what kinda fuel you guys puttin in ur RB's?

[MOB240]

do any of you use race gas 24/7 or just for track use? the highest octane ive seen around my area so far is 91!

[wawazat8402]

I run 93 octane only. Its hard to come by here as well. AFAIK, there are only 2 gas stations that offer it in the Oklahoma City area, but luckily one is about 4 miles from my house and the other is 1 mile from work.

[gbaz77]

yeah, out west has it bad.

here in Maryland, 93 is at every gas station, and if you go up to New jersey, sometimes you can get 94. its crazy.

every now and then i'll treat my self to some octane booster.

[FriedEGs]

I've used Sunoco GT100 before, but, I really had no use for such a high octane. Even though Japan uses 100 octane, it seems our cars don't really benefit unless you're boosting a considerable amount, like 400hp +. Look up sunoco GT100 and you can get a list of local Sunoco's that offer it in your area. The price doesn't change much, it's been around 5-6 bux a gallon for the past 10 years. Also, your local track my provide it also.

For the most part, I just use "Top Tier" gasolines, such as Texaco, Gulf or Shell.. (93 octane if you can find it). Just stay away from the speedways, and bp's, that add too many additives that aren't teh best for our Japanese motors...

If you want a list of "top tier" companies, i'm sure you can find a list online..

[Joe]

the highest gas we get here in az is 91, so just run that.

and japan's octane rating is different than ours (RON vs. AKI). it says 100, but it works out to about a 95 on our system. there is no need to run 100 octane in a car that doesnt need it. you will only go slower.

[FriedEGs]

yea, i can't remember.. I think it's the RON + MON divided by 2 gets the knock index. (which differs from country to country)

but, only use what your motor needs for your application.

We're lucky in the Midwest. 93 octane is readily available at 80% of our stations and Sunoco 94 is not difficult to find, either.

[MOB240]

so whats the point of octane booster? its useless unless youre running high hp? oh and btw kamin i think i saw your car @ nicofest lol...did it have a denetsu decal on the rear quarter?

[FriedEGs]

basically raises your octane level up a few points.. instead of say 11% ethanol mix, it increases teh octane rating... but, really it can't get much lower than 4-5% ethanol.. (don't quote me on that) in other words.. it will increase your octane rating close to that number if you use 87 octane.. but, adding this to 94 octane will not increase the ratio much more than that...

i don't know why there are soo many octane boosters on teh shelf at the autoparts stores. especically in our area where octane levels of 93-94 are readily available.. i can understand those that need it in places where premium is difficult to find.


Modified by FriedEGs at 10:39 PM 4/8/2007

[Joe]

so whats the point of octane booster? its useless unless youre running high hp? oh and btw kamin i think i saw your car @ nicofest lol...did it have a denetsu decal on the rear quarter?

octane booster is a scam if you are already running premium

and yep, its still on there. densetsu is one of my sponsors. i took 2nd on friday in the qualifying but the car took a dump before practice/pro qualifying on saturday so i had to drop from the comp.

[eh?]

I've used Sunoco GT100 before, but, I really had no use for such a high octane. Even though Japan uses 100 octane, it seems our cars don't really benefit unless you're boosting a considerable amount, like 400hp +.

That's not really true. If you wanted you could bump up base timing on the stock ecu to take advantage of higher octane at LOW boost. That way you'll have extra power without extra boost. The stock RB25 low end power really picks up power when timing is added at the low end.

[rustbucket]

octane booster is a scam if you are already running premium

Octane booster is a scam, it only adds an average .5 or so to the octane rating. If you really want the extra octane level mix toluene with your gas, of course research this before you just add a bottle of it to your tank.

Toluene R+M/2...114 Cost...$2.50/gal Mixtures with 92 Octane Premium 10%...94.2 Octane 20%...96.4 Octane 30%...98.6 Octane

[Carl H]

we have 100 octane at almost all petro express stations here, but seriously...only run the highest you can find dont EVER think about putting in 87.

[Darius]

I'll be the one to throw a wrench into the spokes.

In Iowa I have only found 93 at BP and some only have 87 and 89, which is the 15% ethanol blend. What are your opinions on the ethanol if no other gas was available and you were out? 87 or 89 w/ethanol in the worst case scenario?

