Is there any performance benefits in running high octane, 100 octane or greater, gasoline in a MC? Back in the dirt track days of my youth a lot of the local drivers would run with 120 octane avgas because of the belief that the higher the octane, the greater the power, but I have never seen any “official” performance comparison with respect to octane rating.

And, if 100 octane gas would give more power than 91, will adding off-the-shelf octane boosters to 91 octane give you the same performance as buying 100 octane gas?

 

Check out this link, cRASH. I did a search on octane, and found that link in an old thread. Hope it helps.

 

You can read through the long and horrible thread - you can also go over to the MTH forum - https://www.northamericanmotoring.co...ad.php?t=71241

The good DR. posted a couple of graphs that presented information about knock and timming.
It won't hurt anything but your pocket book, but it *might* help ?

 

Put it this way. If you don't need higher octane, don't use it. You'll burn the valves in your car.

Regular gas actually produces more power.

 

cars without a knock sensor get no benefit from any higher octane than needed to supress pinging.

Cars with a knock sensor can gain benefit, but it depends on ECU tunes as to how much benefit, and how high an octane you need to get it.

FWIW, I have seen data that shows that a stock MCS will benefit from higher octane. Any car running a pulley surely gain benefit. STock MCs have been reported to do some timing retard as well, even though they aren't supercharged (But remember, they run higher compression ratios) but I don't have the data.

I bet the old racers put in the 120 and then advanced the timing to get more power.....

So, if you run regular in your car, you will get less power. But more interesting is that when the timing is pulled, you get less efficient burning as well! So I don't think you'll save any $, and it may actually cost more to run regular!

As far as what octane to run, I haven't done the testing but in talking to people, seems that 94-96 is a good range....

And no, the octane in a bottle isn't a good way to go. They don't raise the octane that much, and are very expensive. You'll find that it's cheaper to run supreme, or a mix of supreme and race gas, than to always use the little bottles of additives....

Matt

 

Thanks. I never believed, skeptic that I am, that there was a correlation between octane and horsepower, but I started wondering if their might be advantages to higher octane after reading the “Understanding the ECU” article in MC2. The graph of “Ignition Timing vs Octane” (for a MCS) got me to wondering if the same might not be true for a MC.

 

Thanks. The doctor’s information agrees with what was presented in the “Understanding the ECU” article in MC2. And that make me believe that there could be some performance gains from upping the octane. Not because it generates more powerin itself, but because in is less prone to knock at WOT. (Ever heard the term WFO?)

 

What octane is required for a non S MC from the factory?

 

Octane boosters add only a little to the octane rating when using standard premium gas. 100 octane gas is alot better but more expensive. For the Base MC it isn't really worth it.

Since this is in the H-stock forum- note that for 2007, SCCA prohibits H-stock competitors from using any octane greater than standard premium gasoline, you cannot use race octane fuel and remain legal.

For track use you can use race fuel and can get a little benefit especially for the MCS, but it's likely to be small.

You're better off making sure you air filter is clean and tire pressures are adequate.

 

Does MC require 87 or 91+ from the factory?

 

the gas cap says to use "at least 91 or higher" 93 is what they recomend.

 

Your MINI (MC or MCS) will take any Octane gasoline from 87 on up. MINI recommends that you use 91 or up for best results and for the benefit of your engine in the long run.

You won't hurt anything quickly by running 87 octane if really needed. If you plan on keeping your MINI for more than 5 years then put in 91 octane or better. If you don't plan on keeping it then it doesn't really matter what octane you use. You can notice higher Octane gives your MINI better performance and better mpg usually.

 

i have run sunoco 100 octane in my MCS for the past 7,000 miles. it gets better fuel economy runs cooler makes more power (doesn't pull timing)
and if i have any lean issues in the top end this fuel is safer.
all pluses except the $6/gal cost.

 

to figure out how much more mileage you're getting? I never ran the good stuff for long enough to tell, but I think I was getting about 30 miles more a tank..... You have any idea on your car?

Matt