I understand money is money but I suggest you use the recommended octane fuel in the car. You bought a high performance Corvette....treat it right. 
Octane?
Racer
Joined: Apr 2012
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From my manual (2005):
Gasoline Octane
Use premium unleaded gasoline with a posted octane of 91 or higher for best performance. You may also use middle grade or regular unleaded gasoline rated at 87
octane or higher, but your vehicle’s acceleration may be slightly reduced. If the octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs,
use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine.
I've been using 87 for almost a year now. I have great acceleration as it is lol
Gasoline Octane
Use premium unleaded gasoline with a posted octane of 91 or higher for best performance. You may also use middle grade or regular unleaded gasoline rated at 87
octane or higher, but your vehicle’s acceleration may be slightly reduced. If the octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs,
use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine.
I've been using 87 for almost a year now. I have great acceleration as it is lol
Melting Slicks
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From: NJ
Team Owner
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St. Jude Donor '13
...
It's best to use 91 or 93 depending on what's available for best performance and to keep the ECM from constantly having to pull timing to protect. However, the car WILL adjust to 85 or 87 but you'll probably see timing being pulled even at less than WOT. Also you'll be relying solely on the knock sensors to protect your pistons from getting holes burned in them.
That is mostly sea level to probably 4,500ft advice. At higher elevations you can get away with lower octane due to the density altitude and oxygen levels or something. Its why you'll find 85 octane in places like Colorado.
It's best to use 91 or 93 depending on what's available for best performance and to keep the ECM from constantly having to pull timing to protect. However, the car WILL adjust to 85 or 87 but you'll probably see timing being pulled even at less than WOT. Also you'll be relying solely on the knock sensors to protect your pistons from getting holes burned in them.
That is mostly sea level to probably 4,500ft advice. At higher elevations you can get away with lower octane due to the density altitude and oxygen levels or something. Its why you'll find 85 octane in places like Colorado.
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From: Guelph, Ontario
I run 94 in mine, but there are times when I go on road trips and all that is available is 91 so I use that. It could be my imagination, but I feel as if my engine isn't making as much low end torque when I'm running 91 on hot days, so I wonder if my car is running in a low octane table under those conditions?
Advanced
Joined: Jun 2012
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From: Port St. Lucie FL
Some of you are suggesting that I'm mistreating my '12 base coupe by feeding it 87 octane gas when I go on long distance highway trips. Around town I use 93 octane for lots of stop and go, and spirited acceleration. The long haul steady 75 mph cruising does not create any knocking and produces excellent fuel mileage. My owners manual says, "You can also use regular unleaded gasoline rated at 87 octane or higher, but the vehicle's acceleration could be slightly reduced, and a slight audible knocking noise, commonly referred to as spark knock may be heard." As far as burning a hole in a piston, that happens while running extremely lean fuel mixtures, not 87 octane gasoline. Huge difference. Many high performance engines run fine on the recommended 87 octane gas. My YAMAHA FJR1300 is a perfect example of a high compression engine that did 0-60 in 2.8 seconds on 87. I know, apples and oranges! YMMV
Respectfully,
Bob
Respectfully,
Bob
Drifting
Joined: Jan 2005
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From: Houston Tx
Some of you are suggesting that I'm mistreating my '12 base coupe by feeding it 87 octane gas when I go on long distance highway trips. Around town I use 93 octane for lots of stop and go, and spirited acceleration. The long haul steady 75 mph cruising does not create any knocking and produces excellent fuel mileage. My owners manual says, "You can also use regular unleaded gasoline rated at 87 octane or higher, but the vehicle's acceleration could be slightly reduced, and a slight audible knocking noise, commonly referred to as spark knock may be heard." As far as burning a hole in a piston, that happens while running extremely lean fuel mixtures, not 87 octane gasoline. Huge difference. Many high performance engines run fine on the recommended 87 octane gas. My YAMAHA FJR1300 is a perfect example of a high compression engine that did 0-60 in 2.8 seconds on 87. I know, apples and oranges! YMMV
Respectfully,
Bob
Respectfully,
Bob
Le Mans Master
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From: corpus christi Texas
Sounds stupid probably, but besides what ever GM first put in, my car has only ever seen Chevron 91. Daily driver too. I didn't even let the dealer fill the tank when I bought it because I didn't want some lot boy rowing gears and putting budget station 87 in.
The things we do for our cars......
The things we do for our cars......
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St. Jude Donor '13
I would agree that your risk of knock-related engine damage is very low while cruising an interstate highway. I’d get a bit more heartburn if on a 2 lane road where you might want bursts of acceleration to pass. But as long as you don’t have a Z06, ZR1, or modded engine that need at least 89, and as long as you pay attention about any heavy knocking which might indicate a problem with your knock sensor or a bad batch of gas, you should be fine. I guess what people might be reacting to is that the savings don’t seem all that dramatic. For a 1000 mile trip, you’d use around 35 gallons, and if premium to regular price difference is 30 cents, that’s about 10 bucks. Most people seem to think it would be worth 10 bucks so you can punch the throttle here and there without having engine knock in the back of your mind. But 10 bucks are 10 bucks, and if it’s worth it to you, go for it.
Melting Slicks
Joined: Jul 2011
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From: NJ
correct, I dunno bout all you guys but I didn't buy my car for MPG amount... If that was the case I would of bout a 4 banger Honda civic lol