1986, which octane????
Thread Starter
Advanced
Joined: Mar 2005
Posts: 51
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From: Las Vegas Nv
1986, which octane????
noticed a knock/ rattle coming from the engine of my '86 at low revs and was running it on 85 octane. So for the hell of it I went up to 91 octane and what a difference, its like a new engine.
What does everyone else run their C4's on??
What does everyone else run their C4's on??
Team Owner
Joined: Sep 2002
Posts: 22,209
Likes: 12
From: OBAMA IS HITLER
jeremy, your '86 is a 9.5:1 (ostensibly) compression vehicle. 87 octane should be the minimum. i would run 87 or 89.
91 is probably just a wallet-lightener. try all 3 and find out which your engine can tolerate the best......i'm betting 89 is your ticket
91 is probably just a wallet-lightener. try all 3 and find out which your engine can tolerate the best......i'm betting 89 is your ticket
Team Owner
Joined: Mar 2000
Posts: 83,383
Likes: 87
From: Boston, MA
Originally Posted by jeremy carl
....what a difference, its like a new engine.
Le Mans Master
Joined: Jul 2004
Posts: 7,163
Likes: 61
From: NH
St. Jude Donor '14
I run '93. The place I get gas runs out of the lower grades all the time and he sells the '93 at 87 prices when thats all he has. I just make sure I catch him on a monday / tuesday before his truck comes in. ; )
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Burning Brakes
Joined: Jan 2002
Posts: 993
Likes: 4
From: Glen Burnie MD
FWIW, the 86 owner's manual says 87 octane minimum. If you buy from a decent gas station, all grades should have the same detergents in them...
I ran just fine on 87 once I hooked up the knock sensor that some former owner had disconnected and tie-wrapped to the frame
.
[RICHR]
I ran just fine on 87 once I hooked up the knock sensor that some former owner had disconnected and tie-wrapped to the frame
.[RICHR]
Drifting
Joined: Feb 2005
Posts: 1,592
Likes: 3
From: St Louis MO
I only put about 4500 miles/yr on the car so I use 91. If it were a daily driver I would probably go with 89. As someone said on another thread, 89 is 87 and 91 mixed by the pump so you should be getting the additives in each also.
Burning Brakes
Joined: Jan 2002
Posts: 993
Likes: 4
From: Glen Burnie MD
Originally Posted by GreyHairedTopGun
All grades do not have the same additives package. The highest grade has the best package. It's not all about octane.
[RICHR]
Le Mans Master
Joined: May 2005
Posts: 5,214
Likes: 65
From: Queensland, AUSTRALIA
I use 98 octane in my 94, and always used the same in my 87, or 95 if the 98 was not available. Im not sure if you guys have 98 octane fuel over there, but here in Australia, 91 is regular unleaded, premium is 95 and OPTIMAX or ULTIMATE are 98 octane.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by Casethecorvetteman
I use 98 octane in my 94, and always used the same in my 87, or 95 if the 98 was not available.
RACE ON!!!