Well, i think the E-test does give you an afr at 2000RPM or something but you're looking for consistancy during the RPM range. Get a dyno done. Dont worry about the chip, your car has knock sensors, it will retard the timing if need be.
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Hot: 2001 Estoril M RoadsterZCP 19's michelin supersports, ZHP knob, JL 8W3
Cold: 2002 TiAg M3 6mt
ZCP 19's michelin supersports, deoranged, dechromed, led tails, ZHP knob, UUC SS v3, GROM, OEM 18's w310's,
Fun: 2006 YZF-R6, black, ohlins, pazzo, graves