Underdrive Pulley

AlpineSwift · 12-27-2010, 03:41 AM

I know this subject has been talked about briefly in the past. I've tried doing some searching through the dusty old archives to no avail. Nothing specific about anything anywhere other than one guy looking into having something custom made from the stock parts.

I guess my question is, why the hell do the N54 and M3 guys get these and we don't? I would venture to guess our crank pulley is massively heavy and we could gain some pretty sizable numbers at the wheels.

Gavin, care to jump in on this?

forza1976 · 12-27-2010, 02:08 PM

This is a NO NO for the N54, let's just get that straight. Any of the options on the market don't take into account harmonic balancing that the stock pulley provides.

I gather the manufacturers for this type of mod just haven't spent the time on it because of little/light demand for the N52 engine. But I doubt gains would be huge.

DimSum · 12-27-2010, 02:32 PM

Quote:

Originally Posted by forza1976

This is a NO NO for the N54, let's just get that straight. Any of the options on the market don't take into account harmonic balancing that the stock pulley provides.

I gather the manufacturers for this type of mod just haven't spent the time on it because of little/light demand for the N52 engine. But I doubt gains would be huge.

+1. NO to after-market pullies.

Bimmer This · 12-27-2010, 05:25 PM

I don't think there is much of a aftermarket parts list for N52's.

Das.Euro · 12-27-2010, 06:18 PM

Dont wanna play with the harmonic balancer and have your crankshaft go outta whack lol plus im sure you would get some issues with alternator not providing enough power to juice up the electronics etc. Basically its just a lightened pulled thats all, less mass to turn, wouldnt bother with it. If i were you, i would look into a lightened flywheel

12-27-2010, 03:41 AM	#1
AlpineSwift Colonel 77 Rep 2,114 Posts Drives: 2008 335Xi Coupé Join Date: Feb 2010 Location: Castle Rock, CO iTrader: (3)	Underdrive Pulley I know this subject has been talked about briefly in the past. I've tried doing some searching through the dusty old archives to no avail. Nothing specific about anything anywhere other than one guy looking into having something custom made from the stock parts. I guess my question is, why the hell do the N54 and M3 guys get these and we don't? I would venture to guess our crank pulley is massively heavy and we could gain some pretty sizable numbers at the wheels. Gavin, care to jump in on this? __________________ E92 '08 335Xi 6AT - Cobb AP3 Tuned by MAC Autosport, Original Prototype Xi DOCRace 6266 Single Turbo Swap, VRSF CP w/Synapse BOV, VRSF 7" FMIC, BMS Cowl, H&R Coilovers, Renn Motorsport RS-51's, Stoptech Stage 2 Slotted, xHP Stage 3, Earl's Racing Oil Cooler, Turner Boost Gauge, M3 Lip Spoiler. Standing Mile Record Holder for Xi over a mile high: 168.2MPH @ 5512'; The Colorado Mile hosted by The US Mile.
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12-27-2010, 02:08 PM	#2
forza1976 Major General 3398 Rep 6,589 Posts Drives: BMW Join Date: Aug 2007 Location: 49417 and 60610 iTrader: (13) Garage List 2022 BMW M3X [10.00]	This is a NO NO for the N54, let's just get that straight. Any of the options on the market don't take into account harmonic balancing that the stock pulley provides. I gather the manufacturers for this type of mod just haven't spent the time on it because of little/light demand for the N52 engine. But I doubt gains would be huge.
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12-27-2010, 05:25 PM	#4
Bimmer This Major General 99 Rep 6,473 Posts Drives: 2007 BMW 335i Join Date: Nov 2008 Location: Westminster iTrader: (3)	I don't think there is much of a aftermarket parts list for N52's.
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12-27-2010, 06:18 PM	#5
Das.Euro Banned 9 Rep 432 Posts Drives: 07 328XI- Montego Blue Join Date: Oct 2010 Location: NNJ iTrader: (3)	Dont wanna play with the harmonic balancer and have your crankshaft go outta whack lol plus im sure you would get some issues with alternator not providing enough power to juice up the electronics etc. Basically its just a lightened pulled thats all, less mass to turn, wouldnt bother with it. If i were you, i would look into a lightened flywheel
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