High Octane fuel
Camel Trophy
Joined: Nov 2009
Posts: 4,079
Likes: 227
From: IL
This is like asking what's the best oil.
I run 93 in one disco and 87 in another. PT Schram will tell you he runs E85. I think it's more important bro just pick one grade and stick with it.
Premium used to be $.20/gallon more than regular. Now it's usually $.50/gallon more which starts to add up a lot faster.
I run 93 in one disco and 87 in another. PT Schram will tell you he runs E85. I think it's more important bro just pick one grade and stick with it.
Premium used to be $.20/gallon more than regular. Now it's usually $.50/gallon more which starts to add up a lot faster.
Camel Trophy
Joined: Nov 2009
Posts: 4,079
Likes: 227
From: IL
My '98 I've only ever put Premium in since I've owned it since '09. The ONE time I forgot and put Regular in it totally ran like crap and even threw a code I believe.
My '96 was owned by my brother for about 6 years and by me for the last year. He only ever ran regular and I've stuck with regular and it seems to run great. I haven't tried Premium in it for fear that it will run much better and I'll want to do it all the time. Ignorance is bliss, right?
I'll have my fleet down to 1 within a year and then I'll run Premium in it for the little I will drive it.
Thread Starter
|
Rock Crawling
Joined: Apr 2013
Posts: 257
Likes: 0
That's exactly why I was asking. I use mine for a DD. I'm burning thru 2 tanks per week. I know my crappy mileage is even more crappy now that I put the bigger tires on. I guess I'll stick with the pricey stuff, I don't want to upset the already sensitive girl.
Rock Crawling
Joined: Feb 2014
Posts: 251
Likes: 2
From: Craig, Colorado and Pretoria, South Africa
See my next post on this issue - the system hid this one for a while.
Last edited by MonteroMan; Jun 27, 2014 at 05:23 PM. Reason: See the following post - intially the first did did not show
Thread Starter
|
Rock Crawling
Joined: Apr 2013
Posts: 257
Likes: 0
In simple terms:
The Octane Rating is the clue here. Your elevation above sea level determines the octane rating you should use and nothing else.
At sea level a heavier load of air is ingested into the combustion chamber and a heavier load of fuel is also required. The weight of the fuel is a seperate issue than mere weaker or richer combustion mixture as determined by elevation).
Previously this was achived by a larger amount of tetra ethyl lead in the fuel. Nowadays other heavy metal additives are used. In Europe and South Africa fuel at sea level and up to about 2,000 ft elevation is 98 Octane, and at the higher elevations you have the choice of 87 and 93 Octane.
It is a wastage to use 93 octane above elevations of 7,000 ft.
To use lower octane than 91 in high compression ratio engines below 5,000 ft. creates a risk for too high combustion temperature and possibly pre-ignition and exhaust valve, and possibly piston head damage.
The Octane Rating is the clue here. Your elevation above sea level determines the octane rating you should use and nothing else.
At sea level a heavier load of air is ingested into the combustion chamber and a heavier load of fuel is also required. The weight of the fuel is a seperate issue than mere weaker or richer combustion mixture as determined by elevation).
Previously this was achived by a larger amount of tetra ethyl lead in the fuel. Nowadays other heavy metal additives are used. In Europe and South Africa fuel at sea level and up to about 2,000 ft elevation is 98 Octane, and at the higher elevations you have the choice of 87 and 93 Octane.
It is a wastage to use 93 octane above elevations of 7,000 ft.
To use lower octane than 91 in high compression ratio engines below 5,000 ft. creates a risk for too high combustion temperature and possibly pre-ignition and exhaust valve, and possibly piston head damage.
Rock Crawling
Joined: Feb 2014
Posts: 251
Likes: 2
From: Craig, Colorado and Pretoria, South Africa
It is the weight
In simple terms:
Octane Rating refers to the weight per volume of the fuel. At sea level fuel with a heavier mass per volume is required than at 10,000 ft. Previously tetra-ethyl lead was added to achieve this heavier combustible liquid but other heavy metals have replaced lead.
In Europe and South Africa 98 octane petrol is used from sea level to about 2,000 ft. elevation and above that 87 and 93 octane is available. It is a waste to use 93 octane petrol above 7,000 ft unless in a turbo-charged gasoline engine.
Similarly, to use 87 octane in a high compression ratio engine below 3,000 ft. causes distinct pre-ignition, and the same for 93 octane below about 2,000 ft. Pre-ignition is a spontaneous ignition before the spark plugs spark, is at very high combustion temperature and causes a severe kick-back to the rising piston, with increasing damage to the exhaust valves and piston top surface.
The old 3.80 litre V-8 of the Landrover was a low compression ratio engine.
Octane Rating refers to the weight per volume of the fuel. At sea level fuel with a heavier mass per volume is required than at 10,000 ft. Previously tetra-ethyl lead was added to achieve this heavier combustible liquid but other heavy metals have replaced lead.
In Europe and South Africa 98 octane petrol is used from sea level to about 2,000 ft. elevation and above that 87 and 93 octane is available. It is a waste to use 93 octane petrol above 7,000 ft unless in a turbo-charged gasoline engine.
Similarly, to use 87 octane in a high compression ratio engine below 3,000 ft. causes distinct pre-ignition, and the same for 93 octane below about 2,000 ft. Pre-ignition is a spontaneous ignition before the spark plugs spark, is at very high combustion temperature and causes a severe kick-back to the rising piston, with increasing damage to the exhaust valves and piston top surface.
The old 3.80 litre V-8 of the Landrover was a low compression ratio engine.
Thread
Thread Starter
Forum
Replies
Last Post
