Z GT-S article:
"One further refinement to the installation is the fitment of an electrically operated clutch between the supercharger and the engine drive belt which automatically disconnects the ’blower at idle to save fuel.

More significantly, a switch on the centre console just ahead of the gear lever allows the owner to actuate the clutch and shut off the ’blower at will. In other words, an owner could keep road performance to standard 350Z levels during the working week and, by flipping a switch, unleash the full performance potential of the supercharger to provide something extra for the weekend"
Here is link to full article: THE 350Z GT-S: NISSAN’S WEEKEND WARRIOR

Here is one ven more interesting article about switchable supercharger in 350Z GT-S: Nissan 350Z GT-S prototype (2006 model) - First Drives | Reviews | MSN Cars UK

Here is picture of switch:


And link with full article: Driving some hot Nissan concepts that the U.S. can't have



So, Mr. @[email protected] i hope now you can fully understand why i am "inventing a wheel" here....
 

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98 SLK230, 05 C-240T
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To fool ECU i have 2 thoughts;
1. Maybe i should take another SC clutch and use it as a dummy (not connected mechanicly to SC) and electricaly connect it paralely with second clutch (which IS mechanicaly conected to SC). Then we can switch OFF second (original) clutch with switch inside the cabin, and ECU wont notice that, because dummy clutch will still be "on".
The question is if ECU can withstand double amps (from double SC clutch) when both clutches will be ON (this happens when real clutch is turn ON by my switch, and dummy clutch is turn on ba ECU).

Or:

2. Maybe take another SC clutch and use it as dummy clutch (not mechanicaly connected to SC, just electricaly connected to ECU. Original clutch on SC will be permanently (thruu ON/OFF switch in cabin) connected directly to 12V. So ECU will control dummy clutch, and you (i) can control (with ON/OFF switch in cabin) "real" SC clutch. Downside of this option is that case kompressor will work nonstop (will not declutch at idle) or never. So it will not automaticaly declutch at idle.

Dick, what do you think about that idea?
Snogard:

Just wire the setup with a double throw switch, so that when it's in one position the original clutch is activated and when it's in the other position the dummy is activated. You probably don't even need a second clutch. Just an electrical load (a resistor would do) equivalent to the resistance across the supercharger clutch coil should suffice.

ERFOY
 

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Obviously you are NOT reading what i (we) have written;

This mod is NOT just for fuel save, but also and MOSTLY for kompressor (specialy for pulleyed ones) prolonged life AND for less engine noise (pulleyed kompressors are known for noisy running). Now you tell me WHY should i let my kompressor run on freeway at 130 km/h on tempomat (cruise control), if there is NO NEED to? It just guzzles more fuel, make more noise and slowly destroying kompressor bearings. Remember at that conditions (freeway-little load-130 km/h-tempomat cruising- SC IS running, but bypass is letting out all boost, so it is the same as if i turn SC of; Difference betwen SC OFF and SC run (and boost bleed out) is less noise and better fuel economy and prolonged SC life.

I didnt mentioned yet, but all PreFl pulleyed SLKs have hasitation problems in cold phase of running (first 2 minutes of cold run) because air/fuel ratio is (because of higher boost) too lean. Now if i can turn kompressor of in cold running phse, i will get rid of hesitation.

I hope you understand now why i wont to turn SC OFF when i dont need it and DME "forget" to turn it off.

Mercedes went to modified system (with no clutch), because it put in DIFFERENT (M45) SC which takes less HP from engine (so lower fuel consumption) and runs with less noise. Downside of M45 SC is less BOOST capability than M62 SC can offer. All bigger Superchargers still uses clutch! Only when really small SC is in game they can afford system with no clutch.

P.S. Did i mentioned that Nissan 350Z GT-S uses THE SAME SYSTEM (switchable Novidem Supercaharger)?
Nissan 350Z GT-S Concept - E46Fanatics

Citat from another 350Z GT-S article:
"One further refinement to the installation is the fitment of an electrically operated clutch between the supercharger and the engine drive belt which automatically disconnects the ’blower at idle to save fuel.

