dj55b

iTrader: (2)

I'm going to be doing a series of test over the next month or so of driving from different fuel from different companies. I'll be going to:

Sunoco
Shell
Esso
Petro Canada
Canadian tire
Flying J's

I plan on doing atleast 3 fill ups from every company, and at the same time recording fuel consumption, drivability feel, Exhaust Gas Tempuratures, and if I get a new O2 installed in time, O2 read outs.

Now I know all the runs won't be 100% the same, but it will be all regular city driving and from me keeping track of fuel consumption before I average out pretty good. I do pretty much 1/2 normal driving, and 1/2 spirited so its not like I'm trying to achieve best economy overall.

The reason that I wanted to start this test is because I always used to go to Sunoco to fill up, but doing a run one time I had to fill up and only thing that was near was a Shell, and after driving around for about 20 minutes or so I noticed that the car didn't spit and sputter as much (I run fairly lean with the megasquirt for trying to get as good fuel consumption as possible which is why it does that at very light loads), so going to my trip I came and filled up at another Shell gas station and I did about 5L less than what I normally do. I drive around for another 200km or so and fill up just to see and still below my regular consumption.

So that had me thinking of what the difference could be to have such a dramatic difference station to station already knowing that all the fuel came from the same supplier and most of the other stuff is just additives. Well turn out sunoco seems to have one of the highest Ethanol contents from reading around, especially since they have 94 octane for higher perfomance vehicles which would make sense.

Now knowing abit about Ethanol, the higher the concentration the more fuel you actually need to feed your engine to make it run the same as it has less energy than straight gasoline, which if you have an NA enigne is pretty much a waste of gas and probably power unless you tune your car to compensate for that. But if you have a turbo or supercharged car it will probably help keep things cooler due to the increase in fuel and hence more power to you.

Also another thing about all the big name companies out there, they all use more addivites to clean up your engine and what not which would also result in less efficient fuel perhaps? So thats why I'm trying out some big names and a couple of smaller ones also which will be Canadian Tire (Har, and Flying J's (truckers place with always cheap fuel).

Just to explain the EGT part, and if the O2 can be installed in time, I'll be holding the car in 3rd gear at 4000rpm and recording the readings from that to give out a consistent read out. It normally read around 1300*F which is about the middle of the guage and should be the most accurate area to read from.

If you guys have any suggestion or question before I start the test let me know. If not sit back, and enjoy the ride and info!

Should be starting with Petro Canada first as thats what I have in the tank right now and already have a few numbers.

(null).exe

iTrader: (2)

Dood, Flying J's is all over everywhere! Other than that, I've only ever seen Shell, although my dad has an old Esso Bubble Pump on the back porch. (I honestly thought Esso had gone outta business)

Anyway, back to your regularly scheduled forum.

thunkrd

iTrader: (1)

we used to always use flying j's... and yeah those 2 are the only ones i know. i like to use arco and 76, they are usually the cheapest. and i don't have to drive around wasting my gas

dj55b

iTrader: (2)

Didn't know how big flying J's is down in the states ... its definatly on the cheaper end and not as good of a gas down here from what I've hear. I used to always fill up from there till I found out how dirty stuff is inside the intake. As far as sunoco, I took it out about a month ago and the insides were all clean just like the engine has been put in together then.

PercentSevenC

I usually alternate between Shell, Chevron, and whatever Safeway uses (ARCO, I think).

thunkrd

iTrader: (1)

i always run it pretty hard. that's the only way i can pass a prius

also are you using 87 octane or what? i usually use 87. sometimes i'll premix with 2cycle and mmo

Romulan_7

I always use Chevron 87 octane, no premix. Last time I tried Safeway gas, the car started pinging at ~4500-5k. Then again, I've found enough work that previous owners have done that I'm really not sure what's been messed with. Your results may vary.

dj55b

iTrader: (2)

Good question about the gas octane, yes it will be 87 all across and I do premix in the tank.

Also got some EGT numbers from petro Canada

4000 rpm - 1650*F
3000 rpm - 1250*F

I figured I'd do 2 point ... should be even better. Like I said these are holding a constant rpm for atleast 30 seconds on a flat surface road.

dj55b

iTrader: (2)

sorry guy the number above are actually from Esso not Petro canada as mentioned. First fuel economy for Esso though (keep in mind of my driving style):

31.540L Neted 224km

so that 14.08L/100km

or for you US guys

16.71 MPG

I'll do another EGT read out in the next couple of days.

