FEOA Forums banner
1 - 20 of 27 Posts

·
Registered
Joined
·
114 Posts
Discussion Starter · #1 ·
with the current rise in gas prices i began to wonder what the benefits of 93 octane vs 89 or even 87 were. i've always put 93 in the car, but a friend of mine said that since i only have a 4 cylinder and i have a low emissions car i may get more benefits from a low octane fuel. i don't know how true that is but i know that the car performs slightly better when i use 93 but since it's so freaking expensive now i'm thinking about going to a 89 or a 87 instead. which fuel is better?
 

·
Registered
Joined
·
2,596 Posts
yeah. he's pretty much correct about what he said. the higher the octane, the better. but it 93 also beneficial more towards engines with higher output. like vettes and V8s and all that. if i were you, i'd stick with the 87. it's not like it's half octane, half water.
 

·
Registered
Joined
·
5,296 Posts
If your manual say's your car can run on 87, run 87. There is very little benefit to running higher ocatane fuel in a vehicle that doesn't require it. Higher octane fuels are required for engines built with higher compression ratio's that require a higher anti-knock (octane) rating to prevent engine damage from fuel ignighting itself due to compression temperatures (detonation). The escorts were designed to run off 87, so I see no reason to run anything other than that. Fuel producers as an incentive add more detergents and additives to higher octane fuels which help keep your engine cleaner internally and improve fuel milage somewhat. Some say you engine will run better off of higher ocatne fuel than the lower grade, but that's subjective. A properly tuned engine will run as well off of either fuel. My theory is that for the extra cost of higher grade fuel, with the money I save by bying 87 every week I can easily pay for another gallon of 87 for what little milage I would loose, and a bottle of injector cleaner every couple months is pretty cheap too :wink:

Hope that helps :D

Matt 8)
 

·
Registered
Joined
·
148 Posts
I concur completely with Matt's answer. I've read that in several places and I've also independtly tested fuel economy on my escort. In addition I've noticed no performance gains by using 93 octane fuel over 87.

I use 87 always now.

However, there is NO harm in using 93 octane fuel. If the prices were the same, I would use 93 octane fuel.

Saj
 

·
Registered
Joined
·
8,915 Posts
I concur with matt, because well, Matt is right.

Use the manufacturers recommended Octane rating in your car.

Higher octane has a higher flash point, meaning it's less susceptible to premature combustion (aka knocking, pinging).

By putting 93 into a car meant for 87 you're making the ecu run the car hotter to effectively atomize each fuel particle. A cooler car runs better.

I for one have to use at least 91 octane in the Si...damned 10.4:1 compression ratio...

All Escorts I've ever seen can use Regular (87) or mid level (89) octane, but using 91+ premium is a waste of 20 cents a gallon for them.

I just remembered this article I read.

http://www.hondaswap.com/forums/index.php?showtopic=13
 

·
Registered
Joined
·
212 Posts
As soon as it gets warmer in Pa. I'll start running 89 just so I don't have to hear the pinging on the hills. Otherwise it's 87. I also have a Ducati and guy's who dyno them claim more power from 87. If you increase the CR than the octane should also rise. My 93 Mercedes has a timing module thats programed for the country of origin. Because people in U.S. buy $50,000 cars and put cheap gas in them, MB retards the timing. German folks insist on performance so they get the uprated timing module. It's basically a mater of sniping a wire or two but than I need the highest octane possible everytime or severe pinging will occur. I also have been working in the petroleum business for 25 years and the trend at gas stations has been one hose per dispenser and two storage tanks blending fuel at the time of purchace. As someone who works on gas stations everyday I rather get my gas at a station with three hoses at the dispenser and three seperate tanks in the ground. I other words not all gas stations are on the up and up.
 

·
Registered
Joined
·
2,709 Posts
Even though I run 87 octane, I always buy from reputable stations like sunoco or shell or something. I keep away from mom-and-pop stations, and old gas stations, ecause they tend to have old and outdated storage tanks. Also, make sure you don't buy from a station that recently had its storage tanks filled, because it kicks up sediment and such in the tanks- or so I have heard.

Most people think that gas is gas is gas. Not true. In my experiences, I've tried stuff from mom-and-pop stores and sunoco gas, and the sunoco gas gets better gas mileage and also runs more smoothly in similar conditions. I'm more than willing to spend more to buy from a good station than to save the extra 5 cents to get it from a cheezy little corner store.

I honestly don't know for sure that what I said above is correct, but I'm going by my limited experience and intuition.
 

