what kind of gas?

[acbaseball186]

as some of you may remember, i just got my car recently and i was wondering what you all pump in it for gas since i havent had to fill it up yet....my mechanic says i can get away with the low test, but should i be puttin in the middle grade? or even high test?? let me know, thanks andy

[_a6_]

i always go with 91+ so high test

[Dos::Avants]

Shell 100% Premium

[Onese1f]

91-93 octane always, you're FI remember?

It's about $6+ extra for every fill up, but cmon now...if you can't afford that, you shouldn't be driving an Audi.

[acbaseball186]

91-93 octane always, you're FI remember?

It's about $6+ extra for every fill up, but cmon now...if you can't afford that, you shouldn't be driving an Audi.

ehh FI, refresh my memory on that lol and no its not about the money, i just wasnt sure which grade to fill it with

[italian a4 1032]

93

[A4 ABT]

Shell 93oct.

When I was in Canada, I always used Petro-Canada 94oct.

[has6]

93, too broke for gas!

[absolutegtr]

Definetly use 91/93 octane

But in all honesty, I would not be surprised if our Audi (stock form ofcourse) can run on regular 87. The car would probably just retard the hell out of the timing, therefore you would have substantial power loss, but still run fairly smoothly.

Reason I say this is because I am sure that their are some unaware Audi owners that put 87 octane in their cars......especially in the times of today

[Onese1f]

Definetly use 91/93 octane

But in all honesty, I would not be surprised if our Audi (stock form ofcourse) can run on regular 87. The car would probably just retard the hell out of the timing, therefore you would have substantial power loss, but still run fairly smoothly.

Reason I say this is because I am sure that their are some unaware Audi owners that put 87 octane in their cars......especially in the times of today

Pshhh..I put in 83, lol lowest possible octane and price FTW.

I have an A6 which is on the brink of death, and with gas prices like this I could give a shit less about preserving this thing. I'm getting a new car at the end of summer and a bike in about a month.

ehh FI, refresh my memory on that lol and no its not about the money, i just wasnt sure which grade to fill it with

FI = Forced Induction = In your case, Turbo.

Its recommended that for FI cars, especially European, that you use the higher grades. I don't know EXACTLY why but I'm sure someone else will chime in here.

[A4_Mike]

I personally prefer to use Shell V Power 93. Check this Wikipedia article out and this "What happens if you use 87 octane on our cars?" discussion.

[kolan67]

you'll save money

[AudiA4Turbo22]

Chevron with Techron my friend! 91-93 octane always!

[initiala4]

93 octane...

[doublezero30]

93 octane. lets say this, my moms got an 07 lexus and uses 87 when the manual and on the fuel door it says 91+ only, and the engine sounds like crap with about 15k on it. its not knocking or anything but it doesnt sound good. i actually care about my car so i like to use what it was built for.

[FromS60toB61.8t]

Shell V-Power 93

[pondside36]

Shell V-Power FTW...

[986Jim]

I use 87, regular. There are a few reasons for this. Please don't tell me that I don't know what I am talking about etc until you read my whole post please. I build turbo motors, have a mid 11 second Talon, a Porsche Boxster which I race (road course and auto-x) and my A4, plus a whole host of other turbo cars in the past.

A few things you should know about gasoline and a turbo car. First off the stock turbocharger is so small that it can run on 87 octane. At partial throttle (closed loop) the ecu has the timing at 40+ deg of advance and the car will run practically on water. When you stomp on it the timing will drop back to 8-10deg then advance as long as the ecu doesn't detect knock. Even with lower grade gasoline you will only lose 6-8deg of timing which will trim off maybe 5hp on a 170hp motor.

My talon has a 60-1 turbo which is 59lbs/min (a lot larger than a disco potato GT28RS or GT30 turbo) and with regular octane the car at 12psi of boost will run 12.8 @108mph with no knock. It's 3280lbs with me in the car so it's making low 300whp to run that number at that weight on 87 octane gasoline. With 118 Mark5 from Pro fuels it's fine upto 26-28psi of boost.

Audi recommends to run higher octane as they don't want the car mainly for marketing reason to have a lower than possible horsepower rating. When you chip the car upto 220hp ish you definitely need the higher octane as chip companies along with higher boost levels also dial up the timing. This will cause the motor to detonate with 87 octane that the ECU could not compensate for so with a chip 91+ is a must. At stock boost levels you will be hard pressed to tell any difference in your car at all, except on a dyno. And with such a measly amount of HP, 170hp, the difference from a few degrees of timing will be so negligible that it won't matter. Kind of like the HP you get from and intake and people saying they can feel a difference. You can feel 3-5hp difference? I have a hard time feeling a 20hp difference on my talon to be honest... My arse dyno is not that strong I guess.

