"For full power"

New GMG 6.2 gas engine comes with the instructions “preminum required for full power” This somewhat of a wrinkle in the “either preminum is recommended or it is required” instructions from the manufacture.

I guess you can use regular if you don’t plan on using full throttle.

To me that means regular is OK as long as you accept less power and performance from the motor. It actually sounds like someone took English 301 and is reviewing the owner’s manual and making some sense for a change.

This will give those “wise” people an excuse to use low octane fuel (such as kerosene): “I’m never going to use full throttle to get onto the freeway. Nah, not ME.” Yeah! Right!

Sounds exactly right - if you want max hp, use premium, lets the engine run max advance. Use regular and you won’t get quite as many hp. I recently saw a test on the a new Ford engine, they gave hp for regular and premium, made a few hp difference.

I like it…maybe we could have a tank of each and only inject prem. when that full power is needed, like a little nitro.

Ford’s working on an engine that does something like that with ethanol, run the turbo at full boost if your using E85, partial/no boost if you’re not, with a high (11:1?) compression ratio.

I like nitrous oxide for that use…at least you can laugh at your self it it doesn’t work.

What I pulled from the review (USA Today,today business section) was it is made clear, no engine or emission component damage, guaranteed.

Few people will be able to detect any difference in power output…

If Ford wants to promote the E-85 movement, they only need to offer a 14 to 1 compression E-85 ONLY engine. That way you get the benefit ALL THE TIME, not just at full throttle. The average driver uses “Full Throttle” less than 1% of the time…

All that means is that if you want to get the advertised amount of power out of the engine you’ll need to use premium. The engine will run fine on 87 octane but you’ll be giving up some power. The ECU of the engine has a dual knock strategy built into. The new 5.0L DOHC Ford V8 that’s going into the 2011 Mustang GT is similar, it’s rated at 412 HP when running on 91 octane and a bit less than 400 HP when running on 87 octane.

That sounds like a better wording that the usual premium recommended, without telling you why. Likely it will also cost you a little mileage if you use regular.

I don’t think using full throttle or not is a problem.

The engine will likely put out less power over the entire power curve or maybe part of it.

My friends recent VW GTI with a nice turbo engine allows for the same thing. He states the difference is not very noticable. Although he seems to get slightly better MPG using premium instead of regular.

The truth is even in my high sprung turbo WRX I don’t notice a huge difference in regular when used(can’t find premium in the sticks sometimes). However go into boost and especially with AC running and hot temps I notice a real difference.

Relying on an imperfect memory, it seems to me when my 2002 Sienna was still fairly new, Tom and Ray discussed this very issue, and (again by memory) said one gets a tiny bit better mileage on motors recommended for premium if you use premium.

At the time, I discovered as closely as one can tell driving a lot on the highway, around 2 mpg improvement with mid-grade over regular, over a long period of time. Since I am in Mexico now, I don’t know current prices, but at that time, the difference between the two grades of gasoline was small enough there was no added cost to using the better gas.

I am aware that using fill-up pump measurements can be somewhat imprecise, but as a matter of personal preference chose to go ahead and act on my own measurements, aware the difference, even if I were wrong, would not break me.