I usually run a mix of gas in my '06 MCS - generally 3-4 tanks of regular followed by a tank of Premium. If the prices fluctuate down, I'll put in the middle grade for giggles, but I know all too well that with summer comes higher gas prices. Since I don't thrash the car, I've experienced no pre-ignition issues or any other problems with this regime so far, and it saves me money. If I know I'll be out with a MINI group driving hard, I only put in Premium.

Thing is... I'm installing a 15% reduction pulley later this month, and I'm wondering how the extra compression will affect me, given this gas regime? I don't want pinging. I know some people even add octane BOOSTERS with a pulley installed!

Do you think I can continue with my practice of using Premium every fifth tank as well as on high-rev days, or realistically am I looking at using "the good stuff" with every tank? It's only an extra few bucks a tank, but it adds up... Also, what about (no doubt pricey) octane boosters?

Thanks!

 

Well I always use the 93, kinda likee that book that came with the car said I was supposed to in order to keep the car running well. yeah the $$ adds up but its worth it when I get another 50k-100k out of the engine.

 

If you're going to spend the money on the pulley why not spend $3-5 more a tank and get full advantage of it.

 

I will never run anything but premium in my car. Mainly due to how hot the ic gets and engine in general gets even stock.

I would suggest to avoid timing retard and future knock/ping problems you do the same especially once you add a 15% pully. Boost will be higher and so will temps meaning you are putting yourself at far greater risks.

 

For the extra couple of dollars a tank, just go premium. Especially with the pulley! In our area, premium is $.20/gal more. Why take ANY risk for $2??
Can you really say that you won't need to stand on it when you go for the regular gas? You may not be hearing pinging, but that doesn't mean the car doesn't sense it and retard the timing/add fuel to eliminate it.

 

I think every MINI is a little different...outdoor temps can play a role as well...With mine in Phoenix, AZ, my car started pinging right after the 15% pulley install. There are a plethora of owners in AZ though that have 15-19% pulleys with factory software and have no problems whatsoever. To try to help, I tried the NGK Iridium plugs...no luck. Next I tried the JCW flash...no luck. Next, I started mixing in 100 octane with the 91 I was getting at Chevron or Shell (about 3 gallons per 12 gallon fill)...bingo...no more pinging, but, very expensive to fill up. The latest was the JCW injectors which seem to have solved the problem, plus my gas mileage has increased significantly. I no longer have to use the 100 octane (we'll see when the temps hit 110+). I would be willing to bet that you are currently sacrificing power by not using 91/93 octane and would lose even more with a pulley. I'd reccomend sticking with premium gas though even if you don't experience knocking. The knock sensors in most of our cars (maybe not mine?) do seem to work very well, but will rob you of power if detontation is detected. Good luck and have fun with the pulley!

 

I do not know this as fact so maybe someone else can shed light, but I believe all the cars have a knock sensor built in that automatically retards the timing when you need to, so you wouldn't hear any knocking, but the car would be making less HP when it needs to back off some. By going with a pulley you are going to force more air in, and ask the computer to do more work, that may be outside it's factory specs.

Personally I would love to see the carbon build up on your valves, I would bet if you opened up your engine you would never use regular ever again.

 

Since I got my pulley last summer, the only time I have ever put "plus" gas instead of "premium" was this last week and that was only due to the wild pricing fluctuations. While I have not noticed any pinging at all, I HAVE noticed a slight drop in gas mileage during mixed driving. I can see perhaps using "plus" every now and then...perhaps when I plan to be driving mostly flat roads or interstates. However, for performance or mountain driving with twisties and long uphill grades, "premium" will be the ONLY gas in my tank.

 

Personally I can't believe you guys put regular gas in there. The difference between regular and premium in most places will run you $2.80 or $3.00 more per FULL fill up.

 

Someone did this calculation before, but I figured i'd do it again. This is assuming 20 mpg, 260 miles per fill up (using about 13 gallons a fill) and driving 20k miles per year (Average is between 12 and 15k)

Using these calculations you would need 76.9 fill ups per year of 13 gallons.

This is 999.7 gallons of fuel (For simplicity lets just use 1000).

I live in Southern California, which by FAR currently has the most expensive gas in the country.

Regular gas here is $3.15 a gallon, premium is $3.35

Total yearly gas cost of $3150 using regular gas, or $3350 using premium. So there's a $200 a year difference. So using this extreme example, and assuming that you get HORRIBLE gas mileage, that your mileage doesn't go down cause you're engine is retarding timing (Most people notice a 1-2 mpg difference between premium and regular) and all other things go completely fine. You will save a whopping $3.85 cents a week. Yes, 15 dollars a month.

For kicks, I ran this calculation as well. If your global MPG dropped by 2 (18 mpg) your yearly gas cost would skyrocket to $3500 a year. So in an effort to save 4 dollars a week, you not only will most likely use another 110 gallons of fuel during the course of the year, adding to the waste that is already taking place from all the gas guzzling SUV's out there, but you may actually spent $150 more than the same driver using premium fuel.

Skipping Starbucks once a week would yield more savings than skimping on gas that your manual says is REQUIRED for proper operation of the car.

Another way to look at it, you're about to spend 250 dollars to install a pulley so you can gain 14 HP only to put in gas that will lower the gains by 30-40% .


I’m 20 years old, and far from a millionaire, and I have no problem saving 3 dollars a week elsewhere (Or just paying it... it's 3 dollars) to allow my car to recognize its full potential.

Sorry if this seems bitchy in any way, I mean no offense to anyone, I’m just tired of seeing these "Omg I saved 3 dollars this week by switching to regular " threads.

