Supercharger Pulley
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Joined: Sep 2022
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From: Ohio
2005 S55 AMG, 2001 SL500
Supercharger Pulley
I recently bought an '05 S55 AMG with a RaceIQ Stage II tune and an 83mm fixed pulley installed and am considering reverting back to the OEM clutched pulley that came with the car. Question is this: If I revert to the OEM pulley does the tune need to be reverted as well? Thanks for your help, CICBarkeep
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'03 S55 (79K miles)
Probably
The smaller pulley would have had the effect of increasing the air input. A resultant increase of fuel would have been called for to keep the air:fuel ratio right, which is why prior owner got a tune.
Decreased air would beg for decreased fuel, which is supplied by the injectors which would be controlled by the ECU, that would have been tuned away from stock levels.
so, going back to OE air would require going back to OE air:fuel ratios and thereby stock tune.
Decreased air would beg for decreased fuel, which is supplied by the injectors which would be controlled by the ECU, that would have been tuned away from stock levels.
so, going back to OE air would require going back to OE air:fuel ratios and thereby stock tune.
Last edited by GrepAwk; Oct 23, 2022 at 10:32 PM.
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Joined: Sep 2022
Posts: 155
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From: Ohio
2005 S55 AMG, 2001 SL500
Supercharger Pulley
@GrepAwk Thanks for the prompt response and confirmation of my suspicions. I appreciate what the PO was after, but the supercharger rattle at idle just rubs me the wrong way. I guess I'm left with two options. Clutched 83mm pulley or revert to stock configuration across the board. Any thoughts?
Thanks again.
Thanks again.
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'06 MB S55 AMG; '04 Audi Allroad 4.2; '05 BMW M3 Conv.; '92 MB 500E
@GrepAwk Thanks for the prompt response and confirmation of my suspicions. I appreciate what the PO was after, but the supercharger rattle at idle just rubs me the wrong way. I guess I'm left with two options. Clutched 83mm pulley or revert to stock configuration across the board. Any thoughts?
Thanks again.
Thanks again.
I am running the same setup, and knowledgeable people have told me they’d rather have a fixed pulley (linear power, no clutching engagement). It’s all preference in my opinion, but if the rattle is that big a problem (trust me, I understand, I’d have a fixed one if it wasn’t for the rattle), the simplest thing to do would be a new 83mm clutched pulley — same belt, same tune.
I’m sure PO gave you the stock tune file (or will if you just ask him), so you have that option available as well.
GL
maw
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From: Ohio
2005 S55 AMG, 2001 SL500
Part of the fixed pulley install included wiring a resistor "into the harness side of the supercharger plug so that clutch and ECU will think the clutch is engaged at all times." I'm assuming that resistor will need to be removed with the installation of a clutched pulley but have no clue where to look or how to go about deleting it. Any help appreciated.
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w220 S55 AMG 2004
Part of the fixed pulley install included wiring a resistor "into the harness side of the supercharger plug so that clutch and ECU will think the clutch is engaged at all times." I'm assuming that resistor will need to be removed with the installation of a clutched pulley but have no clue where to look or how to go about deleting it. Any help appreciated.
