If that's all he did, that must be one hell of a tune to knock a second off the 1/4 mile. Those are high 13's stock, which is still impressive for such a BIG car.
You should take it with your mods, but it will be close since it's AWD, so you'll have to have a good start.
None of this --->
Oh and nice choice of colors..
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2010 1SS RS, LS3, SIM/Black, painted rally stripes, AAC sidemarkers, Sunroof, B.A. sound sys; 20x9.5 & 20x11 SV1-C5's; MGW short shifter; Hotchkis Track Pack; Corsa catback; Kooks 1 7/8"; ADM Street; Magnacharger TVS2300 - 548rwhp/512rwtq
1100- 2/18/09; 3800- 6/15/09 VIN#18308; Delivered 6/29/09!!!!!
2014 CTS-V Sedan, Black/Black, Auto, Recaros, Ultra-view, Red Brembos. Stock