Jon over at MA Motorsports said exactly what we seem to have concluded in this thread: there is no exactly stock size ATI pulley.
The ATI damper for wet sump application is a 4% underdrive pulley. He confirmed that the stock belt size should work. They reused the stock belt for Spooler's build with the ATI damper.
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2011 370Z 6MT Sport Gun Metallic | ARC | CJM | Ecutek | FI | Fujimura | R2C | SPL | Stillen | TWM | Z1 | ZSpeed | |