Thread: Pulleys and Flywheel

Since I decided to go with an Avenir, I am not having a hard time deciding if it is worth putting on a Fidanza Flywheel and UR Pulleys 2 set.

I've heard plenty of stories where flywheel would be a bit problematic on a boosted car, as in no traction and revving too quickly.

Now thats on Fidanza 8.8 lbs flywheels, from what it seems like the B14 safe, 108 tooth flywheel, is around 10lbs because it uses the stock ring. I haven't been able to confirm this yet (still waiting for it to arrive).

Now as for Pulleys, I wasn't worried about the UR pulleys causing any problems until I heard about the ATI Damper pulleys and this page (where they basically say it is dangerous to use Underdriving pulleys).

I would like to have the Fidanza and the UR Pulleys on for the added power and MPG improvements hehe.

Thoughts? Discuss

I would sell that stuff and invest the money in a wideband

that article about aftermarket pulleys sounds like scare tactics to get beemer owners to only buy their aftermarket pulleys.

there was a thread about the pulleys a while ago. alot of guys have been running UR pulleys for years with out problems. I think there was something in the mazwork drag car build about it aswell. think you only need it if you making HUge amouts of power that you have to use the dampener

Haha that would be nice.... maybe someday...



Agreed, it did seem like more of a scare tactic... Maybe BMW's are more prone to that issue?



Sweet, keeping the pulleys then

Both are great to have! But both are not necessary also. If you don't already have them, spend the money on the turbo goodies.

B

Great! Well I already spent the money on both for my NA build that turned into a snail build

^Yes. Years. You going to let that one article scare you Vadim? This is the SR20 motor we are talking about. Not the E36. I'm putting a 4 piece and a 8.8 pound on both my projects.

Just don't underdrive accesories. Like P/S and altenator.

Get the crank and waterpump pullie and your set.

It may be a scare tactic, but it is true. The amount you may be affected by this truth is up for debate. Your engine life will be lessened, but by how much is up for debate. Those running pulleys without harmonic dampeners for years will say there's little to worry about and may have the final word on this, but to say the phenomenon doesn't exist is wrong. To be fair, the longer crankshaft of these BMW engines are more prone to harmonic damage, making these claims ring more true for those engines than ours.


I remember it. I actually argued against the need for it in that thread. This was before I completely understood what I was talking about, and have since changed my stance.

This is maybe the most important factor in all of this.

It's not so much the power you have to worry about, but the revs.


If you want my advice, I'd keep the factory crank pulley and save the money for other things. I'd certainly do the flywheel though. If you've already spent the money, then I guess you might as well toss them on.