Gas Octane

87 - runs fine and im getting about 450 per fill up.

 

so if it burns slower does that mean better gas mileage?

 

I use 91 in the Taco and 4Runner mainly for peace of mind. I know that I'm probably just wasting money, but in both vehicles I do notice an ever so slight increase in performance, though it could just be my mind trying to justify paying up the extra $ at the pump.

 

Slower flame propagation in the cylinder does not mean better gas mileage. It means the flame "chases the piston down the hole" instead of jackhammering it down to create "pinging". Higher octane is only useful for high-compression engines to prevent pinging due to detonation. Typically used in high-performance engines where compression is greater and more air/fuel mixture is drawn (or charged to) the cylinders to create more net power per cylinder volume available. So the higher octane will burn slower which is easier on the engine than when the fuel is ignited explosively which can lead to broken and burned reciprocating parts within the engine (piston rods / pistons / wrist pins etc.). Better gas mileage as a result? Not going to happen.

 

Exactly! Which is why I am trading my taco in on a ford with a 6.7 litre turbodiesel. Tired of getting 16 mpg and driving a slug as far as power goes. The ford has 390 hp and 735 ft/lbs torque. And will get near 24 mpg doing it. If I put a supercharger in my taco (thought seriously about doing that) I would spend $4000 which I would not get back in resale (on top of everything else I have done to the truck to make it right) and then would have to burn premium gas which costs the same as diesel and still would not be able to tow over 6500 with it. What's the point? Good money after bad.

 

The new 6.7 Powerstrokes claims are untrue. Even with the DPF removed the Dyno showed a RWHP 267HP and 615 ft lb of torque. This engine is a disappointment, the 6.4 Powerstroke had more power with a DPF delete alone.

Heres the video.
http://www.youtube.com/watch?v=iBiw3cW5ImM&feature=related

 

No the power of gasoline does not change, it still produces the same BTU's of heat. The only difference is the fuel is more stable as as the octane increases.

 

Track your fuel MPG with Fuelly! It's easy and I've got a better idea what my own MPG is compared to other Taco's out there! It's also a lot more consistent then listening to all this jabbering we all do........including my own jabbering!

See how most Taco's do---->http://www.fuelly.com/car/toyota/tacoma

 

I hand calculate my own and its pretty accurate.

 

You aren't going to notice any difference. Higher ratings are for high performance engines that are higher compression...... It does make difference in some knock issues, but you really wont notice anything....

 

haha me too !!

 

Correct in most cases but running too high of octain will cause runability issues too. The ecu can only add so much timing without a reflashing a new map.

Also, Ethanol will also keep knock counts down but leaves more deposits in your fuel system.... damn it... I sound like a commercial haha

Does anyone know of the actual hp differnces between 87 & 93?

 

Yeah im liking shell too, i used to use that typical grocery store gasoline (HEB for me) for over a year, and about a month ago i switched to regular shell. And i drive with a lead foot and i noticed my gas needle didnt go down as fast. Im happy with shell. And thanks to that grocery store ,HEB being right across the street, shell is always more or less the same price as them (usually a .01 or .02 cents in difference). Competition ftw

 

sunoco 87 = about 20 mpg. proof in the pic

 

straight from the QT website

i still run 89+ in my truck at all times

 

Fixed that for you.

 

yes and no, def driving habits, but dif companies, which have gas provided from different refineries = dif mpg , my opinion is due to dif levels or dirt and particulates in the gas....nj has some of cheapest gas in country due to the ports here get them delivered and travels a lot less. Hess for exmple has storage tanks all over the hudson river.... but i seem to get best mpg albeit slightly better, from sunoco vs other companies.

 

Difference in impurities/contaminants in the gas would be moot once the gas hits the fuel filter.

I'm willing to bet it's outside factors like your driving habits, the weather that day (which can make a big difference in mileage), tire pressure, etc. that widdle things around a bit. The differences aren't due to brand or octane.

The only reason I'm brand-picky about gas is detergent levels. Certain brands (top tier, BP, Texaco) have higher volumes than others when it comes to detergent.

 

ditto on better gas mileage with premium. I can typically go 20 more miles per tank.