Octane test report
Melting Slicks
Joined: Apr 2008
Posts: 2,621
Likes: 242
From: Russell Ontario
St. Jude Donor '09
It sure is I love the non winning arguments, I've been twisting wrenches for 25yrs and you can have the same argument with the syntec stuff , oils, gas, tires, I ran an old Cutlass , and never changed the oil on it once , just topped it off once in a while , had the car I think 6 yrs and when it all rusted out the engine went in a 1/2 ton pick up. I told the guy "you don't want this engine" he took it and ran the truck another 2 yrs. 
Team Owner
Joined: May 2006
Posts: 21,473
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From: Palmdale, Ca----- 2009 Cyber Gray 4LT A6 F55 452 RWHP 422 RWTQ- RIP 1998 C5 734 RWHP & 585 RWTQ-----
Best way and safest way is to SCAN Log your Vette between fill-ups with a data logger - HP Tuners etc.!
This will allow you to see what is "REALLY" going on - it's up to you "BUT" you will be surprised what it does and what you don't feel when the PCM pulls timing because of knock count
That will be the true test -
I can't run less than 91 in mine (not stock)
Let us know what you find and how much you really save by "NOT" using Super Unleaded fuel grade - especially looking forward to the Scan Logs
Thanks,Matt
This will allow you to see what is "REALLY" going on - it's up to you "BUT" you will be surprised what it does and what you don't feel when the PCM pulls timing because of knock count
That will be the true test -
I can't run less than 91 in mine (not stock)
Let us know what you find and how much you really save by "NOT" using Super Unleaded fuel grade - especially looking forward to the Scan Logs
Thanks,Matt
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Joined: Sep 2011
Posts: 70
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From: DFW Area Denton County
Advanced
Joined: Sep 2011
Posts: 70
Likes: 0
From: DFW Area Denton County
Melting Slicks
Joined: Apr 2008
Posts: 2,621
Likes: 242
From: Russell Ontario
St. Jude Donor '09
OK I'm getting a little scared now so maybe I'll convert my power train to a PRIUS , that my friend swill resolve the timing thing
I may have to look into this HYDRAZINE , can you buy that in Canadian litres
I may have to look into this HYDRAZINE , can you buy that in Canadian litres
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Joined: Sep 2011
Posts: 70
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From: DFW Area Denton County
Team Owner
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From: Dear Karma, I have a list of people you missed.
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15-'16
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Melting Slicks
Joined: Apr 2008
Posts: 2,621
Likes: 242
From: Russell Ontario
St. Jude Donor '09
On page 5-4 of my driver's book 2004 corvette, it says"use premium gas with a posted oct. of 91 or higher for best performance" You may also use middle grade or regular unleaded gas rated at 87 or higher , but your veh. acceleration may be sligtly reduced .If the oct. is less than 87 you may get a heavy knocking noise when you drive . If this occurs use a gas. rated at 87 or higher, asap other wise you may damage your engine. 
there it is 87 or higher
there it is 87 or higher
Team Owner
Joined: Jan 2009
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From: Somewhere in Mo
St. Jude Donor '09-'10, '14
On page 5-4 of my driver's book 2004 corvette, it says"use premium gas with a posted oct. of 91 or higher for best performance" You may also use middle grade or regular unleaded gas rated at 87 or higher , but your veh. acceleration may be sligtly reduced .If the oct. is less than 87 you may get a heavy knocking noise when you drive . If this occurs use a gas. rated at 87 or higher, asap other wise you may damage your engine.
there it is 87 or higher
there it is 87 or higher
But as it also states, 91 or higher is recommended so we also can't twist the book around and assume it is stating by all means use 87 either.
Daily driving I'm sure it's fine, but I'm a member of that He-man train of thought and I will use 91 or higher. On rare occasions I have used 89 because with fuel prices so high, they aren't selling as much 91 so it gets stale. I use 89 and 91 in my Northstar and I actually get better mileage with 89 for this reason.
Melting Slicks
Joined: Apr 2008
Posts: 2,621
Likes: 242
From: Russell Ontario
St. Jude Donor '09
I used it before with no real difference in the gas mileage ,I also tried it on my 80 before and after the dyno run , and beside a little ping on regular it ran 221hp at the wheels with 91 octane and the next time on 87 octane it ran 219 hp at the wheels no big difference.
Burning Brakes
Joined: Aug 2010
Posts: 1,148
Likes: 22
From: Portland OR
I remember the days when Chevron had what they called the white pump which they sold 100 octane from.I wish they had it now.VA-VA-VOOM.I won't run anything but 91 chevron premium in my vette.What is sad is these oil changing businesses have got everyone changing their oil every 3000 miles and that is a terrible waste of the product and they are taking advantage of women and elders.Thats my $.02.
FRED
FRED
I'd run 91 in mine too if it was not 15cents a litre more , that's just too much , they would sell alot more if they had a decent price .
Intermediate
Joined: Feb 2012
Posts: 42
Likes: 0
From: Charlotte NORTH CAROLINA
Love my corvette and I choose to run 93 in it but GM clearly states that is for "best performance". If I felt like it, I would be perfectly comfortable trying lower octane 89 or 87.
I guess I'm a "it's just a car" owner. I think it's an awesome $19k car but would never even have considered it at $50k.
Cracks me up that so many people on these threads think they can decide who is worthy to own a corvette.
Melting Slicks
Joined: Apr 2008
Posts: 2,621
Likes: 242
From: Russell Ontario
St. Jude Donor '09
no kidding I guess the more people pay for cars the higher octane you need to just "put" around town . I much prefer to spend money on important things like beer and Travel. 
Tech Contributor
Joined: Dec 2003
Posts: 19,384
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From: Horncastle Lincolnshire, England
2023 C5 of the Year Finalist - Unmodified
The one question I always have is if a high compression LS1/LS6 doesn't need high octane gas, what engine does? Why is it on sale?
Team Owner
Joined: Jan 2009
Posts: 73,568
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From: Somewhere in Mo
St. Jude Donor '09-'10, '14
I remember the days when Chevron had what they called the white pump which they sold 100 octane from.I wish they had it now.VA-VA-VOOM.I won't run anything but 91 chevron premium in my vette.What is sad is these oil changing businesses have got everyone changing their oil every 3000 miles and that is a terrible waste of the product and they are taking advantage of women and elders.Thats my $.02.
FRED
FRED
I said yep, there ya go,