Premium fuel vs. regular fuel

dslater524 · 08-19-2005, 01:11 AM

There's a Chevron station just outside of town that sells Premium (90 octane) fuel for $2.50/gal. Not bad especially with the Techron. So I decided to fill her up with the 90 octane, thinking it might show up in performance a bit and on the mpg. Guess I was wrong.

I haven't noticed any difference in the performance but the mpg went from 14.1mpg on regular to 13.7 on premium. In town and some hwy. What's up? I thought for sure it would improve a little...maybe enough to compensate for the price difference.

Any thoughts or do I need to give it longer to work? That was on the 1st 1/2 tank...refilled it with premium again.

orangepeel · 08-19-2005, 03:46 AM

That sounds about right.The main thing to do is by quality gas at a station that has a lot of traffic and keeps fresh gas.

Contrary to popular belief, the octane ratings alone doesn't determine how fast the fuel burns.The flame speed,energy content,and amount of tuning done to the engine (compression,timing,combustion chamber)has more to do with determining that.The reason I say that is because lots of people think octane determines the burn speed which in return is supposed to make for more horse power,and better fuel economy.WHen in reality the octane number is determined by the fuels ANTI-KNOCK capability, also known as AKI (anti-knock index), NOT how "explosive" it is.

RON+MON/2

real_texan77 · 08-19-2005, 08:24 AM

Quote:

Originally Posted by dslater524

There's a Chevron station just outside of town that sells Premium (90 octane) fuel for $2.50/gal. Not bad especially with the Techron. So I decided to fill her up with the 90 octane, thinking it might show up in performance a bit and on the mpg. Guess I was wrong.

I haven't noticed any difference in the performance but the mpg went from 14.1mpg on regular to 13.7 on premium. In town and some hwy. What's up? I thought for sure it would improve a little...maybe enough to compensate for the price difference.

Any thoughts or do I need to give it longer to work? That was on the 1st 1/2 tank...refilled it with premium again.

I would not pay for premium and you only get 90 octance, here in Texas its 93 octane for premium.

Elbo · 08-19-2005, 08:35 AM

My Titan gets much better gas mileage with the 93 here in Texas. I was very excited bout this, but when I did a cost per mile comparison, the difference was like half a cent or something per mile cheaper with the 93. A lot of it depends on the price difference between the higher octane and the lower.

Since then I almost get the 87, just because it doesn't hurt as much when filling it up.

DeeDubya · 08-19-2005, 08:59 AM

No difference in my truck. Right now I'm checking mpg with Shell 89 which is their "plus" or middle grade. I usually average about 3 full tanks to get a good in/out of town average. Looks like it's going to be around 14mpg. I've only got 1600 miles so I'm not too worried yet. Hopefully it will improve.

devilpuppy · 08-19-2005, 09:19 AM

I have done some research on the types of gasoline. In my experience the higher octane gasolines are only beneficial if your vehicle has something like a supercharger or is a really high end vehicle, (corvettes,vipers,etc). For my money, I consider it a waste of time.

Bayou Titan · 08-19-2005, 09:34 AM

I think it is a waste of money to buy premium gas in an attempt to get better gas mileage. Any increase in fuel economy would be barely noticeable and certainly would not offset the higher cost of premium gas.

Personally I don't pay that much attention to the gasoline additive hype like Techron. Does anyone know how many parts per million of Techron is actually added to a gallon of gas and does that amount make any difference? There are thousands of chemicals and extracts added to consumer products that have little or no effect other than marketing hype.

orangepeel · 08-19-2005, 09:55 AM

Quote:

Originally Posted by devilpuppy

I have done some research on the types of gasoline..

Yeah,but most people don't do any research,or let facts get in the way.

KTMNealio · 08-19-2005, 10:50 AM

Quote:

Originally Posted by orangepeel

Yeah,but most people don't do any research,or let facts get in the way.

I heard about a guy who put premium in his Neon and it would smoke the tires for miles....

- Nealio

dslater524 · 08-19-2005, 11:46 AM

Quote:

Originally Posted by Bayou Titan

I think it is a waste of money to buy premium gas in an attempt to get better gas mileage. Any increase in fuel economy would be barely noticeable and certainly would not offset the higher cost of premium gas.

