370z GTM Stage 2 twin turbo Stock block

Originally Posted by Speedy

I must be dense. What video?

Originally Posted by SAM@GTM

....

UNDERDRIVE PULLEY is a bad idea all the way around for few reasons :

- Despite what anyone says about this engine being internally balance and removing the harmonic balancer does not have any effect on this engine is totally false. So by removing the harmonic balancer (witch is made from two part metal and rubber in the middle bonding them together for the sole purpose of absorbing engine harmonics and vibrations ) you are destroying your engine .

- Further more by installing the lighter aluminum pulley, keep in mind that aluminum is softer then harden steel (crankshaft) you are also taking a chance of either killing your crankshaft or being unable to ever remove the underdrive pulley since with time it will weld it self to the crank. and here is exactly what happened in this case, So we had to remove the whole front end, radiator support, a/c condenser so we can put a big enough air gun to brake loos the bolt and still had hell of time to do so .

Also I'm quoting the same info from the web