Just got my new like new '99. Can you run mid grade or regular if your not mashing it hard?

 

Yes, but why do that? Premium is under $2.50/gallon. What will happen if you buy lower octane fuel is that the ECU will retard timing and you will lose a chunk of horsepower. And if for some reason your knock sensors are bad, you could destroy your engine. Now if you commute 100 miles every day in slow traffic, consider getting a daily driver and save the C5 for Fridays and weekends.

As you can see, my opinion is this: If you own a Corvette, don't use Winston tires, Monroe shocks, or regular gas- it just aint right!

 

You know Dave I totally agree....don't complain about the insurance,gas,tires....you can almost beat anyone on track day, if not everyone, then get 28 mpg on the way home, for 4 bucks more a fill up get the good stuff...just my opinion

 

I agree it is nonsensical to routinely use regular in a 'vette. In an emergency (you're low on fuel and the station has no premium) it surely won't hurt. However, if I were going to run regular all the time, I would have the engine tuned for that, by having it dynoed tuned while running regular. You'd lose a chunk of power, but calibrate the ECU to do the best possible, and not to depend completely on the knock sensors.