·
Registered
Joined
·
1,078 Posts
Ignatz said:
My 93 Mercedes has a timing module thats programed for the country of origin. Because people in U.S. buy $50,000 cars and put cheap gas in them, MB retards the timing. German folks insist on performance so they get the uprated timing module. It's basically a mater of sniping a wire or two but than I need the highest octane possible everytime or severe pinging will occur.
Boo. My '88 TBird has a switch on the dash for "Regular" or "Premium" gas and adjusts the timing properly.
Ignatz said:
I rather get my gas at a station with three hoses at the dispenser and three seperate tanks in the ground.
All gas delivery trucks have 2 tanks. 87 and 92/93. If you have 89, it's a mixture of the two, whether the mixture happens when the gas in put into the big tank, or whether the mixture happens when it's put into your tank, I doubt it really matters.

Siragan - Everything you said was correct. :) We don't have sunoco down here, but BP and Texaco are all I'll ever use again. STAY AS FAR AWAY FROM WAWA GAS AS YOU CAN.
 

·
Registered
Joined
·
212 Posts
Delivery trucks or tank trailers can have up to 4 compartments to carry whatever octane rated gas they want. Maybe the terminals blend there own mid-grade,but I do know the driver can leave the terminal with 89. Sunoco inspects their stations for octane accuracy. Gas is gas when it comes out of the pipeline most agree, but branded additives are used to make some better than others. Chevron is not available anymore in Pa. so I add 35ml of Chevron Techron to my wifes Benz every tankfull and eliminated injector problems. I try to get Sunoco whenever I can. The Chevron website has interesting facts on Techron and their gas. Detroit's big three truck in Chevron gasoline for emission and general testing because the gas in Michigan obviously is'nt as good. Check out the cool cars from the TV ad's.
 

·
Registered
Joined
·
5,296 Posts
siragan said:
In my experiences, I've tried stuff from mom-and-pop stores and sunoco gas, and the sunoco gas gets better gas mileage and also runs more smoothly in similar conditions.
Yeah, I've noticed that as well. I've found that I get about 1-2mpg better milage with Esso/Imperial than PetroCan, both 87 grade. The price difference is almost zero between the two.

Matt 8)
 

·
Registered
Joined
·
735 Posts
I dig Chevron, the price makes no difference to me when choosing between Shevron and Shell/Texaco. As for the octane thing, I use 92 because I did the advanced timing mod thinger. I went to Montana last month and they only had 91 octane. Montana makes the baby jesus cry.
 

·
Registered
Joined
·
2,188 Posts
I live at 3300'. Whenever I'm just driving back and forth from work (a level commute), I'll just use 87 octane. If I know I'm going off the mountain for anything I'll start filling up with 93 so that I have some for the trip back up the mountain. The load on the engine coming back up the mountain leads to pinging, so I try to avoid it with the higher octane fuel.

Also, whenever I'm autocross-ing I'll fill up with 93 so that I don't get into any trouble when I bog the engine on some of my not-so-perfect launches.

The higher the octane the more stable the fuel is. The more stable the fuel is, the more compression, spark &/or heat it takes to ignite it. Generally you will get better mileage out of lower octane fuel because it gives up energy more readily.

The number of cylinders you have is irrelevant to the type of fuel you put in your car. Your friend was dead wrong to be citing the number of cylinders.

Many low-emissions vehicles (LEV) require higher octane fuel because they result in lower combustion chamber temperatures.. and therefore less NOX. An escort is not a LEV.
 

·
Registered
Joined
·
822 Posts
i for one am a firm believer in the perfection of 87 octane gas for stock scorts, because quite frankly, all you're doing by running higher octane is burning a hole in your pocket, and as james said, making the ecu run the engine hotter.... well, ya see, the 87 octane, depending on where you get it, is usually not quite as clean as 93+ octane fuel..... but this is why they make fuel system cleaner..... meant to use it every 3 months/3000 miles, or whenever you change your oil and whatnot..... well, i have used the chevron feul injector/fuel system cleaner, and it seemed to work pretty well, and it keeps your fuel system clean..... but unless you have a high compression engine with a turbo, or you're running a new ford lightning @ 8psi or whatever they run at now (i believe it's 8 psi with the stock supercharger), then you would NEED to be running premium. for every couple psi or something, you need so many octane points, idr, i read something about it, just can't really remember.

http://auto.howstuffworks.com/gasoline.htm

go through that whole thing to learn how it all works (www.howstuffworks.com is a GREAT website for ppl that don't know stuff lol)
 
1 - 20 of 27 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top