More significantly, a switch on the centre console just ahead of the gear lever allows the owner to actuate the clutch and shut off the ’blower at will. In other words, an owner could keep road performance to standard 350Z levels during the working week and, by flipping a switch, unleash the full performance potential of the supercharger to provide something extra for the weekend"
Here is link to full article: THE 350Z GT-S: NISSAN’S WEEKEND WARRIOR

Here is one ven more interesting article about switchable supercharger in 350Z GT-S: Nissan 350Z GT-S prototype (2006 model)Â*-Â*First Drives | Reviews | MSN Cars UK

Here is picture of switch:


And link with full article: Driving some hot Nissan concepts that the U.S. can't have



So, Mr. @[email protected] i hope now you can fully understand why i am "inventing a wheel" here....
sorry mate but the wheel was already invented. all i am wondering is why try to increase fuel econ on a vehicle that already is known for good econ? youre saving pennies and not saving the world even if it works, and the wear issue to me isnt a big deal either since i see new or used SC for pretty cheap. also the noise? is it really loud? my 230 is pulleyed and it makes almost no SC whine and if it did i might enjoy that anyway! i do feel that if the system isnt loaded then why run the bearings but i also think that the bearings that spin while clutch is disengaged are going to wear and need replaced sometime anyway, and the belt also is sucking fuel the same either way, so why not just run the sucker? these benz engineers might not be working with our best interests always but they are pretty sharp folks. i think youre more interested in a "turbo" button like my dads old ibm 386 had. ;) (if you use one of these buttons you owe me a dollar!)
 

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Discussion Starter #18 (Edited)
Snogard:

Just wire the setup with a double throw switch, so that when it's in one position the original clutch is activated and when it's in the other position the dummy is activated. You probably don't even need a second clutch. Just an electrical load (a resistor would do) equivalent to the resistance across the supercharger clutch coil should suffice.

ERFOY
Thanks for advice man! The question is if this double switch will be quick enough so DME wont notice any change? What do you think? Tommorow i will try that becuse eather way that system would be the most elegant if i could make it to work...
 

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Discussion Starter #19
sorry mate but the wheel was already invented. all i am wondering is why try to increase fuel econ on a vehicle that already is known for good econ? youre saving pennies and not saving the world even if it works, and the wear issue to me isnt a big deal either since i see new or used SC for pretty cheap. also the noise? is it really loud? my 230 is pulleyed and it makes almost no SC whine and if it did i might enjoy that anyway! i do feel that if the system isnt loaded then why run the bearings but i also think that the bearings that spin while clutch is disengaged are going to wear and need replaced sometime anyway, and the belt also is sucking fuel the same either way, so why not just run the sucker? these benz engineers might not be working with our best interests always but they are pretty sharp folks. i think youre more interested in a "turbo" button like my dads old ibm 386 had. ;) (if you use one of these buttons you owe me a dollar!)

1. First thing that you obviously dont (wont to) understand is fact that SC is running ALL THE TIME when vehicle is moving (also the clutch is engaged for that same time). Difference is only if bypass open or close (depends on load, rpm and throttle position). So when it is open (most of driving time), SC still spin (with no use, just to make annoying noise) and use AT LEAST 5-10 HP (even more at higher rpm). Now those 10 horses use fuel. And if this is 1 liter/100 km LESS than with SC spinning (with no use i repeat), than just at that aspect that is AWSOME work. Not just from my pocket view, but also for inviroment good.

2. Noise. I dont know about your car, but all pullyed PreFl 230K are loud. Specially double pulleyed (like my). And if i have a chance to turn down this ugly noise when i dont need it, why woudnt i?

3. SC prolonged life; I bought brand new SC last month. Now i wont this SC to last at least 3 years (remember my SC rpm to engine rpm ratio is 2,54 which is VERY high). I dont wont to buy another SC next year (new or used, doesnt matter). Now why wouldnt i prolonged my NEW SC life, if i could? I know that my double pulleyed SC is on heavy load, so why not put of his back at least a little of that load?

4. Cold hesitate running; That is the thing that bother me most,and that is the thing that no user of PreFl pulleyed 230K can avoid. With this feature (to turn SC OFF while cold running) i can get rid of that very annoying hesitation , which is in my case (double pulleyed SC) even more annoying.

5. With that feature i can get rid of that sily, turbine like whinning in cold phase. Now if you like that sound, that is you, but i REALLY dont like when i drive of at my job park place and people look at me and at my car like they think that my engine will blow up in next second...

6. You are wright, the wheel is already invented here (Nissan 350Z GT-S) and its users gladly use this feature. If you have read all the articles i linked in previous post, you can see that it have THE SAME SYSTEM (switchable SC with electromagnetical clutch) and also you can see that users of that Nissan often turn SC OFF. Of course they do, because they have AT LEAST 3 GOOD REASONS to turn SC off, and i personaly have at least 5 reasons to turn SC off.

7. This thread is to discuss HOW to (make SC switchable) and NOT WHY. So please if you have no advices and knolidge about that, ignore this thread. Thank you very much.
 

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1998 SLK 230
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what would happen if someone decided to switch the "system" on at an non approriate RPM? (acidently or not knowlingly)....... say it went on at 3000+3500rpm on a pullied charger.

that would cause quite a shock and stress on the components on the pulley system and possibly damage your belt...
 
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