I purchased a JDM ITR crank pulley with 3 ribs for Alt, PS, AC but they are smaller diameter than my USDM GSR crank pulley. So my belts are way too big. Are all ITR crank pulleys smaller diameter or is it because its JDM? And what size belts do I need to get?

 

This kind of things sort of surpised me too. I swap out a gsr crank pulley for an ls pulley and the a/c beltl needed resizing. You would think and like that they are all the same but who knows . I suggest you bring the old belt to an autopart store and ask them to find a belt that have the same groove and desired length. This is what I did...I think I ended up using a dsm alternater belt.

 

I also bought an itr crank pulley because it's slightly lighter than the gsr and you could still use your AC and powersteering, unlike the ctr n1 pulley. I did some research when I bought it so this is what you need if you want to run the itr crank pulley on the GSR:

-ITR Alternator Belt
-ITR AC Belt
-GSR Powersteering Belt

 

Thanks guys.

 

what is the benefit of this upgrade?

 

its lighter, and slightly under drives the accessories. /thread