What grade of gas do you use???
 

I have an 88 vert, NA and have read differing opinions of what kind of gas to use from 87 to 93

Can someone clear this up??

With an NA the lower the grade of fuel the better so be sure to use 87. TII's need the higher octane and should never be run with anything lower then 93 octane.

Here in Aus,
I only use 98 oct :)

In my TII, 93 to 116.

:D in my streetported TII I run 87 octane, with no detenation and 7-8 psi boost :)

What octane do owners of 89-91 NA use? This engine comes stock with a 9.7:1 CR. IS this later engine equipped with a knock sensor? Does the computer alter the ignition timing based on a lower or higher octane?

TODD

i use 93 when i find it. but i do not go lower than 91 on my bported t2.

Bottom line is, ALL N/A's only need 87 octane, period. If you are running boost it's another story, but N/A's regardless of year only need 87 octane.

Some of you scare me by running your TII with 87 or 91 octane. Not saying that I know everything about owning a turbo, but when I do own one, I know I sure as hell will only use 93 or higher. I dont see the point of risking detenation.

well in the bay area we only have 91 octane readily available, but for the NA lowest octane possible.

I run Jet-A

SImple as this, and THIS HAS BEEN ASKED BEFORE!!!!!!!!!!!!



N/a the LOWEST YOU CAN FIND

TII's are meant to run at 87 octane but if your pumping up the boost and modding get the highest you can find.


An N/a should never need high octane unless you did some timming changes which are too much for 87 oct.

93 octane only.

Does this mean you will make runs south of the border and pick up the good stuff ( I mean the low octane) from down there:) You can ship it to the NA members:)

JAmes

the mazda bible says 87 for n/a and 93 or higher for turbo.

i'm assuming that when i supercharge my n/a i'll need to go for the higher octane as well. which is too bad - like gas prices aren't high enough for 87 octane!

87 octane, always and forever

-Markus

"I use to run 93, cause i was dumb and didnt know anybetter. after talking to some folks i learned" CHEERS!

An N/A will make just as much power, leave less deposits, and run more smoothly on higher grade fuels.

You just have to question cost vs. gain.

I run 93 Oct only at 6K ft elevation, which is equal to running 95 Oct at sea level.

87 octane when I had my NA. 91 for my Turbo II.

Totally false. It's not your fault, the big oil companies spread the BS so they can get more money out of you. Please read:
http://www.ftc.gov/bcp/conline/pubs/autos/octane.htm

Some of you scare me by paying too much for gas that does you no good whatsoever. Higher octane is only required for modified cars, or for engines that are not running well.

Which "mazda bible"? The owner's manual states 87 octane (US).

I would like to see that. :D

I run 93 in my n/a?? it works way better than 87, and i get better gas mileage with it too. and my car pulls harder too. why arent you supposed to use it?

first, how many times has this type of thread been brought up, not to get on ur ass JPA but this has been brought up numerous times. second, Impreza2RX7, i dont know know what u mean with ur post, but changes in elevation wouldnt mean its different octane. if anything it might feel like it. but even then i wouldnt know. the higher alt would just mean that the air is a lot less dense then it is at sea level, which u would feel a decrease in performance, but that different info from what is being discussed. so sorry but please explain to me why 93 octane at 6k ft = 95 octane at sealevel.

and from personal experience the NA loves lower octane atleast on mine. when i first got my car i thought id throw in a full tank of premium, just to clean out any deposits or what not. and it ran fine. but this was my first time owning a 7 so i didnt know how it was supposed to run. then after that tank was done i put 87 in and damn it made a huge difference. my butt dyno says i must have got some good usable HP back.

Thanks for your input Mighty Mouse. I searched first but did not find anything.

You probably have massive carbon build up. lol

Try a lot of high rpm driving with the highest octane SHELL gas you can find and then gradually go down to mid grade and then lowest grade available. If the problem persists I dunno try the water trick.

Santiago

Having both 13B N/A and a 13BT car, their respective (canadian) owners manuals state:

87 Octane
91 Octane

I have never seen that 13BT's where designed to run on 87, like a previous poster said...:confused: