I used 93 all weekend with my SC Cortex in 91 mode.....no problems. Felt nice to have that extra bit of power on the interstate.

 

why do you run 93 for no reason

 

keeps engine cleaner and 30-50 mpg more per tank

have u ever looked inside an engine over 100k that ran 87 only... its dirty
with 93 it stays clean

 

i have, in high school i had a debate with my shop teacher about that and running synthetic oil vs. conventional. at the time he had a chevy truck with 160,000 miles run on 87 octane and conventional oil. internals were like new. its a waste of money and doesn't do anything for you. i read somewhere that if you run a higher octane than you need it will actually create more deposit. if you want to have more of a need for 93 octane go get a 2* advance

 

While what you talked about with deposits and higher grade fuel IS possible with lower compression engines, in an engine like ours where the compression is much higher and cylinder head design is advanced, running high grade fuel usually results in a better burn than low grade fuel.

I don't know how some of you cannot tell the difference between running 87 and 93 (we have 93 around here) - it makes what i would quantify as a huge difference considering it's only 6 points of octane higher. Its very noticable in my truck.

As for synthetic oils, the purpose of sythetic oils is better lubrication through the durability of the material and the fact that it's molculer structure is smaller. Synthetics other main reason for being used is breakdown resistance and because of this, does not need to be changed as often. Most people running a good synthetic such as amsoil will change there filter every 3-4k, and the oil every 12k.

 

interesting

I guess thats why they didn't make 93 tune program

which gibson do u have the Side and stainless or dual rear one ? Hows quality and power? Do you get a bit more low end torque?

 

I guess thats why they didn't make 93 tune program

not to mention 93 octane doesnt exist in half the US.

 

i have side stainless. it has a real mellow tone, smooth sounding not to much louder than stock. maybe 20% louder. i didn't feel much of anyhitng on the top end but i felt a difference where it matters for everyday driving. 2k is where i liked the improved performance. i believe the dyno was 12 hp and 12 lb of torque, not to sure, but i would buy it again.

 

I have yet to find some 93 Octane here in Utah at the pump, all I have found in the last 30 years is 91. I use 88 though just because that's what I have always used in my cars with the exception of my wife's civic which has a turbo that one I use 91 only

 

I've run 91/93 depending on whats around. I have a fairly modded motor so I see a good gain from it along with the superchips tuner

 

I am stock but I use 93 only since day 1.

so, how is it that you know you get 30-50 miles more per tank if the above is true? How many miles do you get out of a tank? What mpg? I've run 87 and I've run 91, no difference in mileage or perceived power and when the butt dyno reads no change, it probably isnt there.

do you know what the octane rating means? Higher octane can sustain higher temperature/pressure before spontaneously igniting (detonation) however, running higher octane when not needed can actually cause it to burn less cleanly.

Run 93 in an engine designed for it, run 87 in an engine designed for it and all will be good. With mods, I can see potential for power gain from higher octane but stock engine with a stock tune, I dont see it. (and for those of you who disagree, show me a dyno proving more power with 91/93 than 87 on a stock motor).

(edit: maybe I'm wrong about 93, maybe 93 does something that 91 doesnt but it's not available here so I cant test it.)

 

i've never seen 93 octane in texas..and have never even heard of 100 octane except for those octane booster cans you pour into your gas tank. I know with the power pup, you can run the premium tune(recommended 91octane) with 89-90 ocante fuel if you're not close to sea level.

 

What part of texas are you in? In the southeast texas area its very easy to get 93 octane. I've never put anything but 93 in my truck. I do have the 93 octane tune from Uprev, so while I may not have gotten any gains from it before, I actually need it now. I told them not to even bother with a 87 octane tune. I have 93, economy, valet, stock, & still one empty tune.

 

uprev has a 93 octane tune

 

well I live in NJ we have 93 used to have 94 and 100 at Sunoco

1. the mpg Q - Around 5K I did A test with 3 tanks of 87 - 11 to 12.5 mpg city. Then back to 93 - after one tank back to 13.5-15.5 mpg city
After the first synthetic oil change at 13K - 15-17 mpg city
All numbers are with stock programing and drop-in K&N filter

2. Iron so what you think about the SC on 93 and Gibson SS Side Exhaust
I should be doing great b/n 2K-4K RPM with no WOT restriction and 91 program

3. Thanks all for the input so far:goodjob::goodjob:

 

2. Iron so what you think about the SC on 93 and Gibson SS Side Exhaust
I should be doing great b/n 2K-4K RPM with no WOT restriction and 91 program/QUOTE]

I've read a few dyno number and the gibson aint all that great your better off going to a shop and getting a true dual set up if you want some more power. If you just have the exhaust your going to see some gains with 91/93 and a tuner you should really look into an intake to complete it because you need to add air as well.

 

It looks like Uprev is the way to go so far!

its just a bit more expensive, but if I can get stock, 91,93 and valet and have a spare for more aggressive 93 tune .... 700 is not that bad... do you pay extra for each tune or is it 700 for 5 tunes and 3 update total?

 

I also have 93 octane down here in my area of Texas, but about half of Texas doesn't see it either. Mostly West Texas and the south. But running between here and as far as Uvalde, I've seen 93.

I run 93 with the Cortex. I still think the Tow Performance gave the best results....

 

in new york we have 87, 89, and 93... only sunoco stations have 91... so i run 93 with the 91 octane performance tune w/ cortex tuner. i didn't realize most places didn't have 93!

and as far as running a higher octane than required, as someone else said it's just a waste of money. if will do nothing for performance, may keep your engine a little cleaner, but just throw some fuel additive every once in a while and that will do the same thing for A LOT cheaper. but if you're getting better mpg... all the power to you

 

running higher octane will not keep your engine any cleaner. gov. regulations do not change for each different grade therefore in almost all cases the different grades have the same amount of detergent. our engine stock does not need higher octane and will not do anything different with it.

if you google it and read for a total of 5 mins you will see and understand what higher octane is and what it means.

