So i have been reading up on lighten crank pulleys, and how they are bad for the engine bearings. Reason's people say they mess up a bottom end, is because they are not blanced and basicly destroy engine bearing setting the motor off set. Would this be a factor as well for using a ligthen clutch

 

It's not that they are light,its that they no longer incorporate a harmonic damping device.Lightweight flywheels and properly designed crank pulleys are no problem to use.

 

yeh, i highly recommend the fluiddamnpr

 

i highly recommend the ATI superdampner. it is tested to be better at high rpms where as the fluid damper starts losing its effectiveness over 7k rpm

 

It is not that they are unbalanced it is that the the oem crank pulley is dampened to obsorb the crankshfts vibrations made from the downward thrust of the piston and connecting rod. I would not buy an aftermarket crankpulley unless it was dampened. If you look closely at the oem one you will see almost like a rubber bushing inside.

 

aftermarket crankpully doesnt have the damper like the OEM so your bottom end will have premature wear later down the road..if you want a OEM pully that is alittle lighter, i think passwordjdm has a ITR pully that has been lightened and still has the damper on it

 

well i was thinking of getting the stock crank pulley machined down to have the only the alternator section on it...

 

I have had the full U/R pulley kit on my boosted D16Y8 for
200 000kms, 150 000kms boosted. My car currently has
280 000 kms. Unless you are driving at the track with your tach. pegged on the red line all day I wouldn't worry about it.

 

I have heard alot of debate on this subject and my take on it is to look at what you have on the car. Some of the pullies I have seen have the damper some do not. If yours does not I would say that a lightweight pulley will be fine however, If it does have the damper stick with what you have or buy a damper equipped aftermarket. To tell If yours has a damper or not first you hay have to take it off. Once it is off look on the back side for a circle of rubber. If you have no rubber it is not dampened if the rubber is there it is dampened. Hope this helps

 

IDK, all i know is i switched to a CTR pulley, then shattered an oil pump. bought an ATI, revved higher, no problems

 

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i'd invest in a real performance pulley. We've done those back in the 90s, and they were balanced as well, but looking back, I wouldnt do it again. We just didnt have a choice back then. There are high quality pulleys available out now just like the ATI that are worth the money,.

 

I really don't buy into this hype. I've been running the CTR N1 pulley for a good 50,000 brutally hard miles on my b18c5 and not a problem. I've torn into the engine a few times and my bearing tolerances are still in great shape. And I really need to stress the beating I do to this engine (including the time when I handed the keys to an ex-friend and he over revved the engine to 12.5K bending every valve). I've blown up so many pressure plates and clutch discs which threw the bottom end assembly way out of balance as well, and still no ill effect. And I can tell you that stock pulley didn't stop any of that vibration at all. And lets not forget the D series doesn't have a rubber do-dad in the pulley, and those things go forever (I can think of 2 in the 1/4 million mile range on the stock block, never rebuilt). But hey, this is just me, I loved my N1 pulley (now looking for a 2 groove one because I added A/C). I got a noticeable increase in the climb of my RPM and my quarter times showed increase. But then again, I build my own engine so I'm not so worried about damage and wear.