The Unorthodox Racing under drive pulley can make any change in my car performance. In the SportCompactCar of February 2001, in the section of project Nissan 200SX, they have an article with information of this pulley. They that many of the inline four cylinder engines don't need an harmonic balancer as much because they have short, stiff crankshafts. Our tibs engines have this specs or they need a balancer?

 

Noel i have had that pulley for over a year and a half now and need nothing else to install and have no problems whatsoever with the pulley to this date. Hope that helps you.

 

I also have that pulley and I like it too.

 

Did you notice any difference in you car performance.

 

Noel-

There is currently a "debate" in the automotive aftermarket community about the negative effects of Crank Underdrive pullies.

Some say there is no harm, others say they can cause serious harm.

Some have had problems after as few as 10,000 miles, others have had 100,000 trouble free miles.

I suggest you search www.fxtreme.org and www.teamsr.org, and then make you own opinion from what you read.

In my personal opinion. The 3-5 HP gained is not worth the potential damaging effects.

 

To further comment, this is probably the only $200 part that isn't going to be installed on my $5000 motor project. I'd rather live without the paltry 2-5 horsepower gain in favor of a longer crankshaft life.

There are serious issues involved in lightened crank pulleys, the least of which is harmonics, but rather load balance. Lightened flywheels are fine and dandy because the load on the flywheel is directly centered on the axis of rotation -- a lightened crank pulley is dangerous because the load on the pulley is NOT centered on it's axis, but is way off to one side instead.

Search the FXTreme forums for mention of pulleys, and you'll find the long and drawn out conversations about this.

Again, that is $200 that you will never find on my motor.

-Red-

[ September 13, 2001: Message edited by: Red ]