AntonL

iTrader: (2)

gonna subscribe to this bad boy, keep up the awesome work

Kentetsu

DJ, probably the best way to accurately determine mileage is this:

Fill the gas tank completely, then set the trip odometer to zero. Run the tank down, then fill it all the way up again. Take the miles on the trip odo, and divide by gallons of fuel it took to fill up.

Trying to judge how many miles you get per tank can be a problem unless you actually run the tank dry each time. Maybe you've got a better system, but that is the way I've always understood it should be done.

orion84gsl

iTrader: (5)

We use kilometres here Kentetsu Good idea Sam, maybe I'll start using Shell exclusively when your done with this. I usually just fill up at whatever station is handy.

And Flying J's are all over the place. They have one in Winnipeg, one in Regina, a couple In Edmonton and Calgary, Saskatoon, Montreal and another in northern Ontario. It's actually the truck stop I use the most when I'm in the states, because they are everywhere.

mazdaverx713b

iTrader: (91)

i find that my 7's and 8 get the best performance and fuel economy using sunoco gas. i usually never buy gas anywhere else. i use 89 in the SA/FB's and use 94 in my 10AE and 93 in the RX-8.

thunkrd

iTrader: (1)

by the way, california gas sucks. end of story

blackdeath647

iTrader: (2)

this is very interesting, i usually fill up at the local Wilco, second option would be shell, but citgo seems to suck *** for me lol

dj55b

iTrader: (2)

Hey Ken,

That is exactly what I do and I'm counting it from the same pump and same station so that nothing changes. I don't know if things like how long the nozzle is from each pump or station so that alone could account for a few thing if I did it that way but I'm trying to do it as error free as possible. I think the most interesting test of all will be how EGT's compare ... or atleast for me.

dj55b

iTrader: (2)

What gas stations have you compared it too out of curiosity? Also why use 89 and not 87 in the SA/FB? Does the Rx-8 call for gas with that high of octane?

If you have any info that you remember gas mileage wise comparing both companies let us know. But I know with sunoco, doing about 224 I used to have to fill up about mid 30L of gas. Once I have more data I'll post some up though.

dj55b

iTrader: (2)

Alrighty so I've got another set of Esso numbers, EGT's are about the same so no bother, and fuel consumption is pretty close too here's the numbers for that :

32.885L Neted 228km

so that 14.42L/100km

or for you US guys

16.31 MPG

I'd say thats pretty consistent with the other number. I've now moved on to Shell, and already feel the car drives alot easier like it did before, can't notice the lean spots as easily and drives smoother. Tomorrow I might be going to the drag strip and we'll see how things go there.

dj55b

iTrader: (2)

Alright time for the first set of EGT read outs from shell:

3000 rpm - 1550*F
4000 rpm - 1710*F

Quite a bit hotter than the esso there, what that tells me is that the shell fuel burns easier than the Esso fuel and is what is making the car run better and maybe even giving it more power.

Not sure how this could effect detonation though. So maybe maybe not the best for turbo cars or what not

thunkrd

iTrader: (1)

quick note. you wouldn't want to run a turboed engine on 87 octane fuel. i'd like to see what the EGTs are on 91 octane or higher.

dj55b

iTrader: (2)

I know ... but still usually between companies I'm willing to bet that the 91 from shell will probably still be higher than say a sunoco or something .. but I'll do a test of 91 from one company to see what it does.

'87 turbo II

iTrader: (1)

Also check out www.toptiergas.com, they basically do the same tests you're doing and more and they concluded on Shell being the best. IT has 3 times as many cleaning agents as required by the department of transportation (having more isn't bad for the car but costs the company more to stay with competitive pricing so it comes out of Shell's pocket to give us better gas) and Shell V-power has FIFTEEN times as many cleaning agents. It's really really good gas. I fill up exclusively at Shell.

mazdaverx713b

iTrader: (91)

i have compared fuel from B.P., speedway, and sunoco. sunoco gas seems to last longer in my rotaries. not sure why, as i drive the same. i have been using 87 in my 85 GS which i converted over to EGI but have not vaired locations and have not been sure of exact fuel consumption due to almost all city driving. the RX-8 calls for a premium fuel with a minimum octane rating of 91. lower grade fuel can be used but is not reccomended per mazda. i see no benifit from switching from 93 to 94. 93 seems to suffice and keeps the RX-8 running superb. 94 octane in the TII is a must due to the increase in boot and the knock resistance needed.

Mickster

iTrader: (2)

Intersting all. Will be following this over time. Thanks!

dj55b

iTrader: (2)

Where did you get the data from that site saying that about shell?