I have a 99 Corvette with a Diablo tune U7198 9r latest revision. Car runs great no issues , Should I take off the tune and return it to stock before having it tested for smog or leave it alone.
Only thing I have changed is the air cleaner put on a halltech.
Diablo Tune and California Smog test
RE: Diablo Tune and California Smog test
you can leave it alone... probably runs more efficient with the tune on there compared to stock anyway 
06MonteSS / DiabLew Tune
2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com -- www.diablocustomtuning.net
2014 Camaro SS - 2SS, RS pkg., short-throw shifter, NPP perf. exhaust, BMR strut-tower brace, Cold Air Inductions cold air intake
www.diablewtune.com -- www.diablocustomtune.com -- www.diablocustomtunegm.com -- www.diablocustomtuning.net