1QWKEVO

iTrader: (3)

heres the thing with octane, don't be fooled octane is basicly how resistant fuel is to combustion, the higher the octane the higher it is resistant to combustion... look at diesel fuels these fuels run off HIGH compression ratio's yet when they burn natually they burn very slow... I don't know the octane of diesel but I know its a very slow burning fuel. Where as with gas if you ignite it get the hell out of the area...

This is where knock comes in when you knock what do u do dump more gas? no thats not always the case, look at the stock evo... it runs pig rich but it still has knock... hello poor octane. Even the owners manual says to run nothing less then 98 RON. It says to run premium when 98 isn't available but i don't think they ment to substitute it completely. What do we do at the track put high octane race gas... what do we do with octane boosters.... See when we have knock we raise the octane to SLOW the Burn down (hense make the fuel more resistant to combustion) But there is a draw back jsut like running a car too lean sure u make awsome power but too much of a good thing can go bad... if you run too high of an octane you will SLOW the burn down too much and what ends up happening is you fuel doesn't burn completely and you'll plug your cat back fire foul plugs and a whole mess of other junk but mainly LOOSE performance. The best octane to run is what was recommended for the car as the ECU was tuned for that octane, also when parts are added or fine tuning is done run whatever octane provides the least amound of knock... never run more then needed as it will only reduce performance... so all these guys dumping 100 octane in their 1987 honda's are just wasting money and slowing the car down... There are many other factors with fuels that i'm not even goign to get into for the sake of a short post but this is one of the main things people should know about fuels. I'm not sure if this has already been said cause i didn't want to read through the whole post to look for it but even if it has oh well... my 2 cents hope it helps

PVD04

iTrader: (23)

Actually, diesel fuels don't even have an octane rating, it's a cetane rating. If you were to put diesel fuel in your car you would have nothing but knock. You were correct when you wrote that octane rating is how resistant fuel is to combustion, but when you started to write about burn speed, your info was somewhat deceiving. The purpose in raising the octane is not to slow the burn rate down, that is merely a negative side effect of raising the octane of fuel. Higher octane fuel is used because it can withstand higher temperatures and pressures without spontaneously combusting, not because it burns more slowly.

Also, adding more fuel does help to reduce knock. It does this by reducing temperatures in the combustion chamber. Leaning the car out causes higher combustion temperatures, which in turn increases the risk for pre-spark combustion, or knock.

Finally, your comment about 98 RON being recommended for the car, RON stands for Research Octane Number. In the US, octane ratings are given as (RON+MON)/2, where MON is Motor Octane Number. 93 (RON+MON)/2 is pretty much the same as 98 RON. So filling with 93 is what is recommended.

abalto

My record was 702 miles to one tank.

Of course that was in my Honda Insight

1QWKEVO

iTrader: (3)

Yes you are correct and as I thought i mentioned i wasn't too sure about diesel fuels... anyways i can understand what your trying to state abotu the slower burn and yes adding fuel does lower knock but its not a simple function putting sometihng in doesn't always result with the same product and vis versa.... The evo is a prime example in stock form. The reason I used RON in stead of PON (pump octane number) it is very hard to give an EXACT pump octane number which remains true for all pumps. even with that forumula which is posted on every pump. Gas is mixed or if you would, dilluted from a MON number but if you ask someone what is the MON number no one will tell you... its basicly a combination of the two... some fuels use higher mon's vs rons and some use them vis versa ... if you ask me this is what seperates the " Good" fuels from the "Bad" fuels is this mixture...

VTECH8TR

iTrader: (70)

Ummm. He is flashed, read his sig.

lil'evil_evo

iTrader: (17)

How the hell is this possible? I have only hit above 250 1 time I usually get approx. 240 and that's only boosting 17psi driving good on the highway.

lil'evil_evo

iTrader: (17)

JFawns

My city mpt is usually between 160-180. I don't do much highway driving but I was able to hit 260 on a tank once.

Jeb

Dragonfly5338

iTrader: (1)

332 - break in period. Average is about 200-250 per tank.

GREDDY

iTrader: (8)

280 miles on average.

evo82003

iTrader: (1)

i got 234 but i was running the a/c too. i guess with the a/c off ill get alittle more and of course if i dont speed up(2 the speedlimit).

justchil

iTrader: (44)

I don't have a record on tank but my last milage was this:

260 Miles : 9.957 gallons == 26.11 mpg

Very happy with that.. That would be 365 miles to a complete tank

WildRice

18-23 MPG, I never drive for mileage and seldom take trips in it. I often run 100 octane RON unleaded and the car does run better on that.

According to my fuel wholesaler "Northern Lights Energy" in Redding CA, MON is difficult to calcultate as that depends on the actual condition of the fuel (for example; the fuels' age and how it has been stored will affect the MON #).. RON is theoretical for fuel in perfect conditon before storage and any deterioration. The estimate he gave me for his 100 RON unleaded is 96 or 97MON which is about 98 RON + MON/2 but he is guessing. It does seem to work better if I mix this fuel about 2:1 with 91.

justchil

iTrader: (44)

My numbers above were about 85-90% highway.. took a trip. It was decent weather too.. kind of cool.. probably 60's with almost no humidity.

thebluesky

iTrader: (28)

my record is 352 . this is only when i was commuting to work an also before one of my fuel injectors went bad (it was dumping extra fuel and replaced it last thursday).