Also with gasoline, lower octane gas has a higher BTU rating, so you will get more mileage from lower octane than you will from higher octane. To obtain the same mileage from 91-94 octane gas the engine will need to burn more of it. How much more on average? Tough to say, but 87 does definitely have a higher BTU than 91 and even more so than 94. This is also generally because many high octane fuels use ethanol with is alcohol to increase octane rating. Anybody who has helped or worked on an alcohol blown race car knows that when you switch from Gas to alcohol you need to double everything because alcohol thigh high octane has a really low BTU rating, half of what gasoline has. So if you have an A4 making 400hp on 660cc injectors and wanted to make 400whp on alcohol you would need 1200cc injectors and also double the fuel pump you had before plus larger lines for feed and return. The alcohol in high octane fuel makes the BTU value even lower than standard gasoline. Great for high horsepower cars, my talon loves Sunoco 94 it's awesome, 26psi on pump gas who would have thought, but not great for mileage. So does mileage matter with my talon? No not really so who cares. It sure does on my A4 however.

I have been running 87 octane in my A4 since I bought it quite a while ago and it runs perfectly normal. If it did run funny I would know and feel it. I have blown 2 engines in my talon and 3 trannies over the last 5 years of drag racing it so I can tell when something is gonna let go.

I'm really not here to argue just give you some info that I have found in my travels along the racing road of life. If you have a chip or other mods to increase your HP over stock by a good margin, then high octane for sure. If your car is stock and only cosmetic mods like mine, then run regular it's perfectly fine. Even in cold winters here in canada (read dense cold air) regular 87 octane has never detonated or pinged or anything else, never mind hot thin air in the summer.

Regards,

[OneBadAudi]

its all about 110 octane race gas....yeh buddy, u cant beat that smell out of the tail pipes :)

[zbrock06]

shell 93 oct. v-power FTW

[AudiA4Turbo22]

damn Jim i read ur whole post! makes sense! i think thats a good way to save money when ur stock! but does it have and disadvantages to parts???

[nick71692]

sunoco 94 Octane

[audipotential]

I only fuel with shell or sunoco. Only time I use esso is if im on 0

[younga4]

I am not going to read everyones post here to comment but a relative accidentally used Chevron 87 in ATL GA.

My horror story is as follows, I drove approx 2 miles and a coil pack blew. Took it to a friends who had VAG and saw hella codes. Replaced the coil pack and added toluene to balance it out I ended up using 2 gallons to balance it out and then drove for about 50 miles and blew a second coil pack.

Maybe coincidence but it did happen after 87 was used.

Like I said though I can not for sure state that 87 single handedly started the crusade for new parts, but it is kinda sketchy.....


Peace fellas you all rock

Young
c.o.a.l.e.s.c.e.

[younga4]

RE: 986JIM

For the most part, he is right. As you remember, dad had a 1.8t in his passat and since he drove like 50k miles a year in it, his gas cost was considerable and since he drove mostly highway stuff on cruise, he ran 87 octane with zero issues. Now, he also didn't floor it much due to the sheer weight that he had in the car and the fact that he was running 87 octane.

Also, he is right about it having more energy per gallon. It actually ignites quicker due to its higher energy content, which is also its major downfall. Since it is quicker to ignite, it is also more likely to predetonate whereas 93 octane is inherently more stable at higher cylinder temperatures and pressures. The reason it is used in higher compression engines is its predictability in the tuning process.
My one problem with running less than the highest octane I can find is that the software in my car, even stock, is that the vehicle tuning was done with premium fuel in Europe which is much better all around. Our 93 is just a compromise to their 94 and to run 87 octane in our cars seems like it would be more or less guesswork for the ECU.
FYI there is a dude with a stock S4 that runs 87 in Texas but he also is never in boost.
Like I said, he is actually right for the most part. However, running the right octane is like running synthetic oil for me: cheap insurance.

Joel

[Colt556]

I use 92-93 since I'm APR1+. I could switch back to stock program but I figure what the hell, it's not that much more to burn better fuel. What does piss me off is that my brother used to deliver fuel to stations in Cali and the stations pay the SAME price for all grades of fuel, they paid for the total number of gallons. Another example of us getting fucked by the oil companies!

[evola4]

I personally only put Shell V-power 91 octane.(we don't have 93 here) I believe on your gas cap cover it says to only use premium 91 octane minimum. It does on mine!

[BSIXER]

I have been using 89 for the past 20K miles (since gas prices started to get rediculous) in my 3.0 with no problems or performance issues.

[bavaria75]

Anybody who puts in the lower octan gas, have you seen a decrease in gas mileage???? You may save 4-6 $ on a tank but need to fill up earlier. You might like to list Octane rating and avg. mpg. Just a thought to make this a usefull thread.

[AudiA4Turbo22]

i don't think Jim is an idiot! he has some proof, but our cars have knock sensors no?? so they will compensate for bad gas!