 

Some here clearly do not have a good understanding of why there are different grades of fuel available then.

- The higher octane fuels DO contain more additives, and detergents than lower octane, cheaper fuels. If you look on google, what it explains more than anything else is that fuel you buy from Citgo is like to be the same fuel that your local cumberland farms is selling.

One other thing to keep in mind - Companies like Shell, Sunoco, most of the additives that they use for there fuels are added AFTER the gas has been refined. So while the gas was refined at the same place, for some brands, the additives are added after the fact, especially for there higher grade fuels.

- fuels BURN differently depending on the engine, specifically depending on the combustion chamber design and compression ratio. The higher the compression, the higher the octane needs to be to resist pre-ignition. If there is pre-ignition, not only does the fuel burn before the piston peaks, the fuel does not burn completely. Likewise, in a low compression motor, using a higher octane fuel will result in the fuel not combusting completely.

Keep the following in mind -

High Octane fuels requier more compression to achieve ignition, but the burn is hotter and more powerful than a lower octane fuel.

Low Octane fuels requier less compression to achieve ignition and have a complete burn, but the resulting burn IS less powerful.

Remember, an Octane rating is also an energy content rating on the fuel. The harder it is to ignite the fuel, the hotter and more explosive it is when it does ignite (especially because of the conditions needed to make it iginite in the first place)

Please don't take this as being rude, but there is a lot of misinformation in this thread already that really needs to be cleared up. Feeling the difference, and argueing about the engine running cleaner is really like arguing with a chimp - it dumb and they don't speak the same language. Running cleaner and making more power has a lot more to do with the engine running as effeciently as possible than anything else. For our trucks, in my owners manual the recommended fuel grade is 91 - and it's because of the compression ratio. Sure, there is a knock sensor and the ECM will reduce timing to prevent the pre-ignition, and that is why most people feel a difference when running a lower grade of fuel in a vehicle that has a recommended higher grade fuel.

 

Please don't take this as being rude, but there is a lot of misinformation in this thread already that really needs to be cleared up. Feeling the difference, and argueing about the engine running cleaner is really like arguing with a chimp - it dumb and they don't speak the same language. Running cleaner and making more power has a lot more to do with the engine running as effeciently as possible than anything else. For our trucks, in my owners manual the recommended fuel grade is 91 - and it's because of the compression ratio. Sure, there is a knock sensor and the ECM will reduce timing to prevent the pre-ignition, and that is why most people feel a difference when running a lower grade of fuel in a vehicle that has a recommended higher grade fuel.

you speak the truth and your part of the first red quote. our engines ARE NOT high compression and do not REQUIRE higher octane. 9.8:1 is not a high compression engine. i had a ZZ4 350 SBC running FI and compression was 10:1 and it didnt require higher octane fuel. your not talkin high compression till you get up and over the 10.5:1 or even up into the 11:1 and up.

 

our manual honestly recommends 91 octane? i'm going to have to double check mine i guess. according to everywhere i've read, Nissan recommends 87 octane and the yota's recommend premium.... if thats the case then i understand the confusion 100%

EDIT:

wow!!! I stand corrected and sincerely apologize, ive misled myself this whole time!!

From the owners manual (i found on the nissanusa.com website)
NISSAN recommends the use of premium unleaded
gasoline with an octane rating of at least
91 AKI (Anti-Knock Index) number (Research
octane number 96). If unleaded premium gasoline
is not available, you may use unleaded regular
gasoline with an octane rating of at least 87 AKI
number (Research octane number 91), but you
may notice a decrease in performance.

 

- fuels BURN differently depending on the engine, specifically depending on the combustion chamber design and compression ratio. The higher the compression, the higher the octane needs to be to resist pre-ignition. If there is pre-ignition, not only does the fuel burn before the piston peaks, the fuel does not burn completely. Likewise, in a low compression motor, using a higher octane fuel will result in the fuel not combusting completely.


i agree o everything except you saying that it burns hotter. there is not more heat energy, according to everything i have read.

-n most of the U.S., regular gas has an octane rating of 87, midgrade gas is 89, and premium is 91 or 92. (Octane ratings are lower in the mountain west due to the effects of thin air on internal combustion.) Contrary to widespread belief, the octane rating doesn't indicate how much power the fuel delivers; all grades of gasoline contain roughly the same amount of heat energy. Rather, a higher octane rating means the fuel is less likely to cause your engine to knock or ping. Knock, also known as detonation, occurs when part of the fuel-air mixture in one or more of your car's cylinders ignites spontaneously due to compression, independent of the combustion initiated by the spark plug. (The ideal gas law tells us that a gas heats up when compressed.) Instead of a controlled burn, you get what amounts to an explosion--not a good thing for your engine. To avoid this, high-octane gas is formulated to burn slower than regular, making it less likely to ignite without benefit of spark.-striaght dope

 

So what accounts for which areas get 91 or 93 octane? We only get 91 here now, but years ago 93 was availalbe.

 

Well, maybe the gas companies figure san antonio is in the hill country. Dont know. Here in the general houston area all stations have 93 octane.

 

superchips might develop a 93 octane tune if there is enough interest. send a pm to scott@superchips

 

93 octane here

 

look up octane guys...

 

All we have around here is 87, 89 and 93, so I used 93 with the performance tune...:noworries: