morkusyambo

That is not true. I was in Los Angeles for 2 weeks last year and put 93 in my car at 3 different gas stations.

Nubo

California 91-octane is a result of agreements between the CA refiners and the owners of the gasoline pipelines, partly due to CA regulations regarding reformulated gasolines and removal of MTBE. Any CA gas (except aviation gasoline) that's travelled through a pipeline is max 91 octane, as far as I know. This even affects Nevada, which gets their gasoline piped in from CA. I guess it's possible that a local refinery could supply a small area with higher octane.

globi

When you discuss octane numbers you should also mention weather conditions. Especially temperature.

The same engine will perform well with 87 octane, during the Alaska-winter, but could have issues with 93 octane in Las Vegas during the summer.

rx7speed

guys octane is not a rating of how fast the fuel burns. high octane does not equal slower burn speeds while low octane means faster burn speeds. octane is the measurement of how stable the fuel is to automatic ignition. also most engines generally are less prone to detonation the FASTER the fuel burns. engines now are designed to burn the fuel faster and in doing so have reduced how prone the engine is to detonation. part of it is how the fuel burns. slower burning fuels leave more time for perssure buildup and heat to autoignite the fuel. where if your running a "fast burn" designed combustion chamber you can run less timing make just as much if not more power and use higher compression ratio's. the faster burn when ignited burns quicker and more uniform and has less chance to create two flame fronts or other issues.


read up on it a little more you might understand it a little better but octane doesn't mean slower burning fuel.

Spinbreakz

So is it ok to put 87 in my car or not? I live in MN and gas prices are starting to rise. I have a 2005 RX8 with 6 speed manual. Ive been putting in 91, but would like to start to use 87. After reading all the words on this post, im a bit weary, but money is crunching. Will it hurt the engine at all or no? I just need a simple answer

MazdaManiac

iTrader: (3)

As always, lots of bad "science" in this thread.
Lots of misconceptions, hysteria and nonsense.

I won't bother to wake any of you from your slumber again. You know where to go for the answers.

Remember (as always):

1. Your butt is NOT a dyno
2. Concensus is NOT science

nycgps

iTrader: (1)

Theres no answer to that question, to be more specific, you have to find that answer yourself.

Start with 87 for a few tanks and see how it goes.

No biggy

but Im a lazy *** so I just stuck 93 in it all the time.l

Galen Darkmoon

Use premium

swiftnet

I tried using 87 octane, after the third fill up I encountered detonation at > 6K rpms.
I gingerly drove to an auto-parts store and purchased octane boost. After that experience, 90 is the lowest I'll go. YMMV, but definitely pick up some octane boost if you are going to try it, this way you'll be prepared.

Cheers,

Alex

Jax_RX8

I have to agree with MM on this!!!!!

- Higher octane does NOT burn slower - it only has more resistance to premature detonation - which is more prevalent in high compression engines like the Renesis.

- Higher octane does NOT cause more deposits. For that matter, lower octane does not either.

Mazda recommends (but does not require) premium fuel for the 8 not only to resist detonation, but because most gas companies put more detergents in their premium gas - helping reduce carbon buildup.

For instance, Shell 87 has twice the detergents required to be certified as a "Top Tier Fuel" (a great fuel), but their 93 V-Power has 5 times the detergents. Many off-brand gas companies will have the federal minimum (about 25% of what Shell 87 has) and do not add any more cleaners to their premium fuel - so choose carefully.

Also, for those that premix, premix reduces octane and you should take this into account when making your octane choice. If you run premix with 87 octane, you are more likely running 85-86 octane, which I think is just too low. I think mid-grade 89 should be the minimum if you premix.

I suggest using FP60/FP3000 in every tank and then you don't need to worry about gas brand - and you have much more cleaning and lubrication than any pump gas will ever provide alone. I run an off-brand 93 premium (Wawa) with FP3000.

titaniumgr3y

guys you are scaring me !!!! :o

in Cyprus we have 95 octane as the cheap solution.

We can use 95, 98 and 100 unlead petrol fuel!! i have been using 95 octane since i bought my 8 seven-eight months ago and i was thinking of 98 octanes.

So, what is the minimum and what is the maximum?????

swoope

iTrader: (5)

it is different in the states... it is ron vs mon or something stupid like that.

your 95 = our 87. and mine works fine with 87.

beers

titaniumgr3y

89 = 98
and 91 = 100 ? :P
lol...

omg.. for a moment i thought that there are fuels with these amount of octanes in fuel. :P

swoope

iTrader: (5)

usa.

87 89 91.

if you dont live in cali. you get 93 or 94...

your 95 is our 87. your 98 is our 89. your 100 is our 91. same thing different systems of mesurment.

beers

Speed_8

omg my brain is fried.....

jasonrxeight

gees, read the manual.

RufusVonStorm

Jp-7

Novoken

iTrader: (7)

regular and mid grade has always work better than premium in my 8. Also gets better MPG too

mushkid

iTrader: (6)

from the thousands of gas threads on this forum, it is know that using Regular gas makes the 8 perform Better.

xexok

Since it already got bumped by someone might as well chime in.

I know in my s2 it says premium required, so I go with premium. Right now premium is 3.70 a gallon, if I fill up 16 gallons thats almost $60. If I fill up 16 gal of mid grade thats only $2 cheaper than the premium, and the low grade is only $4 cheaper per tank.

Just pay the extra $4.

jasonrxeight

yep

PrinceVince

87 Octane is $X/L.
91 Octane is $X+.16/L
94 Octane is $X+.18/L

If I mix 50/50 of 87 and 94, I get 90.5 Octane at $X+0.09/L.

That's 7 cents a litre cheaper.

Opinions?

Cornbred

I think htis is how the zombie apacalypse starts ... reviving from the dead posts from 1.5 years ago

fuztupnz

iTrader: (4)

Probably not really worth the effort to do so IMO but it would be cheaper i guess.


Actually reviving dead posts is the right way to do it. Much better than creating a new on that asks a question asked 500 times and gets full of useless bullshit like your post newb.

Cornbred

Ya, im the noob, but good feed back with the .. its cheaper answer, im sure no one figured that out and in regard to your comment of the right way to do it, never said it wasnt, just simply stated it was a resurection of a 1.5 year old post. Should look into anger manegment classes, might do ya some good.