I wasn't aware of that 0.o

I only use Shell, 93 Vpower ( Been using it for years 15+) Will if need be use Sunoco but and always use the same station -if I can-.. The octane booster the only on I used is Turbo 108
Blue Magic/16 oz. Turbo 108 Octane Boost NA30 at AutoZone.com

I have no way of testing it other the a years ago I did my own thing with my old Monte SS. I hadn't started using this stuff yet, I took the intake mani off and changed it and the carb, notice a lot of yellow deposits and build up inside the carb and intake runners. I ran this octane boost for 8 weeks took of the carb and mani again and could eat off it.

I use Shell, Valero, Chevron/Texaco and now Murphys (by Walmart) with no issues with any of them. I dont care where I go and I buy the cheapest I can find.

I think another member on here (BGTV8?) originally posted this, but FWIW, here are some independent lab test results on changes in octane from various additives. I'll see if I can find something more authoritative, but for now, this is seemingly impartial and informative.

Note that they are going by RON, not AKI (RON+MON/2). TO get an approximate, multiply the RON by .95 (e.g., 96 RON is approximately 91 AKI).

http://www.fueltechexperts.com/2008/...which-is-best/

:iagree: Every 4th or 5th tank I put in Chevron premium (I'm a believer in Techroline for keeping the injectors clean).

Lower Octanes
 

Lower Octanes are used in higher elevations, because of the thinner air. Something to do with the fuel/oxygen ratio. I read this on Shell's site, after being use to 93 octane here is se texas, then being able to get only 91 in the mountains.

The lower air pressure as you start climbing several 1000' above sea level reduces internal temps and also effective ("dynamic", I think...) compression, so less likely to autoignite the fuel.

Go up high enough, and the lower oxygen levels also mean you need less fuel to hit AFR/Lambda targets.

Of course, you also lose power.

Octane is just one of the many factors that helps control unintended combustion events (reflects resistance to "auto-ignition"), which result in knock (the sound made from an un-timed combustion event).

The force from untimed combustion events can break pistons (ring lands in particular tend to be weak points -- enough force produced on a timed even can do that too, BTW), break loose rods from their bearings (i.e., "spinning a rod"), or if you have a high enough temp produced from a flame kernel on the piston crown, it will look like someone took a welding torch to it and just melted through the center of the crown (google it -- it's kind of horrifying! Much nastier looking than a shattered piston.)

Extra fuel (i.e., "running rich") also helps cool down the piston -- that extra fuel is "wasted" to quench hot spots.

What causes fuel to ignite out of time (i.e., not during a planned spark event)? Too much in-cylinder heat (mitigated somewhat via clever valve timing or freer flowing head and EM as well as lowered intake valve temps -- that's part of why intercoolers or W/I is great on boosted engines), higher cylinder pressure, flame kernels that don't disperse quickly enough for various reasons (e.g., "hotspots" on the piston crown), uhh... I'm sure I'm forgetting something, but that's the gist of it, at least based on my modest understanding of engine tuning...

Me too. I buy when I need to and at whichever gas station is open. Did that and put up 156k miles on my Prelude, never had any problems with it, my 350Z and any other car I drove.

Putting select gasoline and thinking your car drives better for it is like buying the most expensive golf clubs and thinking your golf game will be like Tiger Woods.

It's why "branding" works. It falsely convinces people that buying their product makes you better.

BINGO!!!!!!!!! :iagree:

The only gas I will never buy is Arco. I purchased it once back when I had my SRT4 and my car ran like **** for the entire tank of that watered down POS. It could have been that particular gas station (and it was when gas was really expensive and ARCO is almost always $1.00 cheaper than any other station) - so the sheer volume could have contributed to its shittiness. Thankfully you don't see too many Arco's around here in Phoenix.

QT & Fry's are where I typically fill up. Fry's has gas points that I steal from my parents. :icon17:

If I see a tanker filling at the gas station I was told to go elsewhere. It is bringing up the settled particles in the tank and takes awhile for homeostasis. you don't want it in your car.

I get better mileage and better performance with Mobil, Chevron, Shell, and 76; all other gas stations are cheaper but in the end it end up being more expensive as mileage drops with cheaper gas and performance is lower. Of course this is my experience and my opinion and to each their own, but I never put cheap gas in a car I own, especially a performance car.

As far as I can tell, there's little difference between brands of gas. The condition of the tanks at the station can make a big difference. YMMV

Length of gas stagnation/quality of tanks simply never even crossed my mind...before my 370 I was a devoted Jeep guy and the last worry on my mind was quality of fuel in the engine given that I Seafoam and change the synth ever 3,000 miles (just how I do, don't care about cost issues and the 3,000 mile myth.) I was simply astounded by my Z's engine acting as though it had caught the schoolyard sickness after one sip of the Kroger fuel...I'm definitely grateful to everyone's comments regarding fuel and I think that in a seeming land of zero consensus there is one grand consensus: we'll all stick with what works for us - for me, that's Shell V-Power and will be until my car itself tells me otherwise.

I worked at a BP in college and before (6 years) and know that we were getting the same gas delivery as the stations around us, including an off brand gas station down the road. Also, the gas station having a newer underground tank is huge. Gas stations are allowed to have a certain amount of water in there tanks (it happens) and the older the tank, more water. The owner is supposed to clean the tanks often but that is expensive and I know some owners will not. How full the actual underground tank is with gasoline is a big thing as well. If you are the unlucky person who gets the gas when the gas stations tank is low and needs to be filled, you may get some water as well. There are too many factors. Each pump also has a fuel filter that needs to be changed often and can damage cars if they are not changed. You can tell the fuel filter is old in the pump if that pump is going very slow. If all of the pumps are pumping slow then the station is low on gas. I would suggest looking at stations that are just well kept.