 

I admit that on my recent 2K mile trip to AMVIV, I briefly contemplated not using premium "because I was on flat roads". Then I got over it. It may have cost me $12 or so for the whole trip. Hell, I paid more than that for the 'affiliate registration' for my wife. And I got more for it.


One positive of the increase in gas prices: The delta between premium and regular has stayed at $.20. That used to be a big percentage (13%) when the base cost was $1.50. At $3.20, it's a mere 6% premium.

 

I 100% agree with you but on this one point. Hawaii is a lot more expensive.

 

the car runs super rich regardless of what pulley you run. I have never tried running either of my Cooper S cars on anything less than 92. Although I knew a guy back in the day who ran his on 89 and did not have any problems.

 

I read somewhere that the Europeans use a different octane configuration for their gas.

When I was in Spain last Christmas, I stopped at the MINI/BMW dealership in Madrid and asked what gas they recommended for the MINI Cooper S, because they have other MINIs [MINI D, MINI One, MINI Cooper]. I was told to use "super" in the MCS, and "normal" in the MINI One and MINI Cooper]. Since the MINI D is a diesel, it uses "gas-oil".

 

Yeah normal gas over there STARTs @92 and goes up to 98 ish the non race stuff

 

Europe uses RON whereas we use (RON+MON)/2, so the numbers aren't directly comparable.

 

LOL... I knew I'd get a ton of "OMG - you use THAT gas?!?!?" replies, but I've also talked to a bunch of people running MCS's that use the same regime with no issues, so I thought I'd check anyway. I figured most answers would come down squarely in the "always use Premium!" camp, but thank you, rustboy for running the actual numbers - quite illuminating.

As for MPG, I don't really check mine - I'd say that 80% of my driving is on short (less than 5 mile) trips at fairly low RPMs alternating with long, easy 30 mile highway drives 1-2 times a week, so I just fill up whenever I get low and don't sweat the MPG so much. I was sort of looking for an excuse to get better gas anyway, and this looks like it's it. I'll hear about it from the missus (she tracks every penny) but hey, it's worth it.

I just hope I don't have problems with the 93 like SayGoodby had. Oh, and the vendor that's installing my pulley also installs the colder plugs along with it, so that should help as well.

Thanks!

 

Actually no... there have been many times over the last few years where CA has been higher than Hawaii...

Oct. 2004
http://www.bizjournals.com/pacific/s...8/daily11.html


There have been numerous broadcasts about the prices of gas in CA exceeding anywhere in the country over the past few weeks. Here's one from the 21st of March

http://newsbusters.org/node/11568
http://www.signonsandiego.com/news/r...-gasoline.html

CA currently leads the country in gas prices, this is the AAA website that monitors gas prices nationally

http://www.fuelgaugereport.com/sbsavg.asp

You can see while Hawaii has an average price of $3.21 for premium, we have an average price of $3.54 for premium .

On a positive note, all this great expense we go through for specialized formulations of gas and carb restrictions/octane limits have lowered the polution in CA by .0000000000009% in the last 25 years! Meanwhile, Sacramento is loving it, cause they get to write tickets and fines out the wazoo for the most mundane things imaginable

 

Colder plugs aren't needed. Stockers run just fine

 

check to make sure those plugs are torqued to 22ft/lbs every other gas fillup. You can read up about the magical flying sparkplugs on this forum through a search.

 

ImageX,
Since the difference between regular and premium gas is only the octane, putting in the occasional tank of premium doesn't really do anything special. I used to run on the mid grade before I got the pulley and had no performance or economy issues at all. After you get a pulley, try switching between mid grade and premium. If you don't notice any difference, stay at mid grade for most of your regular driving.

Remember, the octane rating measures the ability of the gas to resist igniting, not it's power. So as long as the engine doesn't have to adjust timing (economy and performance doesn't change), there is no effect on the engine itself.

 

Colder plugs help with pinging, but not that much.

The engine will retard timing before anything really happens, but it also uses more fuel by doing so (Negating any benefits of using the cheaper gas).

With gas at 3.35 a gallon, every mile you drive costs ~.17 cents. So if your MPG drops by more than 1, you've negated any benefit of lower gas costs. This obviously fluxuates with price, but if it's 2, it's still statistically insignifigant. Taking one less trip on the freeway could lower your global average by 2 easily :-\.

I like you drive 95% on surface streets (I avoid the CA freeways like the plague). I see about 21 MPG total driving enthusiastically.

I used to have a G35 .
20 gallon tank (18.5 gallon fill ups)
60 mile round trip commutes daily for work x5 + random driving not related to work...
15 mpg in our wonderful SoCaL traffic
$3.40 a gallon premium (at the time)

$400 a month for gas. I STILL used premium.

Regular gas is the devil! (What movie is that from? Where everything was the devil or a sin )

 

If they're torqued properly with some loctite the first time shouldn't they be fine? Maybe 3-4 times a year, but twice monthly seems like overkill . I remember reading the threads about this, scared the crap out of me, but it only happened to a few people, assumingly because they weren't torqued properly to begin with.

 

That's what I read, too on a few sites that spoke about octane and such. I alternated because there was an opinion that some of the higher octane products also contain additional detergents and such, however a recent peice I saw on the Today show compared several brands of gas and found that they're all basically the same (other than octane, of course). More marketing BS, I guess.

The difference between mid grade and premium is only about a buck and change per fill up - for that price I'll pay the extra and have one less thing to worry about. Thanks so much for the comment though!

Rustboy: I don't seem to be getting quite the MPGs as others report and timing retardation is likely the culprit - I'll try running a few tanks of Premium through Nano and see what happens - thanks again for running those numbers!

 

X2! A helicoil job would definitely dent the gas budget.
I think every 500 miles is a bit much, but definitely every couple of thousand.


edit: rustboy - loctite on spark plugs???!