I was hoping one of yall could do one of those HP test thingys with the Premium Fuel, isn't it 97 octane? Yeah, well I will greatly appreciate it, thanks. Oh and by the way, I didn't get the Expo, maybe 2005 with the new motor? Thanks.

 

For this engine, high octane fuel will not have any HP advantage. In fact it may lower your horsepower. Higher octane gas has less energy content, and is harder to ignite. The purpose of this is to keep high performance (as in high compression) engines from pinging (pre-detonation).

Bottom line: Read your owners manual. This is a relatively low compression engine and using high octane gas will give you no benefit. Owners manual states what it needs, 87 octane.

 

I agree on not using high octane fuel in a stock engine. No benefit other than a more expensive fuel.

Now if you use a chip designed to run on high test thats a different story.

 

Performance wise you won't see much difference. The one thing we see lots of is hard starting on higher than recomended octane. The start, but you often have to actually turn them over instead of just bumping the key. However, on my wife's Taurus vehicles I run Premium about every 3rd tank to get the injector cleaner and other additives.

 

the owner's manual specifically warns against putting premium fuel in this truck. it burns hotter than the cheaper stuff and does nothing for you. no reason to put more stress underhood with higher temps. i will never put premium in my truck.

 

AAA says that all grades of fuel typically have the additives, but they only advertise them in the premium fuels to make more money.

They could be wrong, but it makes sense to me.

 

My truck came with a full tank of premium. The salesman filled it up before our test drive. When I asked him about it, he said that Ford recommends Premium fuel for the first 500 miles! Can you believe that? Needless to say, I just chalked this up to one more example of how salesmen don't know the features of the vehicles they are selling. BTW - the first tank of gas that I put in was 87.

 

"but they only advertise them in the premium fuels to make more money"

Yes, this is correct. Companies have gotten into trouble about this.

 

High octane fuel actually burns cooler.

Lower energy content = lower combustion temperatures

This is the whole point behind high compression engines requiring high octane fuel. If you put lower octane gas in a high compression engine then the combustion chamber temps will go up causing the fuel/air mixture to ignite before the spark plug fires.

But you are correct in that premium fuel should not be used.

I will also echo what others have said. Premium fuel does not have any extra or "special" additives in it that are different then regular 87 octane. All gas grades are required by law to have these additives to keep engines burning cleaner and more efficiently. Clogged injectors = bad fuel economy/higher emmisions, additives in all grades of gas keeps the injectors clean, saves fuel and lowers emissions