Do C5 Corvettes require Premium (or can you use 87 & 89?)

C5 Corvettes run best on premium fuel (or 91 Octane or better) but can you run 87 octane if you want? What about 89 Octane fuel in a C5 Corvette? Let's cut through the myths and guesses and go with some qualified sources and some opinions based upon facts.

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[markmartin]

I've used 87 in mine, and it runs fine for granny driving but it will ping and knock if you drive aggressively. Put 91 in and it's good

[alaneasterday]

My area has 87-89 and 93. I normally use 93, but have used 87 in the past with no issues. Appreciate all the helpful content!👍👌

[theiceman]

It’s a special day today.
I just purchased a black 2004 Corvette Z06
My first corvette!
Thanks for all the excellent videos,
keep the C5 Alive!

[anthonyezell]

I've ALWAYS put 93 octane in my C5 Corvette!!!!

[samhoff]

As someone who is interested in saving up for a C5 corvette, this video was incredibly helpful in factoring costs for what I may need. Thankyou for this information.

[christopherdutro]

It just never FAILS! Show after Show are Top quality topics done in a professional way. BY FAR the best C-5 you tube channel! "Way to go Man" ( an old 1970s term) for what it's worth I have had to use 89 octane twice in the 8 years I have owned my "99" I am still being true to the Last nice car I will ever own ! Thanks again for the great shows! Question how long have you been Broadcasting?

[floodx]

Nothing more fun than reading the comments on Corvette social media. :-) I have owned my '04 since new, and have enjoyed all of the 139, 910 miles currently on the clock. The choice of what fuel just requires using your brain a little. Spring and fall, I run 87. Hot summer months, I run 91. I do my best to avoid ethanol, but I only "actively" avoid it on the last couple tanks before winter storage. And even during that time, it's probably not a huge issue, as I often will get a chance at least once a month to go for drive in the winter.

[ztzqufz]

The other day I was getting gas in 2000 c5 and I noticed that a guy was getting gas in his 2015 and he was putting in 85 and told him YOU CAN'T DO THAT! He chuckled
A few days later, he was in the dealership with a blown motor, I chuckled 🤭
Great video

[scotthayesproductions]

I usually run 93 in mine, but on long roadtrips, 87 might be just fine at a constant speed.

[ejsoder]

Been driving a 1999 C5 as a daily driver using only the cheapest gas I can get. Have put 100, 000 miles on it since my ownership and bought it when it had 50, 000. Yes, the car has 150, 000 miles on it now and still am driving it as a daily driver and have experienced very few maintenance issues that I have not been able to take care of myself. Heck, I have never even done a break job yet (It's getting about time though) and did not bother to change the plugs until they had 112, 000 miles on them. These cars are great GM products. Go run them as much as possible and enjoy. Heck, I only paid $18, 000 for it 17 years ago and its still worth a solid 10 or 12! Good informational vid.

[jeidm]

I have been looking for this question everywhere! Thank you for posting it!

[chrisambrose]

I run 87 in mine all the time. I don’t race it, just drive it. Once in a while I’ll treat to 93, but not very often. It’s a 2000 roadster with 133000. On it and she runs great. 28 mpg over all on long trips.🙋‍♂️🖖🏻

[leonlawrencez]

I have never seen 91oct in my area. All we have is 87, 89, 93. I try to only use Shell 93oct. I use one bottle of techron three times a year. Runs great. No knock. No exhaust smoke/ carbon under heavy acceleration. Exhaust tips stay clean. Only time I have seen 91oct is at a Sunoco across the street from Daytona International speedway.

[thehomer]

Yet another great video. Really like your content. I've had my '03 coupe now for about 5 months and have religiously put 91 ethanol-free gas in it. I'm in Montana. 91 is the highest octane rating anywhere I've been in the state, and it's the only grade offered ethanol-free. I really appreciate the break down into 3 groups. I'm definitely group 2. I'm going to try mid grade with ethanol for a while just to see if there's a difference. I'll run the last few tanks before winter storage with ethanol-free 91 to clear the lines of anything that might cause condensation. Thanks for sticking your neck out and for a fresh perspective on this issue! UPDATE: I've run a tank of mid grade with ethanol and have had NO issues. No knocking or hesitation, and acceleration sounds and feels the same. What a relief! Not just in terms of cost, but also convenience. Not many stations have ethanol free fuel. I'll be using this formula most of the time, and switching to premium ethanol-free before storing for winter. Thanks again for this video and keep the content coming, damn the risk!

[johndavidwolf]

The minimum octane requirement for normally aspirated (not turbo or supercharged) gasoline engines generally decreases by one point for every 2500 ft (750 meters) of elevation above sea level, so 85 octane "regular' is sold at higher elevations like around "the mile high city" of Denver CO and other places of that elevation.

[straightcut]

No grief here on your good video, but I would add higher octane is better for high elevations, hilly areas and very high ambient temperatures. I’m in Phoenix, AZ - when the temps are over 100F and under load, I’ve noticed a propensity to ping.
Keep up the great videos!

[Ksbigdad]

Best C5 YT channel out there!!! Thx!!!

[GregSr]

I have a 2003 C5. I usually run 91. In a few cases, I've used 89. I can't tell any difference. I don't use 87. I rarely hammer the throttle but I do enjoy an on-ramp blast now and then.

[nowayjose]

I was wondering if you were going to mention the two different spark tables for high octane vs low octane fuel, and then bam, there it was. Great information as always. It's definitely appreciated.

[octoman_games]

I have a 91 octane tune on my C5. Mild cams and AFR heads required it.