Is there any benefit to using an aftermarket lightened alum crank pulley or stick with the heavy steel stock crank pulley on a vq35de with rods and pistons with single turbo for 400-500 hp range??

 

neither, go with a harmonic damper pulley.

 

+1 ATI or Fluid Damper

 

I got fluidampr, so far so good...

 

I am using the UR lightened crank pulley, with the Greddy TT kit for 3 years. No problem here

 

The conventional wisdom is that lightweight pullies and F/I are a no go.

I ran a brand new Fluidampner pulley on my high HP builds (2 motors) and both ate main bearings within 1000 miles. I am now back on the stock pulley and will send the Fluidampner out to AAM to be rotational balance tested on a crank up to 8K rpm before re-installing on the car.

If the pulley is bad it should have caused a noticable vibration, but at this point I will error on the side of caution every time.

 

If my choice was between stock, and a lightened pulley, I would choose stock every time. Although, I have heard good things about the ATI pulley.

 

I had the UR pulley from NA that I left on when I did the TT but when I went to the built block I used the stock one, it is light enough that I didn't see the need for a light one

 

....I am a living example of what will happen if you use a lightweight pulley on an FI'ed car...I had to change my crank. Stay away from that stuff when you have an FI car.

 

^ 1 Stick with stock. Spend your money on something else that benefits FI.

 

times that by 2 ->

I have the bad crank sitting under my workbench to prove the damage they can do.

I am running an ATI superdamper on my current setup

 

It was your warning I first saw....soon after...Sharif found the problem

 

ATI here.

 

Wow, had similiar interest in installing Light weight pulley's, glad I held out on doing so. Thanks for the insight guys.