false for sure

 

false. at some costcos they are now using a new type of detergent! i do not believe all costco have started using it but they all will eventually. the costco is oakbrook is the first costco in illinois to use the new detergent stuff. ive been puttin in my ride and have had no problems. my buddys with built up scoobies even run costco gas in their gas.

 

I would argue that not all 93 is the same. Octane in the US is derived by (R+M)/2, which means combining the research and motor octane values and dividing by two. But your engine's performance relies higher on motor octane. Ideally, using gas that has the highest motor octane content would produce the best results. Unfortunately, there is no way to determine this other than testing.

Personally, I don't put a lot of stock in Top Tier gas, and agree it's more of a branding and marketing thing.

What I do really care about is watching the activity of the station and how often they are turning over their tanks. This is especially true since we are rare and run premium, while 85% of the rest of the world is running 87. I think using a station that has a lot of customers and very busy pumps is probably the best way to go.

To that end, I use Kroger (local grocery chain). They have a deal where you get 10 cents off with every $100 spent at the grocery, and it works like a champ. They are always crazy-busy. My car was tuned off that gas, and I run it all the time.

All that said, the thing that matters most is running Tephra mods (and donating appropriately) so you have a knock light. If you get a bad batch of gas, you'll be alerted to it very quickly, and you could save your engine from such a small investment.

 

Agreed x2.

 

here in the Seattle area, all the gas comes from the same tank, the delivery driver adds a packet to his tanker when he fills it up at the storage facility. That packet is what makes it shell or 76 or exxon or whatever.

Lastly a local garage owner (30 years) who does a radio show and has friends in the refinery/gas business here in the Northwest... pleads with people to use Top Tier gas only.
His argument is that the detergents are crucial to keeping your injectors clean. Sure you can run discount gas for the life of your car but you are loosing power & fouling your injectors over the course of time. Alternatively you could use the cheap gas and add gas supplements but that costs more.

If costco is using gas with detergents then great, Safeway doesn't, 7/11 doesn't...

 

false unless proven ...

 

In New Zealand a lot of our grocery stores sell fuel and offer discounts if you buy your groceries there too. The fuel is usually slightly (2 or 3 cents per litre) cheaper to begin with too.

The petrol is sourced from the bigger petrol companies. The store I work at receives it's petrol from BP and is exactly the same as the stuff you buy from BP fuel stations, just not as expensive. I wouldn't hesitate to buy this fuel if they had the octane I needed.

Do Costco/Sam's etc not do their fuel the same way?

 

yes and no

 

I would assume it is the same, when you look up at former post about additives. Locally, you can use your Kroger plus discount at Shell as well, so I assume that is who sources their fuel.

 

i work at costco and we are in the top 5 best places to get gas. we add the most additives in our gas it burns cleaner and longer, and wont mess anything up. trust me i've been filling up my evo's there for many years.

 

What about Sam's Club?

I haven't tried their stuff out (since the closest one to me negates the savings due to its distance unless I'm already there shopping), but I remember when I was there with my girlfriend in her car, we did see a new Porsche there too.

 

I've been using Costco gas and never had a problem with it. How about Safeway gas? I've tried it, it seems ok but Costco is way cheaper that's why I fill up there

 

My Evo IX and STi always got better gas mileage and felt like they ran better on Shell and Chevron. Safeway/Costco/etc. etc. was the opposite. But that's just my anecdotal feeling, YMMV.

- Patrick

 

My car seems to run smoother when i fill up with Chevron and it's always the busiest gas station from where i am. Even though it's right across Shell and Petro Canada.

 

My EVO seems to gain more power using shell V 93, I heard they add some to the gas so its works like 94. As I know, my friend is driving a GTR and shell 93 works more significant. There isnt much difference if its 93 only could be performance difference, it wont ruin ur engine.