cwazyeurodrivr

WOW huge huge difference I noticed after a 1/4 tank used already.

I'm usually good for 88-92-4 miles per 1/4 tank, I'm at 138 miles on sitting at 3/4. Nice work Shell!

TomF

Here in Seattle it will be more like Shell ho-hum 87+... We don't get good gas around here! It will also include the requisite 10%+ of ethanol.



Cheers,
TomF

cwazyeurodrivr

Damn tree huggers, Omaha and Socal is 91. My company has been hinting relocating me to San Diego area, so I wonder if the ECUs would need to be reprogrammed for the octane difference?

5thlilpiggy

There is a Holiday station in Bloomington here that has a pump with racing gas (100+ octane I believe).

I am tempted to try it, but it runs about $8-9/gal

cwazyeurodrivr

I ran it in my RS5 a few times when it ran like crap, wish it wasn't so expensive, I've put it in the Cayenne Turbo S twice now just to keep him clean, BUT was $170 to fill the tank from the " hey stupid, I need fuel" light on.

dasams

Is this new gasoline ethanol free? If so, you should see perhaps 2% mileage increase. Anything more is a placebo effect.

You P!g will run fine on 91 octane in CA.

mtnrat

We have a fair amount of 94 octane available with no ethanol. Here is where to find ethanol free gas for Canada and the US.
http://pure-gas.org/index.jsp?stateprov=BC

TomF

My buddy owns a station that is one of two in the area that has ethanol-free gas. All the lawn-service companies fill up there to save the gaskets on their power tools.

I live just down the beach from Kenmore Air Harbor, so I can get aviation fuel if I really want it!

Cheers,
TomF

wrinkledpants

Pretty sure it's just rebranded V-power. The base fuel is all the same with the octane/additive pack being added at the farm. Premium and Regular are mixed at the pump for the mid-grade octane, and since there are often various octane levels for the mid-grade it would be tough to ensure that the fuel is properly mixed if premium were substantially different.

I've never paid attention to where I get my gas. Every car I've owned has gone over 200K miles without any buildup in the heads. Never replaced an injector, either. Recently, most of my fuel has come from grocery stores.

Even in the aviation world - nobody cares what brand of fuel they use, and those motors are running at 80-100% power all the time with rebuilds typically costing 30-50K.

Corso

I'm with you on that. If the car needs gas, I pull over at the next gas station and get gas. The end. Never once have I had any concern regarding whether the fuel was of adequate quality or not. Octane requirements adhered to, yes, brand, no.

Gofishracing

Be careful what cars you put that fuel in.

cwazyeurodrivr

I put on more miles in a week , than more Porsche drivers do in a month sometimes. I have noticed a huge difference between using different brand fuels. Keep in mind , I'm averaging 218 miles a day ( Monday to Friday) so far this month.

My personal ratings by brand

1: Shell : excellent response , more mpgs
2: Irving : good response , good mpgs
3: gulf : good response , avg mpgs
4: bp: avg response , bad mpgs
5: mobil/Exxon : avg response , noticed more fuel injector noise , warmer temp days rough idle.
6: citgo : sluggish response , had to double check the mpgs was too good to be true. Avg 25.9 mpg on a tank.


Every fill up it gets 93 octane , every 20-25 tanks if I'm near the raceway I'll go to the gas station near the race track and fill up with racing fuel with at $7.50-8.50/gallon and clean out everything. The master tech at my local dealer suggested it to me because he races on the weekends and says would be best with the miles I do.

He laughs when he sees me for service and said he's taking bets on how many miles I have on it in 1 year. It will be going in for its 3rd 7500 mile oil change soon. No problems to report, rock solid and extremely happy with my fuel addicted speed demon.

Sent from my iPhone using Rennlist

wrinkledpants

You're not cleaning out anything with race gas. Your car can't advance timing enough to use 100 octane, and it's resistant to detonate also changes the burn pattern the gas has during closed loop (part throttle). This is why people will have a switchable ECU with a 91/93 octane, and 100 octane. Or, they have two different ECU's.

Pulse width, timing, ignition - this is all premised on the fuel mixture igniting and burning for a very specific time to ensure that the most force from the burn is timed at a very specific crank angle. Your car will pull timing if you run 87 octane, and will likely cut throttle when it can't pull timing anymore. Even though the CTT will pull timing, it's fueling maps still aren't optimized for 87 octane, which is why you end up with worse mpg.

Octane isn't like cocaine - the more the merrier. It's high resistance to detonation also makes it highly resistant to igniting, and will have a different burn patter. Most OEMs that spec 91 will put a bit of headroom for 93, but I would not be putting 100 octane in a car with a factory ECU. You have a direct injection motor, not port injection like the 955. Fuel isn't hitting you valves - so I'm not entirely sure what you think you're cleaning. The only reason you would have any kind of buildup is from a poorly functioning motor, or running the wrong octane of fuel.

cwazyeurodrivr

According to the tech , buildup can still happen on the fuel injectors, exhaust valves & exhaust chambers. I'm just going by their recommendations. Mine might be old enough to really notice the difference but I'd rather be proactive than reactive.

Sent from my iPhone using Rennlist

Corso

I've been averaging 40k/mi/yr since '99 (traveling territory mngr). Been through lots of cars and lots of fuel. Never have I experienced such a phenomenon. Not saying it may not exist, just my personal experience.