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• S14 Harmonic Balancer
• Trigger wheel and VR sensor mounting bracket from Massive Brakes

Harmonic Balancer

Some people turn down the front of the S14 crankshaft to fit the M10 pulley, this is especially popular for making cheater cranks to get around rules the prevent stroker motors.  I personally don't like this idea.  I don't like the idea of turning down the crankshaft when the S14 pulley is readily available.  The S14 pulley is also a harmonic balancer, not just a simple crank pulley like the M10.  Some people say the engine will run fine without the balancer but I figure that BMW went through the added expense of using a harmonic balancer for a good reason so I will be using it.

The S14 pulley's oil seal surface is noticeably larger in diameter than the M10 pulley.  To get the S14 pulley to fit on an M10 you need to enlarge the hole in the lower timing cover to use the S14 front oil seal.  This is a simple machining job and cheaper than having the crankshaft modified.  Here is the M10 and the S14 crankshaft pulleys.

Crank Trigger Wheel and Position Sensor

Another issue I needed to resolve was what to do about my crank trigger wheel and position sensor.  I will be using the S14 harmonic balancer.  The pictures below show my current M10 crank pulley with toothed wheel next to the S14 pulley.  You can see that the inner-most S14 pulley is exactly where my current toothed wheel is located.  This means I cannot use my current sensor bracket as the toothed wheel will need to be located closer to the lower timing cover than my current bracket will allow.

I was told by a friend of mine that a guy named Lee Vuong made some parts for 2002, E21, and the E30 M3 including high end racing brake kits and some small stuff for Megasquirt.  I was told to look up a place called Massive Brakes.  After a few searches on the web and some searching in www.s14.net, I located www.massivebrakes.com and a thread on s14.net for an EDIS trigger wheel and sensor bracket kit for the S14 engine.

Lee is offering a 36-1 trigger wheel and sensor bracket.  The trigger wheel is sized to be a shrink fit over the crank pulley.  Heat the trigger wheel up in a 450 degree oven and then drop it over the crank pulley.  The sensor bracket is mounted to the two lower water pump mounting bolts. Here are some pictures that I copied from Lee's thread on s14.net.  These are his pictures and not mine.  They show his kit, a drawing of the sensor alignment, and some installation pictures.

I ordered the S14 trigger wheel kit from Lee at Massive Brakes and it arrived a week later like promised.  The kit contains the trigger wheel, sensor bracket with sensor mounting hardware and two longer water pump mounting bolts.  I cannot shrink the wheel onto my pulley until I can establish the wheel's position.

	I test fit the VR sensor and crankshaft pulley and measured where the trigger wheel needed to be located to be in line with the center of the VR sensor.  On my engine this ended up with the trigger wheel just over 0.5 inches from the inside face of the pulley.
	Installing the wheel.  I marked the tooth that needed to be aligned with the TDC mark.  I used some 0.5 inch aluminum for spacers.  I baked the wheel at 450 until done (about 30 minutes) and then dropped the heated wheel on the pulley.
	Pictured of the wheel and pulley installed in a test fit.  It is a little bit off (about .025 inches).  A flat washer in the sensor mount will correct this.