[drevil2k2]

I just switched from Esso 91 (imperial gas group) to Shell 91.

[acbaseball186]

my input is that i can put in low test in my car, but i will not get the power out of it if i put in 93...so if i want the power, 93...if i want to save money, 87 lol

[BSIXER]

I have been using 89 for the past 20K miles (since gas prices started to get rediculous) in my 3.0 with no problems or performance issues.

I avg. 18.5 mpg. or between 290-310 mi per tank.

[BarryT82]

Remember, just because the pump says 87 doesn't mean it's 87. It's 87 MINIMUM. A friend of mine works for the division of weights and measures and he has to test octance ratings at all of the local gas stations. He said that 87 is usually around 89 or 90 and 91 is always a little higher also.

[TheBigO]

First off, I can't even find a gas station that has 91 octane gas. It's always 87, 89, 93. Anyone knows who carries it in Georgia, around Atlanta, let me know.

Second, I don't know about everyone else, but my car (which is all stock) runs much quieter with 93 in it. Significantly quieter...as in I didn't realize it was on at a stop light quiet.

The first tank I put in was 87, second tank was 93. I figured I'd compare the too and see if there was a difference, then pick one and stick with it.

I didn't notice much in performance, but my gas milage was up with 93 slightly, and with it running quieter, 3-4 bucks more a fill up is worth it.

[dma528]

I have been running Mobil 91 (cheapest around me that isn't Arco)

TheBigO Depending on where you live will depend on if you get 91 or 93, be happy that you are on the other side of the missisippi because you'll have a much harder time finding 93 over here.

[younga4]

i don't think Jim is an idiot! he has some proof, but our cars have knock sensors no?? so they will compensate for bad gas!

You are right I hardly think anyone here is an idiot, I should def not have included that. However, again, coil packs blew within a mile or two after using 87. Not really peace of mind there. IMHO anyway.

c.o.a.l.e.s.c.e.

[younga4]

First off, I can't even find a gas station that has 91 octane gas. It's always 87, 89, 93. Anyone knows who carries it in Georgia, around Atlanta, let me know.

Not trying to be funny but the majority of the stations I fill up at have these options:
87 91 93

...and that 91 sure looks tempting.

That is for Cobb, Gwinnett, Dekalb, and Fulton

I will also add though I have seen stations with only those options you listed
87 89 93

I will let you know exact specifics on which stations when I touch down here again.


c.o.a.l.e.s.c.e.

[TheBigO]

Not trying to be funny but the majority of the stations I fill up at have these options:
87 91 93

...and that 91 sure looks tempting.

That is for Cobb, Gwinnett, Dekalb, and Fulton

Really? Man, I live in Cherokee and never see 91. I work downtown but won't fill up there because of the "city tax" that makes gas 30-40 cents more per gallon.

I'd like to just put 91 in, because they charge 40 cents more for 93, as opposed to 30 for 91.

Anyway, I'll check in Cobb too. I've only gassed up near where I live in the two weeks I've had the car. But I'll venture into Cobb to check it out.

[986Jim]

I am not going to read everyones post here to comment but a relative accidentally used Chevron 87 in ATL GA.

My horror story is as follows, I drove approx 2 miles and a coil pack blew. Took it to a friends who had VAG and saw hella codes. Replaced the coil pack and added toluene to balance it out I ended up using 2 gallons to balance it out and then drove for about 50 miles and blew a second coil pack.

Maybe coincidence but it did happen after 87 was used.

Like I said though I can not for sure state that 87 single handedly started the crusade for new parts, but it is kinda sketchy.....


Peace fellas you all rock

Young
c.o.a.l.e.s.c.e.

I put an EVOM intake on my boxster. Everybody said you're gonna get a check engine light with that evom intake. Porsche guys are really dumb, the more expensive the car the dumber they are generally. I bought it anyway cause I knew it would sound awesome, and it does.

Two days after the intake, boom check engine light came on. I was thinkin what the hell are these guys right? So I pull out my maf sensor and notice that the hotwire is totally covered in road grime and other crap. Previous to my intake it was all the stock filter. So with some electrical contact cleaner I sprayed up the maf and found out there was actually 3 strips to the hotwire, not one. THe other two were so dirty they were black like the plastic and looked like plastic. HOw they worked is beyond me.

I put it back together and the car has been fine ever since. It was just luck and timing that the CE light was the same time as the Evo intake, much like what you were reporting. The lower octane fuel didn't have anything to do with it.

I didn't see where anybody called me an idiot so I will not comment on that, no big deal anyway I have been called worse. However I will be happy to post pics of my previous cars that I built in my garage if anybody would like to see my idiotic 11 sec talon, my Direct Port nitrous VR6 GTI, my RX7, my Boxster, or my Callaway Turbo GTI..