Personally I don't pay that much attention to the gasoline additive hype like Techron. Does anyone know how many parts per million of Techron is actually added to a gallon of gas and does that amount make any difference? There are thousands of chemicals and extracts added to consumer products that have little or no effect other than marketing hype.

You may be right on this, but I know that Techron is good stuff. As to the amount in a gallon of fuel, I have no idea. Probably wouldn't clean things up, but I think it's enough to keep things clean. In my vette, I would add a bottle of Techron (expensive stuff) about every 4 tankfuls. I could really tell the difference. However, on the Titan, everything is already clean (new), so I probably wouldn't notice a difference due to the Techron...just preventative. The premium fuel however, I felt might give me a little better performance. Didn't feel anything different, but then again, the truck is already quick. After this tank, I'll probably go back to regular ol 87 octane.

*BAT1* · 08-19-2005, 12:01 PM

Quote:

Originally Posted by dslater524

There's a Chevron station just outside of town that sells Premium (90 octane) fuel for $2.50/gal. Not bad especially with the Techron. So I decided to fill her up with the 90 octane, thinking it might show up in performance a bit and on the mpg. Guess I was wrong.

I haven't noticed any difference in the performance but the mpg went from 14.1mpg on regular to 13.7 on premium. In town and some hwy. What's up? I thought for sure it would improve a little...maybe enough to compensate for the price difference.

Any thoughts or do I need to give it longer to work? That was on the 1st 1/2 tank...refilled it with premium again.

For God's sake, do a search. This has been gone over and over and over. It doesn't take much to find your answer (there is none) if you look hard enough.

Yomama · 08-19-2005, 12:27 PM

Why pay extra for the anti-knock benefit when you could get the same result with water.....Premium is for high compression to prevent pre-ignition, knock or dieseling. You can accomplish the same feat with a spray of H2O. Like the Stillen that is only at 6 PSI to go higher then that they would need intercooling or H2O to keep it from pre-ignition. You are wasting money your money on premo....

keiffers · 08-19-2005, 01:23 PM

I've only put premium in my Titan less than 5 times in the year I have had it and I never noticed much of a difference other than in cost. When I do put premium in it, its not very often. I do it merely to so called 'clean out' the injectors and tank, but regular unleaded does the job for me

Yomama · 08-19-2005, 01:41 PM

Quote:

Originally Posted by keiffers

I've only put premium in my Titan less than 5 times in the year I have had it and I never noticed much of a difference other than in cost. When I do put premium in it, its not very often. I do it merely to so called 'clean out' the injectors and tank, but regular unleaded does the job for me

My wifes last car was an Oldsmobile Aurora, high performance engine and required premium (didn't know that till I called on the insurance) anyway, after about 6 months the fuel regulator started leaking. I had taken it into GM to find out what was wrong, the mechanic recommended that after I replace the fuel regulator he said I should NOT run premium, because it would eat through the seals quicker. I stopped running premium and dropped it down to the middle grade fuel, never had any problems after that, so maybe premium does clean.....then again maybe too much....

Armada · 08-19-2005, 01:51 PM

Quote:

Originally Posted by BAT1

For God's sake, do a search. This has been gone over and over and over. It doesn't take much to find your answer (there is none) if you look hard enough.

What he said.

There's tons of stuff here on this. And one tank is not going to be enough to prove or disprove anything as subtle as a few points of octane. Just mininscule difference is driving style and conditions (like whether you drive the exact same miles per hour, amount of A/C cycling, etc.) can result in that much swing.

Honest, well meaning guys are coming down on all sides of this issue. I can't say that either side is wrong on the mileage issue, but I doubt there is any meaningful mileage difference.

There can be a slight horsepower increase, but only 10 horses, if you go to 91 or higher octane. Even then those extra horses are absent most of the time. They seem to show up only under conditions in which timing would be asked to advance further than it can do with regular fuel. That is usually only at wide open throttle, or when pulling a heavy load.

Just my two bits.