Mazda_RX804

I used Ultra 94, since ive got my 8. When the gas stations used to be Sunoco's (Which were awsome to get performance points, and getting free tanks of 94 gas), but now I get it at Petro Canada, Shitty points system.

tonik

those are the days the ecu's,oxygen sensor wasnt invented and fuel quality really crapped..
are there any threads here about people blew up there engine because they use 87 octane and **** happen,detonation or pre ignition?

tonik

i filled up 48-50l
again, im not after savings here.
i want my 8 to be a guniea pig for 87 octane..lol..
as of now, 136xxx km in odo..ive been running 87oct around 100xxx km..

LifeAfterRx8

iTrader: (17)

I usually use Shell V-Power (93).

Carbon8

iTrader: (4)

I run Diesel only the good stuff, or K1 if its available.
My Wankel Loved it.

Ka Kui

iTrader: (7)

I put Shell 91 in my RX-8

nowakm99

I was using Ultra 94 and thought that it was the best stuff going, but then was forced to stop at the Shell near Cayuga TMP before doing a track day as it's the last station before you get to the track from T.O.. I reluctantly filled up with V-Power. I don't know if my mind was playing tricks on me, but the car felt peppier on the V-Power gas, so when I got home I went online to do some research on different gas in Canada.

That's when I came across all the negative press on the ethanol content of Ultra94. Since then, I've been alternating between Shell V-Power and PetroCan's 91, both of which are ethanol-free. I only get the PetroCan as I have a 5 cent discount for about 1,000 litres of gas. Other than that it's Shell V-Power all the way.

Snrub

Gas is gas.

I was buying Pioneer gas because they were the cheapest. When I first started using them 91 octane was $0.10/L over 87 octane. Their 87 price was always a couple of cents a liter cheaper than the major chains. Their bonus bucks program mean $0.90 off a typical purchase. Then they cranked their price of 91 octane to 0.12/L and now 0.14/L over 87 octane. As a result I've started using Superstore/Loblaws gas. It's $0.12/L over 87 and their program gives you $0.02C/L in coupons at their stores. Additionally, recently Pioneer's prices on 87 octane have been a lot closer to he major brand prices. I have a MBNA Smart Mastercard which give $0.03/L off gas (introductory is $0.05), 3% groceries, 1% everything else, no fees. There are a couple of cards that might be better for exclusively gas.

alnielsen

iTrader: (4)

Not true. I used to (until a week ago) work at a BP refinery. BP sold their fuel to various different distributors. Each had a different blend that they specified. This blends would contain different detergents and specified quantities of alcohol. Because alcohol boosts the octane, it is cheaper to add than conventional octane boosters.

nowakm99

I'm assuming that you're trying to be provocative by saying that gas is gas. I doubt that there is significant performance difference between the different brands (although my car did feel different on V-Power than on Ultra94....maybe it's in my head), but one thing that's certain is that the additives that you get in high end gas from places like Shell are there for a reason and will likely make a difference in the long-term.

Snrub

No, I'm not trying to be provocative. If you disagree please feel free to post some data which demonstrates that one gas is measurably better than another and the proven benefits we can expect. As mentioned above, there are differences, but they are slight. There are also differences between the products produced by different refineries. Again as mentioned above, in a given area one refinery may sell to a competitor, not just independents.

Top Tier gas is the closest thing to endorsement of quality, but it has to do mostly with depots left on valves and injectors. It seems now most of the major bands are Top Tier. If there was a major difference auto manufacturers would do more than make a tacit recommendation, they would make a strong recommendation or use wording similar to that used to describe the subject of 87 octane in our cars. If we take Pioneer as an example, is it top tier gas? It's not certified, but they purchase from Petro-Canada (40% owner I believe) and Esso. Both are Top Tier. Does it lack the additives or is it something else such as inconsistency of blend due to who they purchase from, or pressure from their owner not to become certified? It's impossible to know.

Snrub

In the Dec issue Grassroots Motorsports did a comparison with a 1.6L Miata running a megasquirt ECU with a DIY autotune on-site supporting their efforts. They adjusted the tuning to maximize the output of each fuel.

Here are the results for each type of fuel:
93 E10 / 93 E0 / 87 E10 / 100 / 105 / E85 / Methanol
power: 136 / 134 / 135 / 137 / 137 / 143 / 160
torque: 124 / 122 / 117 / 123 / 124 / 128 / 140
fuel correction: 0 / -2 / -2 / -2 / -4 / +63 / +92
timing correction: 0 / 0 / -1 / +1 / +3 / +2 / -2

It would have been nice to see a few different cars, perhaps a factory turbo car and a modified turbo car. However, it proves that Shell pump gas does not deliver superior performance due to it's lack of ethanol. This test suggests non-ethanol laced gas is actually slightly worse for performance when tuned appropriately (difficult to say how this would affect OEM tuning, but it seems unlikely to have the opposite result). An obvious conclusion from this test is that alcohol cooling properties can have awesome performance results when the car is tuned accordingly. The other is that after a certain point, n/a cars without radical engines do not benefit significantly from high octane fuel, even with appropriate tuning.

