Which ATI Part # did you get? I accidentally ordered the undersized pulley (918584), and now I'm trying to find out the part number for the stock size wet sump application pulley. I have reached out to MA Motorsports regarding this.
To replace the stock belt, I purchased Gates Racing Serpentine Belt Part #K070795RPM.
__________________
2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |