Gas
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Joined: Nov 2007
Posts: 93
Likes: 0
From: Carolina Beach NC
I use 93 octane only ... from a reputable station. I once mistakenly filled it with some 91 octane while on a road trip. Maybe it's just me, but I noticed a dip in performance and fuel economy using the lower grade.
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93 Octane is all I use.
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Drifting
Joined: Oct 2006
Posts: 1,694
Likes: 0
From: Beaverton Oregon
1986E, Owners Manual, 87 Octane recommended. Using Premium fuel is actually bad as the low compression engine cannot utilize the higher octane fuel. You may as well throw the extra money into the hands of the guy standing by the freeway offramp rather than spend it in higher octane fuels.
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
Recently i've been putting 87 in the LT1....runs fine and i don't need the extra performance of 93 along with the cost.
I'll probably start back up once summer hits though since it only cost what?.... $3 extra for 93 about...
I'll probably start back up once summer hits though since it only cost what?.... $3 extra for 93 about...
Thread Starter
Instructor
Joined: Nov 2007
Posts: 108
Likes: 0
From: Waukesha WI
Well, it's only about $.50 a gallon more here. Just curious as i'm a student and ANY extra money that can go somewhere else helps. I thought that it was a lower compression engine and didn't need the higher octane, but was just curious. I'll try the 87 and see what it does. I had been putting 91 or 93 in it before, but will try 87 and see what it does.
Instructor
Joined: Aug 2007
Posts: 230
Likes: 1
From: Covington GA
The '86 models are designed to run on 87 octane according to the owner's manual, so that's what I run. If I had modified it for more aggressive timing or something I might run premium, but if the engine runs happily on 87 octane and doesn't ping I don't expect 93 octane to help it at all.
I have, however, noticed that it doesn't always run too well on certain grocery store brands of gas. So I've quit putting no-name gas in it and try to stick with reputable gas brands. First car I've ever owned that did that...
I have, however, noticed that it doesn't always run too well on certain grocery store brands of gas. So I've quit putting no-name gas in it and try to stick with reputable gas brands. First car I've ever owned that did that...
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
Well, it's only about $.50 a gallon more here. Just curious as i'm a student and ANY extra money that can go somewhere else helps. I thought that it was a lower compression engine and didn't need the higher octane, but was just curious. I'll try the 87 and see what it does. I had been putting 91 or 93 in it before, but will try 87 and see what it does.
But here it's only $.20 more for premium and if i fill up 15gallons thats about $3 extra of $50 which isn't that much more for the piece of mind for me. I just got lazy a few times and put it in there.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
I tried running 87 octane in my 87 but I did get some pinging under load. Cruising on the freeway or simply driving around town was not a problem. The owner's manual does specify a minimum of 91 octane unleaded premium but 87 can be used "with decreased engine performance".
I don't buy the cheap gas like that from Safeway, Costco, or even the convenience stores like AM-PM/Arco even for my truck. They typically do not have the additives and detergents like that found in Chevron, Texaco and other 'name-brand" gasolines. You could add a bottle of Techron on occasion to keep the fuel system clean, but it's just easier to get it in the gasoline.
I don't buy the cheap gas like that from Safeway, Costco, or even the convenience stores like AM-PM/Arco even for my truck. They typically do not have the additives and detergents like that found in Chevron, Texaco and other 'name-brand" gasolines. You could add a bottle of Techron on occasion to keep the fuel system clean, but it's just easier to get it in the gasoline.
Race Director
Joined: Dec 2005
Posts: 13,515
Likes: 12
From: Fisher, IL
I tried running 87 octane in my 87 but I did get some pinging under load. Cruising on the freeway or simply driving around town was not a problem. The owner's manual does specify a minimum of 91 octane unleaded premium but 87 can be used "with decreased engine performance".
I don't buy the cheap gas like that from Safeway, Costco, or even the convenience stores like AM-PM/Arco even for my truck. They typically do not have the additives and detergents like that found in Chevron, Texaco and other 'name-brand" gasolines. You could add a bottle of Techron on occasion to keep the fuel system clean, but it's just easier to get it in the gasoline.
I don't buy the cheap gas like that from Safeway, Costco, or even the convenience stores like AM-PM/Arco even for my truck. They typically do not have the additives and detergents like that found in Chevron, Texaco and other 'name-brand" gasolines. You could add a bottle of Techron on occasion to keep the fuel system clean, but it's just easier to get it in the gasoline.
Instructor
Joined: Jan 2008
Posts: 138
Likes: 0
From: Ohio
now i've always heard you get knocking/pinging when using cheap gas but i guess maybe since i'm not looking/listening for it it could be there. Do you feel it in the actual engine part or does it sound more like out the exhaust? I guess i should do a test to see if it's doing it or not. Any suggestions how?
just my take.
Drifting
Joined: May 2004
Posts: 1,543
Likes: 1
From: Levittown NY
You should always use the lowest octane you can without detonation. If you use a higher octane than needed you will actually hurt performance. The octane number is the measurement of the resistance of gasoline to auto-ignite. The names they give gas is just stupid (premium, super, etc.). It's a marketing campaign to get people to spend money on something they don't need.
