i believe that our cars are factory tuned for 93 octane so 91 pisstane isnt cutting it well.

but when i mix 100 octane into 91 octane to make 93...i notice that i get better gas mileage and the car performs better and for some reason, i feel like it shifts better too. lol

 

93 is definitely better then 91, its not just in your head. Coming from only using 91, it felt like a first mod (yea I know its not, but it feels better) Not sure about the shifting though. Oh and to the OP, the lower boost is fine, when I switched to 93 I noticed mine also dropped slightly, but it was pulling just as great.

 

Yup Im never going back to 91. It sucks tho that there is only one gas station in my whole town that sells 93.

As far as the boost. So basically since im running 93 I have to raise my boost back to 18 psi with my boost controller right? Or should i just leave it as is until i get tuned for 23 psi?

 

You guys are all running your Evos on Octane 91 or 93?

Here in Singapore, the manual states that the recommended Octane level for a JDM Evo is Octane 98.

Btw, it is $1.50 per litre or $5.70 per gallon here

 

It depends on how the octane rating is calculated. Im going to cut and paste because its quicker than me explaining it lol. This is from wikipedia, but its still accurate:



Measurement methods

The most common type of octane rating worldwide is the Research Octane Number (RON). RON is determined by running the fuel in a test engine with a variable compression ratio under controlled conditions, and comparing the results with those for mixtures of iso-octane and n-heptane.

There is another type of octane rating, called Motor Octane Number (MON) or the aviation lean octane rating, which is a better measure of how the fuel behaves when under load. MON testing uses a similar test engine to that used in RON testing, but with a preheated fuel mixture, a higher engine speed, and variable ignition timing to further stress the fuel's knock resistance. Depending on the composition of the fuel, the MON of a modern gasoline will be about 8 to 10 points lower than the RON. Normally fuel specifications require both a minimum RON and a minimum MON.

In most countries (including all of Europe and Australia) the "headline" octane rating, shown on the pump, is the RON, but in the United States, Canada and some other countries the headline number is the average of the RON and the MON, sometimes called the Anti-Knock Index (AKI), Road Octane Number (RdON), Pump Octane Number (PON), or (R+M)/2. Because of the 8 to 10 point difference noted above, the octane shown in the United States is 4 to 5 points lower than the same fuel elsewhere: 87 octane fuel, the "regular" gasoline in the US and Canada, is 91-92 in Europe. However most European pumps deliver 95 (RON) as "regular", equivalent to 90-91 US (R+M)/2, and some even deliver 98 (RON) or 100 (RON).

 

Thanks, I will check it out

 

93 octane around here is rampant. 89 / 91 / 93


Always put 93 in the bike and the Evo always.

 

I believe it translate to more like $4.95/us gal and $5.95/imp gal.

 

Is there not 3.7 liters in a gallon?

 

does anyone know where i can find some 93 oct near Naperville, IL????

 

It's more like 3.8.

1 U.S. gallon = 3.7854 liters

Edit: A British imperial gallon = 4.545 liters

 

yeah up here in hagerstown md, 93 is 389 prices are still dropping though so we will see how long that lasts. it was up to 410 420 at one point

 

I've been reading threads about gas prices and people looking for different stations close to their area. So I figured I'd give you a hand with finding who has the cheapest gas prices...ENJOY!

http://autos.msn.com/everyday/gassta...?zip=&src=Netx <http://autos.msn.com/everyday/gasstations.aspx?zip=&src=Netx>

 

what station are you going to def?

 

lauerl md 3.45-93