[Carl H]

while ethanol will burn much quicker i still would go with the highest octane possible, when running on ethanol blends while i was in ny i found that i wasnt getting as good gas mileage as i had been running straight gasoline.again highest octane possible, dont want to induce knock...

[Sil240]

What????Darius are you serious???There are gas stations that don't have Premium???

Octane is the resistance to detonation87=87 doesn't matter

If I were you I'd look into the Toluene.But becareful because if your using a lot of it, it's hard to light it off.You may create a mis-fire.

Octane boosters are crap in a bottle.$12 for .5 Octane the most!!!

Kamin how will runinng 100 octane gas mak you slower????

You will just be burning expensive gas unless you tune for it, or advance your timing.It's also a little more cushion if your motor.

I wouldn't reccomend it though, I don't have $$ to burn like that. I would go Toluene, pretty cheap compared to race gas.Or do Meth injection, only when you need it.But that's if you are running big numbers.

[Darius]

Yeah some po-dunk gas stations don't carry premium. Hell, Casey's is a big chain gas station company that prides itself on being the small town station and they NEVER carry premium, just 87 and 89 w/ethanol. The only thing we really have in my neck of the woods is BP 91 or 93 can't remember.

[lucky7]

like in ohio, i would say 9/10 stations have 93 here. and 2/10 have 94. its the no-name mom/pop gas stations in the boonies that only have 91.

[Carl H]

running 100 octane wont detract from performance but if anything help.the ecu is an active device, it will advance timing as far as possible according to the timing map as long as it doesnt hear knock, if it hears knock it throttles back timing till it goes away then mantains that much advance...if it hears excessive knock it swtiches to the knock maps.

[Joe]

Kamin how will runinng 100 octane gas mak you slower????

Octane is a measure of how hard it is to combust fuel.

the higher the number the more energy it takes to burn. that means the harder your engine has to work to burn it. if 91/2/3/4 octane is knocking to a point where its unsafe you need to up the octane.

OCTANE DOES NOT EQUAL HORSEPOWER. i always love people who put race gas in cars that have NO need for it.

[Sil240]

http://auto.howstuffworks.com/question90.htm

"The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting."

Yeah a lot of people do think that higher octane = horsepower. lol

Ditto what Carl said!!

[eh?]

Octane is a measure of how hard it is to combust fuel.

the higher the number the more energy it takes to burn. that means the harder your engine has to work to burn it. if 91/2/3/4 octane is knocking to a point where its unsafe you need to up the octane.

OCTANE DOES NOT EQUAL HORSEPOWER. i always love people who put race gas in cars that have NO need for it.

Octane is the measure of a fuels resistance to KNOCK. It's NOT harder for it to burn. IT's harder for it to PREIGNITE. You're talking like the stock ignition will have issues burning high octance fuel which is false. It's SLOWER to burn and that's why 1) you can advance timing and gain power 2) it can leave deposits if timing isn't advanced

[Carl H]

just to rehash:lower octane fuel is much more volitle, thus easier to ignite; so its easier on the engine to combust but it tends to want to combust on its own hence the need for retarded timing.

higher octane is much stabler but it is harder to combust, but it is less likely to try and combust before it should (preignition/knock).

moral of the story is: dont run anything less than 91.

[OpeLok]

moral of the story is: dont run anything less than 91.

unless your road trippin and not boosting

[Bronze MFP]

was running 93, but last 3 tanks I have use 100 octane. first just for sh!ts n giggles, but i'm pretty sold on it. engine runs smoother, has better response and pickup, and feels stronger in the high end as well. the only explanation I have for this is that maybe the 93 was pinging some and the ecu was pulling timing. who knows, but I could tell a difference. i would love to dyno prove this though


Modified by Bronze MFP at 8:36 PM 4/10/2007

[FriedEGs]

I'd be interested to know also. ^^^^

what kind of setup do you have? #'s.. etc....

[Sil240]

Anyone ever thought about Secondary injectors?

Stock set for cruisin and then a larger secondary set for high boost.

I was looking at the Spectre performance version of the Mega Squirt system and it can do secondary's.

Or running a seperate tank with race gas.

[Carl H]

secondary injectors is tuning a car from the 80's, back when programable engine management wasnt avalible.i run 720cc injectors and get 28mpg on the highway and 20 in town...its all in the tune.