fastdoc71

Can a C6 with all the necessary E85 components (flex fuel sensor, upgraded injectors and fuel pump) that has already been tuned for E85 safely run VP C85 for the purposes of the dyno or track without any tuning adjustments?

KM177122

I would say yes so long as you aren't running super aggressive timing. If you have a conservative tune and your flex fuel sensor is functioning then you should be good. But I would run it past a more knowledgable tuner before trying it.