Fuel Options
Thread Starter
Keeping Cool
Joined: Jan 2006
Posts: 488
Likes: 2
From: Redondo Beach CA
Fuel Options
Well with the price of gas lately I was wondering if any one uses regular unleaded in their cars? I have never used regular in any of my high performance cars, but I do put it in my truck and my wifes expedition. I would just hate to start having engine problems ie., pinging, knocking, run on.
Thanks
Thanks
Racer
Joined: Jul 2005
Posts: 397
Likes: 0
From: Weston Fl
Originally Posted by jrzyvet
Well with the price of gas lately I was wondering if any one uses regular unleaded in their cars? I have never used regular in any of my high performance cars, but I do put it in my truck and my wifes expedition. I would just hate to start having engine problems ie., pinging, knocking, run on.
Thanks
Thanks
~Derek
Team Owner
Joined: Aug 2004
Posts: 22,290
Likes: 207
From: Sussex,Wi
2023 Corvette of the Year Finalist - Unmodified
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Originally Posted by 4Ever21
I use regular unleaded in my '85. I thought you were supposed to use it in older Corvettes. Can I use Premium and benefit from it in my car?
Safety Car
Joined: Nov 2005
Posts: 4,590
Likes: 48
From: W MI
The only benefit of premium to a stock engine is prevention of knocking and pinging.
On a modded engine, premium is a must. I am interested what the Vette's are supposed to run. I'm going to be going on a White Castle run once it's nice out(I live 2.5 - 3hrs away from one), and want to calculate cost of the trip. If it's premium, it'll cost a Slider Meal more!
GT6
On a modded engine, premium is a must. I am interested what the Vette's are supposed to run. I'm going to be going on a White Castle run once it's nice out(I live 2.5 - 3hrs away from one), and want to calculate cost of the trip. If it's premium, it'll cost a Slider Meal more!
GT6
Thread Starter
Keeping Cool
Joined: Jan 2006
Posts: 488
Likes: 2
From: Redondo Beach CA
So here is the next question. I too am afraid of the Regular Unleaded Pinging and Knocking, but do you think that one tank of regular would screw everything up enough that I would have clean it all up from the inside?
I know this sounds crazy, but I would hate to be sitting at a light and have some one attempt to race and then have the car ping all the way down the road.
I know this sounds crazy, but I would hate to be sitting at a light and have some one attempt to race and then have the car ping all the way down the road.
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Burning Brakes
Joined: Aug 2005
Posts: 772
Likes: 6
From: Huntsville AL
My 88 owners manual states:
"Your engine is designed to operate on premium grade unleaded fuel. However, with the electronic spark control system, you may use either middle or regular grade unleaded fuel at slightly reduced acceleration performance."
It further states:
"You should use a premium unleaded fuel with an octane rating of at least 91. You may use a middle grade unleaded fuel with an octane rating of at least 89 or a regular grade unleaded fuel with an octane rating of at least 87 at slightly reduced acceleration performance.
Using unleaded fuel with an octane rating of lower than 87 may use persistent, heavy spark knock."
When I first purchased my vette, I used premium fuel. After about a month I swapped to regular and never noticed any difference in fuel economy, performance, or problems. Been using it ever since w/ no knocking, pinging, or other issues.
"Your engine is designed to operate on premium grade unleaded fuel. However, with the electronic spark control system, you may use either middle or regular grade unleaded fuel at slightly reduced acceleration performance."
It further states:
"You should use a premium unleaded fuel with an octane rating of at least 91. You may use a middle grade unleaded fuel with an octane rating of at least 89 or a regular grade unleaded fuel with an octane rating of at least 87 at slightly reduced acceleration performance.
Using unleaded fuel with an octane rating of lower than 87 may use persistent, heavy spark knock."
When I first purchased my vette, I used premium fuel. After about a month I swapped to regular and never noticed any difference in fuel economy, performance, or problems. Been using it ever since w/ no knocking, pinging, or other issues.
).
Safety Car
Joined: Mar 2005
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From: Fredonia WI
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85 - regular OK
Originally Posted by jrzyvet
So here is the next question. I too am afraid of the Regular Unleaded Pinging and Knocking
Gary
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
I have an '85 and the previous owner said he's always used regular unleaded (87) and thats what I use. It runs like a dream and is very clean too. I dont experience any kind of knocking or pinging. I would have to agree with what was said about the compression ratio. The higher compression ratio engines should use a higher grade of fuel.
