Gasoline
Drifting
Joined: May 2008
Posts: 1,693
Likes: 490
From: Denver, NC
FYI - if the motor is stock you are gaining no performance from the 104 - you might even be sacrificing a little. (unless it's a usa/canada rating difference and it's really the same as a 93 in the states - but I believe the 2 places calculate octane the same)
Last edited by Ed Ramberger; Feb 18, 2018 at 09:25 PM.
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wow, they sell 104 at the pump in bc??... what mods do you have to need the 104?... you're lucky, there would be a lot of happy campers down here if we had that all over the place... the reason ethanol can make a car that is tuned on gas run like crap is because the stoichiometric afr is a lot different... a car that is tuned for ethanol can run great
Drifting
Joined: May 2008
Posts: 1,693
Likes: 490
From: Denver, NC
Administrator
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From: In a parallel universe. Currently own 2014 Stingray Coupe.
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The owner's manual recommends premium gas and that is what I would go with. You'll get the maximum performance from the engine by using premium.
Burning Brakes
Joined: Feb 2013
Posts: 904
Likes: 295
From: Sacramento, California
I usually run 91 on my stock Z here in Cali, but I have experimented with gas from a local track using 1/2 tank 91 with 1/2 tank 96. This should give me 93-94 octane and I've noticed my car runs smoother, idles smoother and pulls a little bit harder with this mix. The problem is 96 octane is about $7.40 gallon and 91 is about $3.30 a gallon, so it can get pretty expensive trying to run that mix all the time.
Steve
Steve
Le Mans Master
Joined: Sep 2014
Posts: 5,278
Likes: 539
From: Kelowna BC
And that should have been 94, sorry.
Last edited by grantv; Feb 18, 2018 at 10:40 PM.
Safety Car
Joined: Jan 2015
Posts: 3,830
Likes: 394
From: Rocky Mountains
The best I can get is tier one with 91 octane. There is supposedly another fuel map for low octane fuel, so like the manual says, you could use 87 or 89 if that's all that's available, maybe way out in the countryside. But the ecu will pull timing and produce less hp. Even with 91 octane, on super hot days, it feels like the engine doesn't pull as hard. I think it's a combination of the high intake temperature and the ecu retarding timing to prevent knock. I would use 93 in the summer if I could find it.
Le Mans Master
Joined: Sep 2014
Posts: 5,278
Likes: 539
From: Kelowna BC
wow, they sell 104 at the pump in bc??... what mods do you have to need the 104?... you're lucky, there would be a lot of happy campers down here if we had that all over the place... the reason ethanol can make a car that is tuned on gas run like crap is because the stoichiometric afr is a lot different... a car that is tuned for ethanol can run great
I don't need the 94, but I did have it tuned to run on 94. Only power adder are intake and headers.
I don't know much about the AFR you referred to, just have read some info on ethanol essentially robbing power and causing issues. I found this mostly on a Caravan forum wondering why it ran rough. Running ethanol free was recommended and it definitely runs better since. The van is supposedly made to run on an ethanol blend. That said... I stored it for basically all last year (with Stabil).
Last edited by grantv; Feb 18, 2018 at 10:35 PM.
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Joined: Oct 2010
Posts: 247
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From: Vancouver Island British Columbia, Canada
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Yes, every Chevron station. IIRC Shell offers 93... DAMN... 94 not 104. WTH Grant!?
I don't need the 94, but I did have it tuned to run on 94. Only power adder are intake and headers.
I don't know much about the AFR you referred to, just have read some info on ethanol essentially robbing power and causing issues. I found this mostly on a Caravan forum wondering why it ran rough. Running ethanol free was recommended and it definitely runs better since. The van is supposedly made to run on an ethanol blend. That said... I stored it for basically all last year (with Stabil).
I don't need the 94, but I did have it tuned to run on 94. Only power adder are intake and headers.
I don't know much about the AFR you referred to, just have read some info on ethanol essentially robbing power and causing issues. I found this mostly on a Caravan forum wondering why it ran rough. Running ethanol free was recommended and it definitely runs better since. The van is supposedly made to run on an ethanol blend. That said... I stored it for basically all last year (with Stabil).
Melting Slicks
Joined: Dec 2000
Posts: 3,280
Likes: 1,097
From: Pittsburgh PA
Le Mans Master
Joined: Sep 2014
Posts: 5,278
Likes: 539
From: Kelowna BC
Just what's in the Chevron fuel. I would think using it 100% of the time (even if obviously in smaller amount) would negate buying it separately.
