m20 harmonic balancer

[hasa]

Old topic... but still valid.

I've been thinking if one could use the low timing belt gear from E21 323i ( 11211264531 ) and M50 harmonic balancer (VAC, Ross, MRT younameit... basically ATI adapter) together.

[redneckvtek]

Would love to find a solution. My OE m20 unit is starting to show signs of degredation of the rubber bonding the pieces which Im sure will eventually affect timing/function.

[digger]

I have a m20 specific solution with minimal mods but would need to get 10 made with 6-9 month lead and they would not exactly be cheap with sleepy joe inflation, Covid tax, bmw tax, Putin tax, et al

[ForcedFirebird]

I have a m20 specific solution with minimal mods but would need to get 10 made with 6-9 month lead and they would not exactly be cheap with sleepy joe inflation, Covid tax, bmw tax, Putin tax, et al

What kind of quote did you get per unit?

[digger]

What kind of quote did you get per unit?

about ~$1000

[zaq123]

about ~$1000

any details on the unit? is it similar to OEM or solid material just for a sake of toothed wheel?

[digger]

It is an ATI super damper so it uses a standard inertia ring (7") with rubber o-rings (tuneable based on the rubber duro) that is rebuildable. it has the factory pulleys for the WP+Alt, PS and A/C. includes the same 60-2 trigger wheel which is part of the solid shell unlike the factory peice where the trigger wheel is resiliently mounted

[redneckvtek]

It is an ATI super damper so it uses a standard inertia ring (7") with rubber o-rings (tuneable based on the rubber duro) that is rebuildable. it has the factory pulleys for the WP+Alt, PS and A/C. includes the same 60-2 trigger wheel which is part of the solid shell unlike the factory peice where the trigger wheel is resiliently mounted

If all 3 parts are bolted to the lower timing gear, what provides the damping? I thought the rubber flexing between two masses was the method of energy absorbtion?

[digger]

If all 3 parts are bolted to the lower timing gear, what provides the damping? I thought the rubber flexing between two masses was the method of energy absorbtion?

the blue inertia ring is held in place by rubber only.
the grooves in it are for large o-rings 6 off. These are not shown

[Everson]

I’m interested

[redneckvtek]

the blue inertia ring is held in place by rubber only.
the grooves in it are for large o-rings 6 off. These are not shown

Got it, I was thinking the blue was the rubber. I like that the inertia ring is captured.

I wish I could be in for this, I want one bad, but I can't use non-OE pulleys in my league.

[zaq123]

Got it, I was thinking the blue was the rubber. I like that the inertia ring is captured.

I wish I could be in for this, I want one bad, but I can't use non-OE pulleys in my league.

Digger would know better but I don't see why they would design it with new non OEM pulley? Bolt circle doesn't change .....unless it was impossible to maintain the same thickness at the crank bolt area of this damper.

[digger]

Digger would know better but I don't see why they would design it with new non OEM pulley? Bolt circle doesn't change .....unless it was impossible to maintain the same thickness at the crank bolt area of this damper.

its not possible to use the OEM sheet metal pulley. The flanges on the outer and inner shell are thicker and it’s not possible to make them thin enough. The factory vibration damper is single ply like 3-4mm thick whereas the damper requires two parts sandwiched together with a high level of stiffness

[moatilliatta]

Got it, I was thinking the blue was the rubber. I like that the inertia ring is captured.

I wish I could be in for this, I want one bad, but I can't use non-OE pulleys in my league.

Can you find a pully from another BMW?

[hasa]

Now I have seen two examples for M20, one from Belgian tuner Atrex and this (probably the same)

https://www.schaper-automotive.com/en/detail/238d32e4db024a90a893e5f1d2c3bd6b