I've heard this around, but not sure how true it is. Any thoughts?

I've heard that when I go to a gas station that only uses one pump for all 3 grades of gas that, when I put premium in my MINI, I am more than likely putting in a good bit of "regular" gas along with it. This is because the person that filled up in front of me was probably 99% likely to have put regular grade gas in their car, therefore I get the entire pump hose full of regular before the pump starts dispensing premium.

Now, I'm certainly not worried about this harming my MINI. I've read the debates back and forth about gas grades and what to use. Even if I did get a good portion of a tank of "cheap" gas, the minimum octane rating for my MINI is 91, and I think premium is 92 or 93, so even if it was diluted so to speak by regular grade gas, it wouldn't be by much.

But heck, if I'm paying these prices for premium grade gasoline, I want to receive it! So I'm thinking about keeping an eye out on my daily commute for a gas station that still has an individual pump for each grade of gas. I wouldn't go out of my way to do it, but I might change my gas station of habit.

Anyone have any idea if this is true, and how much gas is in the pump? I can't imagine it's more than a gallon, so I won't penny pinch over 20¢, but just curious...

 

Yes, probably true. But, the amount is so small relative to how much you buy as to be trivial.

 

Gas spoils. with that said, the pump that has 3 individual pumps could
have expired gas in the tubing before you get the fresh gas... especially
going by the idea that the person before you used regular gas and
smaller population using premium gas.

I rather have a little bit of new regular gas than old spoiled premium gas...
but honestly, I really don't care which pump type I use.

 

BMW motorcycles, specifically, K1100RS. they came to the conclusion that for a bike tank. like a 4 or 5 gallon tank, it was minor. someone who knew something about gas pumps thought you might have to pump up to a gallon of "existing" gas in the hose to get to the super in the piping to the super tank.

i try to use pumps that are dedicated to each grade.

keeping your car waxed (and cleaned) is also supposed to generate up to 7% better fuel mileage according to the news rag today. don't know if i belive 7% though, but it gives you a good excuse to wash your car!

 

No kidding! I never thought of gas spoiling. I know the amount of non-premium I would receive would be (I hope) minimal, if I didn't have to go out of my way I was thinking of finding a multiple hose gas station.

I can see how this could be a major issue with performance motorcycles since they have much smaller gas tanks.

I guess if we were really receiving more than a gallon or so of non-premium gas that 20/20 or Dateline or one of those shows would have already done an expose on it by now!

 

In here most of the gas station provide with 93 for permium gas.. I bet 0.01 gal or less of 87 gas inside the tube won't bring my premium gas down below 91 rating...

 

yeh, the reason why most people don't over purchase 100 octane gas
in their portable gas containers to mix when they get to the track.

So most people buy 'just enough' for their track day. :smile: