Paul from Pennsylvania stopped by for spark plugs and intercooler fill/bleed kit. Once his car was running smoothly it made 428 whp and 436 wtq, which was on the high end of stock ATS-Vs. Next we added our custom dyno tune, dialing in the WOT boost, fueling and ignition timing. Peak power increased to 473 whp and 494 wtq, with gains of more than 50 whp in several parts of the powerband. Pretty impressive for his 91-octane fuel!