Premium Gas?

[Mickey]

Originally Posted by polcat

My job in the military is Fuels. In my job we have to sample and Lab test different grades of fuel from Jet fuel to diesel to mogas (or unleaded fuel) to make sure they pass certain standards. The truth is that the different grades of unleaded gasoline have different "Flash points". This is the difference that your engine sees. When your engine flashes at different temperatures it directly effects the timing of the engine. Although this is so minute by scale, over time your engines ECU learns through sensors, the time at which you cylinder flashes, in turn adjusting the other components accordingly. Higher octane gas burns hotter and faster, which creates more power and a cleaner burn.
Bottom line is there are differences in Octane and the higher the octane (within limits to your ECU tune) the easier and better your engine will run
The good things about todays cars/trucks are the ECU's are better tuned for todays crappy gas. You will see suddle differences between grades, but they are there. Hope that helps a little.

Just be glad you dont have to use Bio-diesel. That crap sucks!!!

Great input. My second trip didn't evaluate well. Increase .1 mpg using premium. I want to belive my response is better than before. i like the way it's put above hotter faster and cleaner. So we will change to premium for now to see how things go for awhile. Hell what's another $4.00. I don't smoke much less drink or yeah I know I just won't get another mod for awhile....

[polcat]

Well I have to say I am not to pleased with the overall gas millage on this 900 mile trip. I was hoping to be at least 18 mpg, but I was steadily around 15.5-16.3mpg the whole way. I was averaging around 80 mph using mid grade. If I was lucky I could get 350 miles to each tank. Traffic was cruising around 75 so I needed to be a step ahead. I just got my exhaust done the day before also. I went with a flowmaster 40 series with 4"tips 45 degrees from the bumper. A little cabin drone, but I like that. I didn't have a base line to go off of, but I still thought I would get better than that. lol Awe well, what can you say....its 381 hp that still gets better gpm's than my Sierra did!!

[Mickey]

Originally Posted by polcat

Well I have to say I am not to pleased with the overall gas millage on this 900 mile trip. I was hoping to be at least 18 mpg, but I was steadily around 15.5-16.3mpg the whole way. I was averaging around 80 mph using mid grade. If I was lucky I could get 350 miles to each tank. Traffic was cruising around 75 so I needed to be a step ahead. I just got my exhaust done the day before also. I went with a flowmaster 40 series with 4"tips 45 degrees from the bumper. A little cabin drone, but I like that. I didn't have a base line to go off of, but I still thought I would get better than that. lol Awe well, what can you say....its 381 hp that still gets better gpm's than my Sierra did!!

Doing 80mph I got 17.3mpg. in my 400 mile round trip. Doing 60mph I got 22.5 on a 360 mile trip.

[polcat]

What the hell am I doing wrong? lol

[intensebluert]

Originally Posted by polcat

What the hell am I doing wrong? lol

You're going to notice a mpg difference from 60mph compared to 80mph, even seventy.

[polcat]

I guess my foot is a little to heavy in the beginning then. I do enjoy that power up front! lol

[Mickey]

Originally Posted by polcat

I guess my foot is a little to heavy in the beginning then. I do enjoy that power up front! lol

Polcat I also have an AFE CAI along with Borla XS complete duals along with
4" rolled/angled SS Tips.

[polcat]

I wish I had the CAI. I had a custom exhaust set up. There is a really great shop in my town that does a lot of vetts and hotrods. I went with the 40s Flowmaster and and those awesome tips and paid only $370.00. He painted all the pipes before the tips black. It looks better than stock under there! lol
I have to convince the wife to get the CAI before the step bars. I dint think thats going to fly considering she is 3 months pregnant. lol She can barley get in my truck now.

[Mickey]

Originally Posted by polcat

I wish I had the CAI. I had a custom exhaust set up. There is a really great shop in my town that does a lot of vetts and hotrods. I went with the 40s Flowmaster and and those awesome tips and paid only $370.00. He painted all the pipes before the tips black. It looks better than stock under there! lol
I have to convince the wife to get the CAI before the step bars. I dint think thats going to fly considering she is 3 months pregnant. lol She can barley get in my truck now.

Understand get the bars. @ reasons for that. 1st think of your newborn and wife. 2nd the truck will be there for the long haul. You have time. Like 6 months.

