AlwaysinBoost

iTrader: (17)

Recently I started to tune my EVO with software that enables me to see when the engine is experiencing knock (search:EVOScan program). Lately the weather here in the NE has been EXTREAMLY hot and humid, average temps are in the 90s and humidity is 100%. I never really paid much attention to where I got my gas, as long as it was a busy station I figured all 93 octain was the same. During the week I filled my tank up at BP which is also known as Amaco fuel. After a couple of days of logging and tweaking the software I was pretty happy with how my EVO was performing in the extream heat. Again I didn't have a second thought about the gas that was in the tank.

Last night the woman and I go out for a bite to eat. After dinner I filled up at the local WAWA for $3.19/gal and went right home. This afternoon I went back out to do some more tuning in the cooler weather (about 10* cooler and 30-40% less humidity) and to my suprise I was seeing a lot of engine knock on my logs. I couldn't understand what was going on, it made no sense, the weather was cooler so the engine shouldn't be knocking at all. It wasn't until I realized that the only thing that changes since the day before was the fuel I was using.

I had heard stories about some stations having bad gas but never actually 'felt' the difference until today. Luckly I only put about 10 gallons in the tank since I planned on going to the track this week. Now I have to try and use up this crap fuel so I can fill up with the good stuff.

So a word to the wise if you want the best performance out of your EVO don't fill up at a WAWA.

4Gsixty3

iTrader: (13)

wow, finally someone prove that not all gas are not equal!!! i only put Sunoco, Shell and BP in my evo.

EvoDan2004

iTrader: (94)

same here il run out of gas befor i put anything other then sunoco in my tank.

4g63skeet

i've heard that chevron is the best. its not great for performance but it'll supposely prolong the life of your engine.

DynoFlash

iTrader: (91)

The sad reality is that the consumer has no way to really know what is in the gas you are pumping

Contamination, stale gas and rip off scams seem quite common

I think the best protection that people can take is to go slightly conservative with tuning when running pump gas, particularly in the a.f targets

I have long thought aboyt doing a study of various fuels to determine the advertized and actual octane values , I am thinking it may be of little value as the quality fo fuel seems to vary from day to day

I think as far as fuels go the best path is to stick with a large national chain and try to go to large gas stations with high volume

nothere

iTrader: (23)

here, all the gas comes from the same refinery, the only difference is the additives they put in the tanker truck. the driver picks up a load, adds a packet of stuff and out pours that stations gas.

.50 Cal Cow

iTrader: (2)

always use sunoco whenever able. but more because i work at a sun refinery anyways and like to support the company.

ntm for those who care sunoco doesn't use any crude from the middle east. plug plug

.MM

iTrader: (3)

for all you hardcore shell fans, SHELL SUCKS!!!

shell is as bad as the cheapo gas companies

everytime i ran shell in my supercharged type R, i will detonate

sunoco, mobil and their little brothers (exxon)

FOR LIFE!

cdupont03

iTrader: (31)

Yeah it sucks cause I always used the 94 octane at Sunoco, but I just moved and I cant get it here. So now I am running 93 from BP. It does the job but I still liked the Sunoco better.

sesso

iTrader: (4)

to me it depends how much water is in the tanks. Companies are allowed a certain amount of water in the gas.

elhalisf

iTrader: (171)

actaully the colder air will increase the chances of knock, because of the denser air charge. for example, if someone tunned their car to the limit of no knock on a hot day, then they will experience knock on a much colder day. happened to me when i was tunning my galantvr4.

Evolved Monkey

iTrader: (1)

I remember reading about this in a Car and Driver article about a year ago. Some car manufactures actually did fuel testing themselves and concluded that these had the best fuel :

QuikTrip
Chevron
Conoco
Phillips
76
Shell
Entec Stations

full article: http://www.caranddriver.com/columns/...y-webster.html

Ninj0x

iTrader: (3)

I read in one of those car magazines (Modified, I think), that they did do a fuel test for 91 octane. I don't remember the article exactly, but the conclusion was that 76 gas was the most consistent and knock resistant and now thats all I run.

Ninj0x

iTrader: (3)

It seems to me that the article focuses on which gas keeps an engine clean through additives, not if the octane specified is accurate. The article even states that putting in a fuel with less than the recommended octane will lead to "very small horsepower losses," which may be a fallacy. This leads me to believe that power is little concern to them.

I would also like to point out that the list you posted is in no particular order.

Greg K

iTrader: (2)

I have a related question; what did the boost log look like with the cooler temperature? Cooler ambient temps will cause the boost level to increase (when using a MBC), and that may have contributed somewhat to the knock events. I'm not discounting the possibility that you have have gotten a tankfull of skunky gas, but I wanted to cover all the bases.