The rep who sold me my '05 Screw last week, told me that these engines run better on regular octane gas than premium. This is a new line of thinking on me. The reason that I ask is that on certain days of the week here, we can purchase premium octane gas for the same price as regular. Why not get cleaner gas, if the price is the same? Is there any truth to what he was telling me?

 

Here in Calgary Alberta Premium. is 10 cents a LT extra, 87 octane is 95.5 a lt...Premium flue is a better flue, if you can get it for the same price, I would use it, the best why to tell is fill up with reg,than drive the same distance with the same habbit's, than repeat with Premium, Towing/highway Premium is better, Run your truck at night when's it's cooler, big improvement in performance...cold air/high octane flue atomize better...but at 10 cents extra per lt, on a 135 LT tank in a 6000 lbs plus truck...I'm not buying it...87 octane is fine

 

Cleaner gas??
Your truck is tuned to run on 87 octane. You can buy 89, 91, 93 or 94 octane but you will not be realizing any more power or performance with it.
Octane does not provide you with more power, it only slows down detonation which enables you to run a more aggressive tune and since you do not have it you are wasting your $$$$$. Don't give the greedy oil companies any more than you have to.......Stay with the 87 octane...

 

What are you saying man??? You will get NO added benefits from running premium fuel in a vehicle tuned for 87 octane....NONE..

 

^^^
I tell people that all the time but they just don't understand the concept of octane.

 

I don't agree...

 

You don't have to.. But your wrong.....No fuel you can put into your vehicle can "CREATE" power or performance, UNLESS, it is tuned for that specific grade or type of fuel.. If that were the case people would not have to spend thousands of $$$ on modifications, they would just keep upping the octane in their vehicles until it had all the power and performance they desired-

 

okay...tell me why your right...And I tell you why your wrong.

 

Read this...click here

 

Because I have built and tuned more gasoline, methanol, and nitro-methane powered race engines than you can probably count. And you CAN NOT get ANYTHING out of an engine that the engine is not tuned for...
The question was, "should I run a higher octane fuel than 87 in my ' 05 5.4 3 valve?". The answer is still NO you should not because it WILL NOT help as the Company that builds it, that I happen to work for, has it tuned for 87 octane......Thats my answer, whats yours?????

 

Are you serious???

 

87 octane flue is grocery getter flue, point A to B...92 Octane will give more power in the coumbustion chamber with the same spark need to burn 87 octane..Because 92 octane has a slower rate of combustion, it runs cooler, has a longer burn, less energy needed to move the piston, and is more efficent than reg gas...Even with coumputer controled engines designed to run on 87 octane, The coumputer management system has a better flue to work with....I admit the extra cost of Premiun flue in day to day driving is hard to justify, but load up your truck for a camping trip, or a highway drive and see for your self.....

 

The subject of Octane can get quite involved because there are parameters that have to be considered, to come to an understanding.
Octane change in the gas tank does not result in more power by just that change alone..
It is not cleaner fuel in any way.
Gasoline no matter what octane rating, has no more BTU heat output during combustion as long as there has been no additives installed to cause a higher heat output but that is not what this thread is about.
Octane is basicly a measure of combustion speed of the flame after ignition by the spark plug.
The combustion sensitivity is affected by many things.
Compression ratio, ignition rate of advance, chamber design, air/fuel ratio, hot spots etc.
Example of high octane that does not automatically give more power.
Methenol alky, it has about half the BTU of gas but has an octane rating over 114.
So the thought of higher octane giving more power is not at all true with any fuel.
The use of alky for racing does end up making more power but it is not because it is hotter burning. There are other dynamic involved that cause it to make about 5 to 8 % more power than gasoline.
Bottom line is you need to have a background in these sciences before making to many statements.
I to run a sprinter on alky and have long time building race engines to run both gas and alky
Mac is correct.

 

87 and leave it at that..

what do you think you have anyway?

12 to 1 compression?

...zap!

save your $$$$$

 

Use 87 octane. Higher octane will actually trick your O2 sensors and make your engine demand more fuel. Your engine is not tuned for anything above 87. Follow your owners guide. Save your money. It's the oil companies that make you think the premium stuff is better for your engine and fuel system. Have you seen how much money these guys have been making the last few years? Some of that money comes from idiots that think the premium stuff is the best. Only the vehicles that call for premium should be getting premium.