[Nukedog]

Lots of (bad) info in this thread and very little good. Not much can be proven without a dyno and someone who can alter timing on this engine. You CAN get a difference in mileage (not related to octane rating) by using better quality gas. I have verified over and over that i consistently get the best gas mileage from Chevron and get worse mileage from Hess. Like someone said before you can google the "octane myth" and learn something. These motors are 10.2 CR so they are relatively high for a everyday usage engine so they may very well benefit from 89/91 or even 93. They also may not and they certainly will get less mileage with E10 as compared to regular petrol...

[Mark-5.7]

The Tundra computers may alter the timing (advance it) with higher octane & less knock from the knock sensors. I don't think anyone has proven or disproven this yet so premium gas is worth a try on these even if it's just a bit more power until we get a TUNER!

[polcat]

You can google myths all you want to. There are way to many variations in "getting good gas mileage". Different companies use different detergents in their fuel. Some clean better without effecting its core components, some don't. If you go to fuel refineries and see how large their tanks are, were talking millions of gallons per tank, its easy to see how the fuel can start to "break down" by the time it takes to get to your car/truck. The fuel is sampled at the refineries and it could take weeks to get to your corner gas stations. Stations do not require purity tests upon delivery. Basically each delivery can slightly vary in quality. I to have had better results from using Chevron gas. But I wouldn't say that there is bad info on this tread when you have not supported your reasons. Compression in a vehicle has zero to do with your gas mileage. A low compression car still burns the same way a high compression car will. Common sense tells you a larger cylinder will require more air/fuel to compress, but it still has the same effect on every engine.
I don't want to sound like a dick, but I have been doing this for ten years and have personally been to different refineries for such problems that can occur from bad fuel. If we issue bad fuel, people die! We take this seriously.

[Mickey]

Originally Posted by polcat

You can google myths all you want to. There are way to many variations in "getting good gas mileage". Different companies use different detergents in their fuel. Some clean better without effecting its core components, some don't. If you go to fuel refineries and see how large their tanks are, were talking millions of gallons per tank, its easy to see how the fuel can start to "break down" by the time it takes to get to your car/truck. The fuel is sampled at the refineries and it could take weeks to get to your corner gas stations. Stations do not require purity tests upon delivery. Basically each delivery can slightly vary in quality. I to have had better results from using Chevron gas. But I wouldn't say that there is bad info on this tread when you have not supported your reasons. Compression in a vehicle has zero to do with your gas mileage. A low compression car still burns the same way a high compression car will. Common sense tells you a larger cylinder will require more air/fuel to compress, but it still has the same effect on every engine.
I don't want to sound like a dick, but I have been doing this for ten years and have personally been to different refineries for such problems that can occur from bad fuel. If we issue bad fuel, people die! We take this seriously.

Again great post.

[polcat]

Thank you sir

[Burnout]

Won't point fingers at any post in this thread.However there is a lot more incorrect info in here than correct.

At any one given refinery most tank trucks fill up at the same nozzles as there are three.Red,white,and blue.That designates what octane goes into what tank when you get to whatever station you are going to.Whatever brand of station you are delivering too has it's own blend of a lot of different ingrediants that are punched into the computer and added to the gas as it comes out of the nozzles.Not all fuels are created equal.Some are a lot better than the others.Colder the weather is the better stuff you get in the better brands.Cheaper stations do not put all the goodies in their mix,maybe that's why it's cheaper.

In these engines we have with all the sensors,varitable valve timing,advance or retarding timeimg,depending on engine load,fuel FPPS,10.2 don't really mean we have a true 10.2.If the exhaust valves are not closing until compression has all ready started then that tears the hell out of 10.2.This is why this engine will run on lower octane fuel.Watch as the weather warms up and see how your mpg will drop as the companies go to a hot weather mix.

Some expert said about 93 burning hotter,faster,and cleaner.Nope don't work that way.The higher octane rating a fuel has the slower it burns,it will create more BTUs due to the slow burn,but if you don't have the CR and advance timing,waste of money.Proof of this is by watching NHRA drag races.You have pump gas,race gas,alcohol,and then nitro classes.Nitro has the lowest flash point,but has the highest octane,and it burns the slowest of all fuels.That's why it's so loud and throws out the big flames as it's still exploding as it leaves the exhaust valve all the way out the weed wackers.Nitro cars have to be started on pump gas and then they hit the nitro pumps

The "ONLY" way you can do better by burning 93 octane is to get an ECU programer and increase,timing and some how by pass the varitable cam timing and get the CR up to a true 10.2.But then by doing that you will have wasted all that money for all that tech and research that went into this engine.

Wanna run 93 octane,getta 7psi SC,raise the HP up to 40% and gitter done.