i have a 03 g35 sedan. 350Z Z tube with pop charger, test pipes and coupe mid pipe... i was looking at stock size lighten pulleys. Crank, alternator, and idler pulley. i was wondering if anyone has done this or would recommend it for some more HP. Ralco RZ Pulleys

 

I would recommend getting a Motordyne plenum spacer at this point. That will give you proven gains. You likely won't notice much of a different from the pulleys.

 

yeah i was debating on that or pulleys thanks for the input!

 

a lightweight crank pulley is a good mod, but not nearly as good as the MD spacer, as Marcus said

 

+1 on a MD spacer. if you go with a LW pulley, go stillen or UR. i have stillen.

 

Motordyne hands down... I made between intake and spacer 10+whp that was astonishing to me.

 

From what i heard, you should leave your crank pulley stock no matter what. because it has some sort of ring on it, keeping vibration down and any oem pulley does not have that, and can hurt your crank, in the long run. Do you anything about that?

 

I have 192k on the odometer.... ZERO ISSUES!

 

Also known as harmonic balancing, some believe aftermarket pulleys unbalance the engine. The ring supposedly acts as a seal to prevent the leaking of oil.

I had the UR underdrive pulleys on for a while and didn't have any issues. I also did a before and after dyno and the pulleys did nothing performance wise.

 

Yup I've heard the same thing from a few friends. Haven't looked too much into though since I wouldn't replace my crank pulley unless I went FI. If I did get one it would be one that has a harmonic balancer.

 

There is a special feature dyno's have... A lot of people are not aware. But it's called engine speed vs time.

It can tell you how fast it took to make that power, so if the power is consistent but the time it took to make the power was quicker then it's a sign of improvement.

 

True, but I highly doubt a person would be able to notice the difference, I certainly didn't. IMO, reducing the weight of the pulleys alone on a DD probably isn't worth the cost. Maybe on an all out track car that has a light weight flywheel, driveshaft, wheels.....etc, then they might be worth it but I don't have any experience with that so .