Originally Posted by LQQK

If, I do half tank with 87 and half with 91 does the octane become 89 or is it more involved than just averaging the #s?

Originally Posted by P0 Corsa

Thanks for looking Dan. I would think for advertising rights, Ford would quote the 444hp Boss output with premium (91+) fuel. But I am just guessing. I would be interested in hearing from any program internal forum participant(s) if the engine sensors (be they knock, O2, F/A, etc) can advance engine timing to capitalize on the 93 octane (vs 91) fuel some states (like the Midwest) still market.



Rick, I believe the answer is yes and I am not sure how long the engine manufacturers have had confidence to rely on the sensors to protect their engines from detonation. Quite a costly warranty risk if the sensor fails to protect.



I'll remember that. Although I'm not scared of that cipher pigeon he keeps using for his posts.....



Harley, I believe you are correct on both counts. Use 91+ for spirited/track driving and filling half and half probably does homogenize out to about 89. Back in leaded fuel days you could have probably gone with 25% premium and 75% regular. The TEL even in small concentrations quickly impacted the fuels octane rating. As posted earlier, if you can get non-alcohol blended fuel, that would be best from an energy-density point of view.

Originally Posted by cloud9

Unfortunately no knock sensors on the 07-09 GT500s.

Originally Posted by LQQK

So, 87 is good for everyday driving and 91 or 91+ would be the way to go for spirited driving??

If, I do half tank with 87 and half with 91 does the octane become 89 or is it more involved than just averaging the #s?

Originally Posted by 2012YellowBoss

That is insane, I thought eveything had one these days

87 would be fine if you are using it as a DD, there is nothing wrong with 87 like a lot of people think. "Super" is not cleaner and "regular" will not clog up your injectors or anything like this or other myths out there. When oil companies say higher octane is better for your car when the car calls for 87 is like tobacco companies saying smoking is actually good for your health.

Even though the Boss manual on second printing is calling for 87, it does state use higher octane on track and with the red key tune.

Back in the day mixing octanes would give you exactly what you asked, in fact stations like Sunoco did exactly that. they have two tanks and mix the gas depending on what you select. The problem today is the ethanol, it does not mix as well as they want to think so you may not get the exact results. I only drive the Boss for fun and use the higher octane, for everything else I use 87.

Originally Posted by Everett

That may be true for America however here in Canada supreme is pure gasoline without the ethanol pollution added to it. My car runs far better on it than any other fuel. Chevron and shell seem to perform best.

Originally Posted by askjeffro

Ethanol in gas is such a scam perpetuated by corn lobbyists and moron politicians. Every time it comes up it makes my blood boil. I'm leaving my statement at that to keep myself from going on a rant, but I had to say something.