I was speaking to an acquaintance of mine who works for GM in the Engine Design dept, he basically helps design new engines. He's told me in the past that you should basically use the octane that doesn't make your car knock and ping. If you notice your car not performing as well, then step up a notch. If that means going from 'regular' to 'medium', cool deal. If your car runs fine on 87, great.

He also eluded to the reason behind the "only use 91 in this vehicle" is that the car companies are 'in-cahoots' with the oil companies trying to convince you to get the highest grade gas because that's the highest profit margin for them.

Anyhow, has anyone experimented with different grades and have you noticed any performance differences?

 

I'm new with a 07 MCS from what I have read hear it's good to us premium. Here is a thread to read about it. Hope that helps.
https://www.northamericanmotoring.co...ht=Premium+gas

 

thanks for the link... will read through that one

I'm really curious to see the MPG difference. Here in so-cal, where premium is over $3.50 a gallon, I need to see what the overall cost difference is

 

MINI has designed the engine to work with 91 octane, which is why they recommend that that's what you put into it. Think of them as already having done the "Try a lower octane" experiment so you don't have to do it

 

Just read a post on MINI2 in which the writer said that the I believe I've given a link to this on another thread here on NAM about MPGs, for what that's worth to you here it is http://www.mini2.com/forum/mini-club...ml#post3360598

 

Coldfrye-
You may want to search the other discussions on this board, as this topic has been covered many times before. Your friend's conspiracy theory is laughable. MINI recommends premium, so I use premium. All MINIs have high-compression engines, which benefit from higher octane fuel (aka premium fuel). The engine will run on lower octane fuels, but that's not what it was designed for. Octane rating is essentially a rating of resistance to pre-detonation of the fuel under compression. The higher the octane rating, the less likely the fuel is to pre-detonate when compressed. Engine knock is the sound made when the fuel ignites before the spark plug fires, owing to too low an octane rating. Again, you can use anything you want, but premium will provide the optimum operation of your engine, which is why MINI strongly recommends premium.

 

If you pay $25K-$30K + for a new car, why go cheap on the gas? To me the great gas mileage afforded by the MINI, more than compensates the added expense of premium fuel.

In cases where 91-93 octane is not available, the car can run on either 87 or mid grade 89 gas as the computer automatically adjusts for the octane difference.

But don't make it a habit of filling up with regular, just to save "a few pennies". That is called a "False Economy" because later in the car's life your engine may not come to appreciate a cheap diet.

If your goal is to save gas, keep an eye on tire pressures, consolidate trips, Go easy on the gas pedal, avoid harsh braking,try to get a job as close to home as possible, maintain the vehicle as per manufacturer's specifications, etc.

 

"Premium recommended" is a good trick (we use it). It means the vehicle will run with 87, because knock sensors, etc, catch it before you even feel it and retard or advance ignition, etc. To get the advertised hp, however, you have to run premium. The up-side is that people are more apt to buy cars that will run regular (especially now!). But running premium will always allow you to get the most out of your car.

 

so the best bet is to run midgrade 89 or in Sunoco's case 91 and get the best of both worlds.

I really doubt that if the MINI "required" premium it would be such a big hit in the rest of the world, where gas is even more expensive. Willing to bet that most Europeans use regular in it.

 

It's that time of year again... seems like more of these threads are popping up this spring than last the last .

For the record, you can run a 911 Turbo on Regular gas... Sure, you'll lose 75 HP from retarded ignition timing, but it'll run fine. Modern engines can run on ANYTHING. Will they run well? No... The MINI as it is runs with the ignition timing dialed way back even on 91 or 93. To make it even worse by putting shitty gas in is just silly.

I guess to some people $41 for a full tank is always less than $44 a month, even if it means they have to go to the gas station 60 times a year instead of 55 .

 

thanks for the feedback, folks. I really appreciate it.

(Prolly gonna pull the trigger on a ClubMan-S this weekend. Then wait the 8-14 weeks)

 

mid-grade is a crap shoot. it's a mixture between high and low grade and not always 50/50. you're better off going with one or the other so you at least know what you are doing.

 

Where or where? All the spots near us now are a minimum of $3.85 and most at $3.99 or even over $4. The only bonus is driving the Mini and getting some good mileage.