rx8boomer

LOL ..... ill be a monkey's uncle

Cyclops_JAPAN

Last November also there was this CBC 'Marketplace' speaking about different types of gas. They made a comparison using a Chevrolet Cruze if my memory is correct, a car that normally requires 87 or 89 octane, and ran three tests: power, mileage and emission levels. The test were ran in a Toronto institution, I can't remember if it was governmental, but the results for the test using the 87 or 89 and the 91+ gas were equivalent, at least regarding this three parameters.
There's also an interview with a spokesperson from an oil company or something like that and he happened to be evasive when asked and showed the results. Basically his message was 'read your manual and use the gas listed there, we offer something better for those that want it'.

The question that rises against him is "what's exactly something better". He didn't tell. However we cannot forget that something very important was not tested in the program (for obvious reasons): long-term effects of using 91+ gas in a car that only requires 87-89.

Of course we're talking here about a car with a piston engine and around 100hp, a bit different than our reality, but I consider it valid information. Ah, and I use Ultra 94 all the time. I stil didn't decide whether I'll continue like this or go 91. Next summer I'll have to decide!!

Regards!

P.S. Here's the link, the chapter is called 'Pump Fiction' Marketplace - Canada's Consumer Watchdog

Unoriginalusername

Check out this fifth gear comparison of fuels. Starts about 30 seconds in

GTDave

I have had to use regular fuel on several occasions because no super was available. I did notice a little bit of ping under excelleration with regular but when I used mid grade 89 octain I had no such issues. If you use 87 just keep the engine reved up a little more and you won't get the ping. If you are using 87 and have had no issue in 100k then who are we to argue with success. At 10 to 14 cents a litre more that can add up to a bit of money over the year. A hundred dollar savings between oil changes covers that and air filters too. Some places do offer mid grade at regular price and I go to these statins when I am in the local area.

Boeuf

iTrader: (2)

I just find it funny how everybody that uses regular or mid grade fuel are great at justifying it rather than just admitting they are cheap. If you can't afford to drive it, sell it and buy a more fuel efficient car.

alnielsen

iTrader: (4)

The same can be said about people that don't use the recommended oil specified by Mazda. Many are of the opinion that it isn't optimum and justify their reasons for what they use.
Are you so sure that you aren't wasting money buying too much octane? You will only know if you make a change and try something different.

Boeuf

iTrader: (2)

I'd be willing to bet that 91 octane is not too much octane and that the engine still performs better with the recommended octane rating. I'll agree that a higher octane than 91 most likely will not aid in performance, at least not on a stock na RX8, but I would bet running a lower octane will most likely affect power, fuel economy, and make the engine more susceptible to detonation.
Regardless of any of that, these are sports cars that get poor fuel economy on the best of days, if fuel economy and prices are that important to someone then I'd say they fucked up and bought the wrong car.

200.mph

iTrader: (9)

93,94 and once in a while when i can find it 95 and always premix. my car is like my kid

thewird

Using 94 in an N/A RX-8 is kinda silly. I'd bet there is a power loss on 94 from 91. Use 87 if your cheap, 91 otherwise. 94 if you want to say you use 94?

Now if your car is boosted, please use 94 and nothing else

thewird

ShellDude

iTrader: (12)

I have a gas card that gets me 100

and it costs like $120 to fill up!

for DD I try to do Sunoco 93

GTDave

Sorry that we don't meet up to your ideal RX8 owner. To tell us we FU because of something we have tried with our own vehicles is arrogant at the very least. We bought the RX8 because we liked it. You certainly won't change that with your post. Some people have driven 100000s of kilometers using 87 with no problems. It's hard to argue with that.

When I drive in the states I get better mileage but if I am on my bike it knocks indicating they have a lower octane there. I guess it's like anything else. Personal choice. Some will use 5W20 oil as recommended, others won't. Some will use 75W80 in the rear end others will use 75W140. I guess what ever you think is good is fine by me. Just give us the respect we as RX owners deserve.

ShellDude

iTrader: (12)

Before I boosted I ran 87 no lead once and she just didn't feel right... idle was rough and she knocked... no doubt about it.

Perhaps our gas is just that much more shitty here.

The only thing Boeuf said that was remotely confrontational was that he called out price minded folks as perhaps making the wrong choice buying an RX8. It's nothing personal, but it is a statement of fact. He didn't call you any names and I'm sure no disrespect was intended.

thewird

It is a fact that the car idles a little rougher and tip-in isn't as crisp on 87 octane fuel. I can also say that the difference is small and you only really notice it if your paying attention. I personally do not like the idea of running 87 in a rotary engine but can also agree with that it is safe to do so. Now if you consider the fact that 91 octane fuel tends to be cleaner then its 87 counter-part as they usually have more cleaning agents in it, then its not a good idea. But at the same time you can occasionally put 91 in and hammer on it to "clean it out". At the end of the day, use whatever you want LOL.

thewird