Banned Scam/Spammer
Joined: Sep 2016
Posts: 4,004
Likes: 3,929
From: Philadelphia PA (Birthplace of the USA, UNESCO World Heritage City)
Just make sure you buy gas from a brand that meets Top Tier specs:
http://www.toptiergas.com/licensedbrands/
https://www.consumerreports.org/car-...h-extra-price/
And yes, I would buy premium as insurance against pinging, detonation etc.
http://www.toptiergas.com/licensedbrands/
https://www.consumerreports.org/car-...h-extra-price/
And yes, I would buy premium as insurance against pinging, detonation etc.
Last edited by ArmchairArchitect; Feb 19, 2018 at 11:43 AM.
Drifting
Joined: Mar 2013
Posts: 1,496
Likes: 353
From: Little Rock Arkansas
To the members that are posting about what it reads in the owner's manual, keep in mind the OP's C5 may not have it. When I bought my C5 the owner's manual wasn't there. It would be a bit presumptuous to assume the OP has the ability to immediately access an owner's manual.
In Re: to the topic I have never ran a fuel grade below premium.
In Re: to the topic I have never ran a fuel grade below premium.
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
Here is a list of Top Tier Gasoline for those folks that would like to know.
76
Aloha
ARCO
Beacon
BP/Amoco Ultimate
BP Regular
BP Silver
Break Time
Cenex
Chevron
CITGO
Conoco
Co-op
Costco Gasoline
CountryMark
CountryMark Plus
Diamond Shamrock
Esso
Express
Exxon
Hele
Holiday
Kwik Star
Kwik Trip
Kwik Trip Express
Mahalo
Marathon
Metro Petro
MFA
Mobil
OAAI
Ohana Fuels
Petro-Canad
Phillips 66
PUMA Energy Caribe
QT
QuikTrip
Road Ranger
Shamrock
Shell
Sinclair
Standard
Sunoco Ultratech
SuperAmerica
SuperFuel
Tempo
Texaco
Tri-Par Qwik Stop
Valero
76
Aloha
ARCO
Beacon
BP/Amoco Ultimate
BP Regular
BP Silver
Break Time
Cenex
Chevron
CITGO
Conoco
Co-op
Costco Gasoline
CountryMark
CountryMark Plus
Diamond Shamrock
Esso
Express
Exxon
Hele
Holiday
Kwik Star
Kwik Trip
Kwik Trip Express
Mahalo
Marathon
Metro Petro
MFA
Mobil
OAAI
Ohana Fuels
Petro-Canad
Phillips 66
PUMA Energy Caribe
QT
QuikTrip
Road Ranger
Shamrock
Shell
Sinclair
Standard
Sunoco Ultratech
SuperAmerica
SuperFuel
Tempo
Texaco
Tri-Par Qwik Stop
Valero
Acct Suspended APR 2026 by request
Joined: Dec 2010
Posts: 10,367
Likes: 1,272
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
Racer
Joined: Mar 2016
Posts: 399
Likes: 31
Here is a list of Top Tier Gasoline for those folks that would like to know.
76
Aloha
ARCO
Beacon
BP/Amoco Ultimate
BP Regular
BP Silver
Break Time
Cenex
Chevron
CITGO
Conoco
Co-op
Costco Gasoline
CountryMark
CountryMark Plus
Diamond Shamrock
Esso
Express
Exxon
Hele
Holiday
Kwik Star
Kwik Trip
Kwik Trip Express
Mahalo
Marathon
Metro Petro
MFA
Mobil
OAAI
Ohana Fuels
Petro-Canad
Phillips 66
PUMA Energy Caribe
QT
QuikTrip
Road Ranger
Shamrock
Shell
Sinclair
Standard
Sunoco Ultratech
SuperAmerica
SuperFuel
Tempo
Texaco
Tri-Par Qwik Stop
Valero
76
Aloha
ARCO
Beacon
BP/Amoco Ultimate
BP Regular
BP Silver
Break Time
Cenex
Chevron
CITGO
Conoco
Co-op
Costco Gasoline
CountryMark
CountryMark Plus
Diamond Shamrock
Esso
Express
Exxon
Hele
Holiday
Kwik Star
Kwik Trip
Kwik Trip Express
Mahalo
Marathon
Metro Petro
MFA
Mobil
OAAI
Ohana Fuels
Petro-Canad
Phillips 66
PUMA Energy Caribe
QT
QuikTrip
Road Ranger
Shamrock
Shell
Sinclair
Standard
Sunoco Ultratech
SuperAmerica
SuperFuel
Tempo
Texaco
Tri-Par Qwik Stop
Valero
Last edited by royal flush; Feb 21, 2018 at 06:40 PM.
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
Good question. I do know a few years ago a local station was fined for not having the right gas, so someone must be checking them.