What would be the best option for a Z06? Limited choices in my area.

Shell, top tier, 91 octane with no ethanol.

Off brand, not top tier, 93 octane with 10% ethanol.

Off brand, not top tier, 93 octane with 10% ethanol with frequent Chevron Techron Fuel System Cleaner.

 

Tough call. I try my best to avoid non top tier gas, but I believe it is known that the motors in C7s have optimum performance with 93 octane.

 

My choice would be - Shell, top tier, 91 octane with no ethanol

 

I would go for the non-ethanol 91, but all are safe for this car. I just prefer my corn liquor in a jar and not the engine.

 

+1.

 

IMO Top Tier 91 without ethanol is better than getting two octane points without the Top Tier standards
The computer adjusts ignition timing to avoid detonation so the only "downside" is a very small decrease in maximum HP ... I reckon most of us couldn't tell the difference in performance between using 91 and 93 octane..

 

93 Octane top tier or not works for me.

 

I would choose the Shell gas.

 

I do shell gas and put in 3-4 gallon of 100 octane here in Cali.

I have a place close by that has it. Its about 8-9 bucks a gallon which sucks but its not like I daily drive it. I dont trust the orange additives.

 

Anybody familiar with the chevron 94 octane with no ethanol? How does that compare with the shell 91 octane with no ethanol? From what I have gathered from other people's opinion, they think the shell is the better choice.

 

Any of the 3 choices would work as these cars are designed to work with 10% ethanol, I would choose the 93 octane non top tier with Chevron Techron option

 

any 3 of those choices will work just fine, the computer will deal with it...

 

Depends. Is the ECU tuned to exclusively use 93? If not, then use the highest octane, best quality, gas you can reasonably find. It won't hurt anything to toss a bottle of techron in every couple of tanks. (but in a DI engine, it doesn't do anything in the motor, and it's not an octane booster.)
If you really need to boost octane, add toluene.

If this is just a relatively stock driver. just put gas in it.

 

I just posted a similar question about a week ago and got ton on opinions. It is on page 5 now if your interested. Called TopTier fuel question. I don't like to put alcohol in my car. But all the TopTier fuel I have found in Missouri has alcohol. Caseys Convenience Stores which is big here in the Midwest sells premium without alcohol at some of their pumps, but it is not TopTier. That's what I have been using in all my stuff. Harley, mowers, Corvette, Kia.Soul. Just don't like to use alcohol. Especially in a vehicle that sets a lot.Everyone know alcohol draws moisture. Just my opinion.

 

Top tier with highest octane. The 10% alcohol won't matter. Do as the Manual says and use an appropriate additive... I use the GM product, but twice as often. I've run such in ALL my performance vehicles in a similar fashion for years without issue. All the best.

 

We have at least three things going on, here; octane vs. top tier vs. ethanol.

All should be taken separately.

Ethanol is not an issue according to the OM. Sure, it's nice to have ethanol-free gas, but many places it is just not available. Don't sweat it. Our engines are designed to handle it.

Octane should be taken seriously, get the highest level you can, but the car can run on regular. Beware, though; even though the car can run on regular, you should only do this temporarily, until you can fill up with either 91 or 93, or engine damage may occur. The car will retard timing (to eliminate knock), thus reducing performance, It's a dangerous dance, though; press it hard, retard timing, press, retard, press, retard. Not good to even get it to the pre-knock stage where the car detects it.

Top Tier. This for the most part means higher detergent, even though there are high detergent gas brands that don't pay the licensing fee. The problem is which brands (local station) that aren't part of the Top Tier group have the added detergent above federal standards? Even if you use Top Tier exclusively, I would recommend adding a bottle of Techron every oil change, anyway. My '14 got Top Tier exclusively, and still developed the dreaded dead fuel level sensor, which is where the fuel level sensor/sender developing sulfur on the silver contacts. Strictly a detergent issue since we bought a car with silver contacts in the gas tank. It is not a cheap fix (anywhere from $2000-4000.

 

Is the shell V power 91 octane with no ethanol comparable to what chevron has with their techron?

 

None ethanol 91, been doing that for years with 3 of my Vettes one was a Z06 FWIW I would not use ethanol crap in my lawn mower, let alone a good car.

 

Agree 100% I am fortunate enough to live in an area where ethanol free gas is easily found and priced like its ethanol added counterparts. When I used to live in Texas, ethanol free gas was easy to find, especially if you drove by a Buc-ee’s every day during your daily commute.

The Buc-ee’s I went to had over 100 pumps, 10 of them were all ethanol free grades of gas.