Racer
Joined: Jan 2005
Posts: 476
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From: Tucson, AZ. L98-85 AUTO COUPE: 120k MILES: daily driver. SOUND OFF IF YOU'VE BEEN THERE. Ex-Jumpin' Junky-82nd Airborne-2/505 PIR: 1st ID-1/16th Inf: Recon Marine Retread. GOD BLESS GRUNTS.
the 85 has 9:1 compression.
from what i saw on the goggle box the other day, the real need for the higher octane comes in when you stomp on it to stop knocking.
it's probably ok to run regular (especially in a lower cr head), untill you jump on it full throttle, get a little knock and get timing retard at the time you least want it.
come to think of it, running regular would probably be best on a long distance trip--both for economy and the reduced need for wot stomps.
froggy.
from what i saw on the goggle box the other day, the real need for the higher octane comes in when you stomp on it to stop knocking.
it's probably ok to run regular (especially in a lower cr head), untill you jump on it full throttle, get a little knock and get timing retard at the time you least want it.
come to think of it, running regular would probably be best on a long distance trip--both for economy and the reduced need for wot stomps.
froggy.
Team Owner
Joined: Aug 2004
Posts: 22,290
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From: Sussex,Wi
2023 Corvette of the Year Finalist - Unmodified
2022 C3 of the Year Winner - Unmodified
Originally Posted by parafrog
the 85 has 9:1 compression.
wot stomps.
froggy.
wot stomps.
froggy.
I still use HI-PO 87.
Pro
Joined: Oct 2005
Posts: 557
Likes: 1
From: Ottawa Ontario
Guys guys, I don't know how many times this has been explained. There's another thread on this here also. The reason for different octane gasolines is THE RATE AT WHICH THEY BURN!!!!
Higher octane gasolines burn slower than lower octane gasolines. Corvettes are engineered with higher performance therefore they have a different TIMING CURVE, therefore they require HIGHER OCTANE FUELS to decrease detonation. Follow your owners manual if you are not car savvy.
It has been said though that some corvette owners can get away with lower octane sometimes and only suffer a decrease in performance. Maybe your one of them. I wouldn't risk a hole in a piston to save a few bucks. Its up to you. By the time the detonation occurs it could be too late.
You bought a rocket. Feed it rocket fuel
Higher octane gasolines burn slower than lower octane gasolines. Corvettes are engineered with higher performance therefore they have a different TIMING CURVE, therefore they require HIGHER OCTANE FUELS to decrease detonation. Follow your owners manual if you are not car savvy.
It has been said though that some corvette owners can get away with lower octane sometimes and only suffer a decrease in performance. Maybe your one of them. I wouldn't risk a hole in a piston to save a few bucks. Its up to you. By the time the detonation occurs it could be too late.
You bought a rocket. Feed it rocket fuel
Advanced
Joined: Oct 2005
Posts: 74
Likes: 0
From: Halifax Va
Cruise-In VII Veteran
Originally Posted by thomastl
My 88 owners manual states:
"Your engine is designed to operate on premium grade unleaded fuel. However, with the electronic spark control system, you may use either middle or regular grade unleaded fuel at slightly reduced acceleration performance."
It further states:
"You should use a premium unleaded fuel with an octane rating of at least 91. You may use a middle grade unleaded fuel with an octane rating of at least 89 or a regular grade unleaded fuel with an octane rating of at least 87 at slightly reduced acceleration performance.
Using unleaded fuel with an octane rating of lower than 87 may use persistent, heavy spark knock."
When I first purchased my vette, I used premium fuel. After about a month I swapped to regular and never noticed any difference in fuel economy, performance, or problems. Been using it ever since w/ no knocking, pinging, or other issues.
"Your engine is designed to operate on premium grade unleaded fuel. However, with the electronic spark control system, you may use either middle or regular grade unleaded fuel at slightly reduced acceleration performance."
It further states:
"You should use a premium unleaded fuel with an octane rating of at least 91. You may use a middle grade unleaded fuel with an octane rating of at least 89 or a regular grade unleaded fuel with an octane rating of at least 87 at slightly reduced acceleration performance.
Using unleaded fuel with an octane rating of lower than 87 may use persistent, heavy spark knock."
When I first purchased my vette, I used premium fuel. After about a month I swapped to regular and never noticed any difference in fuel economy, performance, or problems. Been using it ever since w/ no knocking, pinging, or other issues.
My '90 manual says the same thing.