elcheapo

just like the title, does it matter which one chooses?

strangely enough, i used to always fuel with shell 91 vpower as i heard that it doesnt have any ethanol (at least not where i live). i almost ran out one time in a long trip this week and had no choice but to fuel up with sunoco 94 (with up to 10% ethanol, accdg to the specs). strangely enough, sunoco 94 "seemed" to have better fuel economy. maybe it's just bec it's a "summer blend"?

which one to choose? do you guys mix and match the whole time? are all of these horsesh!t ?

btw, i read in the manual you shld fuel up with at least 91 (hence sunoco 94 has more "margin of safety) but no more than 10% ethanol (here shell has more "margin of safety" with 0%? ethanol)...

mau108

Shell VPower is what I use the RDX and the Prelude as I find it gets better mpg and drives better.

Last time I filled up the RDX with Petro Can 94 (Sunoco 94), RDX just didn't feel right.

elcheapo

thanks mau. read somewhere that check emissions light flares up once in a while w/sunoco 94 (in fact it might be your post - but i also read you were good with sunoco in some other ). 91 vpower at 0% ethanol FTW then , but sunoco 94 will be a 2nd (and last option)... will definitely avoid esso, canadian tire, petrocan LOL.

mau108

yup, I'm a Sopus promoter lol. I use Shell fuel and use Pennzoil oil!

mrgold35

Consider yourself lucky to have a choice between 91 or 94 octane. We only get 91 in the "Big City" and 90 in the smaller towns (where my in-laws live).

I would use 94 octane with my RDX+reflash.

Do those octane booster work? I have to fill up with +15 gallons of 90 octane when I leave from visiting the in-laws. I don't know if it is worth spending +$5 per bottle or just tuff it out until I fill up again with 91.

mau108

Try one of these stations ?

http://pure-gas.org/index.jsp?stateprov=NM

Albuquerque eh, I watch that show In Plain Sight and it's based in that city.

MMike1981

...i too will concur; best MPG w/shell V-power, i usually get about 20-30 more miles per fill compared to Hess (@93 grade)

brizey

Most of the time I use QuickTrip--they are the closest Top Tier to my house.

http://www.toptiergas.com/retailers.html

Ethanol at 10% will not hurt your car. Even E85 might not if the computer and fuel injectors can keep up. Technically all the seals, etc. are designed for 10%, so theoretically you might get premature wear with more than 10%.

Ethanol is a superior performance fuel compared to gasoline. E85's octane equivalent is 100-105 so you can run a ton more boost. The fuel density is lower, so it takes more fuel to achieve equivalent A/F ratios. Hence you may need an upgraded fuel system to deliver it. In the WRX world there are lots of E85 tuned cars making crazy HP. It's like race gas you can buy at Kroger. Stock fuel system WRX's can run something like 25% E85, 75% E10.

brizey

Ran out of edit time:

Toluene is a great octane booster. It is already used by fuel companies to adjust octane levels. Many companies' unleaded race gas can be up to 25% toluene. And you can buy it at paint stores. Just google it. The late 80's crazy boost F1 cars used something like 90% toluene. I used to get 5 gallon containers at the commercial Sherwin Williams outlet (I had to sign up as a painting company to buy there, but it was way cheaper).

elcheapo

thanks for the replies guys.

here's a thought: i always fuel up with 1/4 still remaining in my tank. was thinking of alternating shell 91 (0% ethanol) and sunoco 94 (w/10% ethanol) fm time to time. let's say for every 3-4 fill ups in shell, i go to sunoco once. wouldnt that make it a better blend of btwn 91ish to 93ish octane and prolly 1-9%ish ethanol fm time to time too? ive yet to hear of problems with cars switching brands (while still following octane ratings of course). crazy or worthwhile thought?

that may even make my life easier as there's a sunoco station just before i go to the highway. (as opposed to heading over to sidestreet to gas up with shell all the time) - either way, doesnt seem to be a big deal esp in light of mr gold's practice . however, mau did have some poor experiences with ethanol. - working with a small sample size here but useful nonetheless. thanks!

elizabethvitale

My RDX seems to run the best on 76 premium. I always go to the same service station. I think my car enjoys bneing pampetred by the same drink every gas need hahaha