Hey guys just got these in and i have to say im impressed with the them. They are new AMS lightweight pulley's they are all aluminum with a steel collar on the crank pully to keep the oil seal from leaking around the pulley like some of the other aftermarket pulley's. Total weight on these 2.5 lbs as opposed to the stock 7.6 lbs. Possible gains of 11 hp and 6 ftlb of torque through most of the power band. No underdive to have to deal with so your alternator and your water pump spin at the right speed. check them out
http://www.z1motorsports.com/350_g35...oducts_id=2648. $295.00 plus shipping. Thanks for looking.

 

I have always been interested in a pulley set that is non underdriven. My only worries is that the harmonic dampening of the stock pulley will no longer be present thus causing crank issues down the road. Are my worries valid with this set?

 

The stock crank pulley is not harmonically balanced. Its a cast iron piece with a rubber seal. Only the fluidampr and ati are dampened.

 

I havent experenced any problem like that but as he said the stock one is not balanced so i would not worry. Biggest advantage is the steel collar around the crank pulley, the kjr pulley is **** to leaking out of the front main seal because its all aluminum and the seal wares a groove in the pulley its self.

 

True, but they are dampened to an extent to assist with crank vibrations. I have just heard of a few horror stories of lightweight pulleys ruining cranks and I don't have that money to really take the risk. I'll probably just stick with my stock crank pulley.

 

A properly installed, high quality crank pulley (with a steel sleeve insert) will not cause problems with your crank, or bearings. It's a well worn myth on the boards.

Now, if improperly installed, or no steel insert, then it will fail with enough time.

 

Do the hp/torque gains from these come at higher RPMs or down low as well?

 

Why do I think I remember something about some of the aluminum pulleys having issues with the key way wearing and screwing things up that way? What is this issue with the main seal?

 

On cheaper aluminum pulleys the main seal rubs a groove in the main seal and causes it to leak. The steel sleeve keeps that from happening.

 

I haven't personally dynoed these but AMS has and they said they have seen gains throughout the powerband.

 

Will these pulleys fit a HR engine?

 

Does this kit come with proper belts?? How well does this work with vortech supercharger?? Does anyone else have this pulley kit installed? if so, have they experianced any issues with it?? Does it come with installation instructions??

 

^
-Kit does not come with belts. (at least mine did not)
-IIRC, they have been running these on (local) TT cars without issue.
-No installation instructions, but it should be pretty straight forward..

A few local members have been running these LWP's all (last) summer without issue.
I am looking forward to installing mine in the coming months..

 

well i installed mine over 44k miles ago and ive had no issues with the kjr pulley, i think it comes down to torquing it down correctly and not over torquing the unit

 

+1

 

no, don't think so. Someone correct me if I'm wrong though.

 

Balancing is not the issue with aftermarket pulleys. The factory is fluid filled to reduce vibration on the crank and thus reduce wear. The fluidampr for example is fluid filled but almost no others are.

The main thing to look for in a light weight pulley is the steel insert, not because of the seal wear so much but because aluminum distorts and then allowing the crank key to move in the pulley keyway and as a result distorting the keyway on the crank resulting in a need for new crank. Bad times.

 

The factory crank is not fluid filled--it only has a rubber seal. Only the Fluidampr is fluid-filled. The ATI is balanced and dampened (w/out fluid). But ur right on the crank seal issue.

 

The factory crank pulley is not gel/fluid filled? Are you certain sir?


Who has a cutoff/band saw etc willing to perform an experiment for us? AKA Lets cut some chit up! w00t!

 

How is it dampened?


InZomniac (Is too lazy to search LOL)