IMO If you put regular into your car, it might not actually save you gas $, because you actually need to apply more gas for regular driving compare to premium.

 

When driving a performance engine use performance fuel.

High Quality Engine = High Quality Fuel

 

Car designers provide fuel specifications for a reason. As most have said above, follow the manufacturer's recommendations. It's a small price to pay.

 

Okay, I'm feeling like an idiot now. I've been driving my MINI since July 2006 and didn't know this. I guess I didn't do a very good job of reading the owner's manual and my salesman never mentioned it (though he did a very thorough explanation of almost everything else in the car).

So, do I just convert to Premium gas now or is there something else I should do to avoid engine shock over the good stuff?

 

and you'll be fine.

Matt

 

No way anything less than 91 is going in mine.

 

I just love how my in-laws try and use the fact that i have to pay for premium gas against me... Like i'm completely off my rocker for buying such a car in the first place. And I never have a good comeback to them. They are point A to point B drivers and would never understand anyway..so I don't bother. Anyone else get this from folks?..... It's like they're so smart by thinking they are beating the system or something...and i've somehow didn't do my research - lol

 

It's generally not worth it to bait the in-laws, but I would just let them know that premium gas only costs about $10/month more than unleaded would, and that the extra cost for premium is almost insignificant when you look at the total operating costs (purchase price, insurance, maintenance, etcetera).

(The $10/month number is based on 15,000 miles per year, 25 MPG, and a twenty-cent difference between the cost of regular unleaded and premium). Your numbers may be slightly different, but $10/month is a nice round number, and it should at least be in the right ballpark.

 

Yeah, the same types of people don't understand my motorcycle riding, either.

Zip

 

What car do they drive and how much mileage do they get? THEN compare with your Mini and mileage...that might shut em up...or convert them to the Mini!!

 

but they won't buy them... It has to do with timing advance vs octane, and how much increase in mean cylinder pressures you can make. What it comes down to is that higher octane allows you to get more energy out per combustion cycle.

You can also show them (but this will take a bit of work) that the cost per mile doesn't change much (if at all) for the different gasses. Run premium in your car for a few tanks and log the total miles driven. Then do the same with regular. You'll find that the miles per tank is lower, just how much I don't know.....

But then you'll have the data to show that lower cost per gallon doesn't really mean lower cost per mile.

Matt

 

The argument against this will be you (whomever) should have bought a car that was designed to get the best mileage it can on regular gas. But those are usually Point-A-to-Point-B types - not my cuppa tea.

Zip

 

even these cars could get better milage with premium if tuned for it.

What this comes down to is the source of my general level of frustration on many fronts. Those that don't know, or understand, nor take the time to really understand the principles, will say "yeah, yeah, but you should get a car that runs on regular." That means they don't understand the combustion cycle or how a motor runs. If that's the case, then no explanation will suffice.

Matt

 

And that's why I don't even bother with them. I generally 'talk cars' with 'car people.'

Zip

 

I took my 03 MCS Works into the dealer today, I've been having that classic, starts - stalls - restarts and runs fine problem, and they wanted to check to see if I had the lastest and greatest software. They updated it, then told me that if I kept having the problem the solution was to run a tank of 87 thru it..............

Uh........... I tend to follow the manual which recommends 91, so I ask the SA if he's sure about that, and won't there be a dramatic drop off in performance. (It affects my Audi allroad with the twin turbo V-6 pretty substantially to run less than 91 in it) He says only if temp conditions and load cause it to ping, then it will drop the timing back momentarily, then set it back again when it stops pinging. While prepared to give them the benefit of the doubt, I think I'll follow my own experience and judgement and keep putting in 91. I can restart it if it stalls..............but it does make me wonder. My car is out of warranty, so they have no real exposure here, but the recommendation was supposed to have come from their senior MINI tech..........

 

What he said was true, but it's just trying to get the ECU into a different space.... I don't really see that it would do anything, but then again, it shouldn't be a problem. The timing adjustment is instant....

And you will loose lots of performance. But it will come back when you go to the premium....

Matt

 

Yeah, I'm not sure what switching to 87 will accomplish re: the start/stall/start problem, but I probably just won't mess with it,. The car runs great as it is, I can just restart it on the odd time that it stalls............

 

In the uk standard unleaded is around 95 octane and super unleaded is
99 octane.(shell uk)
And when it comes to fuel costs,standard unleaded is around 95pence a litre and super unleaded is almost £1 a litre .
Thats with a exchange rate of $1.98 to £1.

 

I put in 6 gallons of 104 Octane to try to diagnose a potential detonation issue I've been having with the engine under load at WOT. Seems to have greatly improved the situation. With the AC on coldest and max power, I used to be able to replicate the hesitation pretty easily. At times, the SES light would go on during these conditions.

After the 104 racing fuel, the problem seems to be gone. With the load off, I could detect minor variations under WOT that seemed to indicate the problem was still there, but greatly reduced.

 

sounds like you either have some intake leaks or carbon build up. Try the Sea Foam first (easier to do) and then go from there.....

Matt

 

Interesting--after talking to 4 different mechanics/engine specialists, I've gotten 3 different recommendations.

I've never heard of Sea Foam
http://www.seafoamsales.com/motorTuneUpTechGas.htm

But it sounds interesting. Thanks!

Richard

 

but did some reading on the web, and when I bought it an old grey haired car guy called it "the miracle tune-up". There are some threads on it here. Search around!

Matt

ps, the cloud of smoke that comes out when you burn the stuff off is something to see!

 

https://www.northamericanmotoring.co...light=Sea+Foam

Matt

 

I posted a couple of days ago that my son put 89 octane in my R56 that has 350 miles. I have driven this tank (aprox 1/4 so far) and I haven't noticed anything yet. Just a mistake and intend to use the higher octane when the tank is done.

 

This is one of my all time favorite topics. Before I became a pilot, I was a mechanic. I am ASE ceritfied and Ford/GM school trained so I have a little bit of training to back up what I say.

In a nutshell:
-a typical car will make more power and get better economy with the LOWEST safe octane gas
-higher octane gas in NOT more volatile, it is in fact LESS volatile (higher flash point)
-higher octane gas IS required in performance engines where higher compression ratios/boost/nitrous raise the possibility of detonation (preignition due to combustion chamber heat lighting off the fuel mixture before the spark plug fires)
-high performance engines WILL lose power and economy with lower octane gas IF it causes the computer (via knock sensors) to retard timing, raise a/f ratio, and backing off boost
-if my minivan runs safely on 87, there is no point in using 93 and the detergants are typically the same for all grades of the better fuel brands

I will only use 93 in my MINI, but my Ford Windstar will never get anything but 87 unless it starts to ping (preignition). Until I did a great deal of research on this subject, I have to admit that I too was fooled into thinking that I would make more power from higher octane and that's the way the oil companies like it.

Cody