Higher Octane + water injection question

[ChiGGz]

I was wondering if higher octane gas will give you more Power, or simply allows you to create more power. I hear people telling me the feel a world of difference when running 94 as opposed to 91. These are NA civics btw. Is there really a difference in power? It does burn more hot right? Or is the power difference simply the fact that the timing is advanced more due to higher octane.

My next question is if i run Water/Alc injection, can I safely resort to 91 Octane and still get the same performance boost? I'm thinking that if I can, then the injection system might pay off for itself after a year or two.

 

[Low Impedance]

unless the car is turbocharged or high compression, or otherwise modified with timing, you should use what the manufacturer says to use. sounds like a case of "butt dyno". on a turbo dsm id find the highest stuff you can (the car takes premium anyway) going lower makes lower preformance and kills the mileage you get on the gas. im lucky, in ohio there are stations with 100 octane

 

[Low Impedance]

and going higher than 94 isnt really cheap

 

[2gGSX]

Don't forget higher octane will kill the catalytic converter though. You should run premium but I would suggest only running higher then 94 at the track.

Could you expound on that statement? I've never read anything about higher octane unleaded damaging any cats or O2 sensors.

 

[Tsi2nr]

Only leaded racegas will kill your o2 sensors and cats. You can go as high as 104 octane and still be unleaded, but it is pretty darn expensive. Whenever you go to a normal gas staion all the gas is unleaded. But leaded race gas eats away at any o2 sensor and cats within a shortmanner of time.

 

[SBstar]

Could you expound on that statement? I've never read anything about higher octane unleaded damaging any cats or O2 sensors.

Thats what it says in the Dodge Ram owners manual. I suppose they could be mistaken.

 

[VanIsleDSM]

From what I've read in the past and makes sense to me, lower octane fuel is actually more explosive, more powerful, the cost of that is it's more unstable, and more prone to pre-ignition.. higher octane fuel has a slower burning flame front and is harder to ignite, that's why you can run more timing.. higher boost.. more compression.. and those capabilities far outway the probably negligible difference in the faster burn of lower octane.. for an n/a civic that doesn't push low octane gas near it's limit you might aswell use it, it'll probably burn a little hotter and make a little more power... and yeah depending on your setup you can use water/alk injection to surpress knock and mimic a higher octane but why not use 94 and the water/alk injection for more goodness?

so in plain words no, higher octane doesn't 'give' you more power.. it allows you to make more, it actually 'gives' you less.

 

[fourreGsixty3]

The higher the octane the cleaner and more fully it burns. The higher the octane the more boost you will be able to run without knock, it is a knock supresant, also you can run a bit leaner with higher octane gas then pump. Also water/meth injecton kits will one raise the octane count, the water will cool the intake charge, and the combination will clean up carbon deposits, and keep the cyl. walls clean...well as clean as they could be.

and going higher than 94 isnt really cheap

Going with 91 and meth injection will raise the octane count to around 96 or 97, and that isnt that expensive, because in the long run it allows you to run 91 octane, and save on the higher gas prices.
Also the water in the meth/water solution will soak up the heat, or some of the heat from the intake temp. charge and this will allow for more boost to be made with no knock. The meth/water injection kit will slow spool a few hundred rpm's, but you wont really notice it, this is because hotter EGTs the quicker spool, and since the intake charge will be cooler, the EGTs will be cooler thus a tiny bit slower spool. If you would like to learn more on this subject look here>http://www.dsmtuners.com/forums/showthread.php?t=240274, post #6 is where it gets good. And here>>>http://www.dsmtuners.com/forums/showthread.php?t=239585, this one is basing nitrous vs meth injection.

Dustin

 

[Defiant]

The higher the octane the cleaner and more fully it burns.

On the contrary: higher octane fuels leave more residue because of having more additives and less "gas" in the mix. Burning is a by-product of tuning, which higher octane allows you to set to higher levels. Getting more power still requires burning more fuel.

 

[LaserRSTAWD]

In my experience, premium gas is much better, and on a side note me/my parents owned a 96 DODGE caravan that had 250k on it before I sold it. It NEVER seen any thing but premium, and it was still fairly powerful for what it was(it would beat the 95+ ESi's)