110 octane

[EZWood]

So i went down to my local napa, bought five gallons of 110 octane put it in on E. more power, better response. filled it up the rest of the way with 91, lost some of the power and response. what im wondering is what is the limit where its a waste for octane level? Anyone have an opinion on this?

[Silverdub]

Interesting but at the actual price of fuel i might stick to 91 if u dont mimd

[fenton]

Our cars aren't going to gain much more over and above 94 octane. If good 93 to 94 octane is used the car should run the maximum timing it is capable of.

Sent from my Galaxy Nexus using Tapatalk 2

[SeattleJeremy]

The stuff you bought, does it says "Unleaded"? If not, the lead in the fuel will destroy your catalytic converters.

[xwd]

What that guy said. Sounds like more of a placebo affect than a thing else. If the cars are like other Subarus there are Self adjusting maps which get more agressive without knock events happening by just dump

[DIE1000DEATHS]

Yes, higher octane = less energy. Thus if you're not already getting any knock and such, the car isn't going to default to exceedingly aggressive timing or a/f ratios to take advantage of the anti-knock potential of the gas...

[DIE1000DEATHS]

...Which will equal no added power if not potentially even a loss...

Sorry, getting used to posting w/tapatalk...

[jedibow]

http://www.ft86club.com/forums/showthread.php?t=9265

No, I didn't post this because it has the funniest quote I have ever read...

[EZWood]

Hmm, well the temperature here in the Phoenix metro area was in excess of 111 degrees Fahrenheit, and I'm sure the extra six gallons or so effected the weight of the car enough to change the readout of my butt-dyno.

[Jordo!]

Originally Posted by EZWood

So i went down to my local napa, bought five gallons of 110 octane put it in on E. more power, better response. filled it up the rest of the way with 91, lost some of the power and response. what im wondering is what is the limit where its a waste for octane level? Anyone have an opinion on this?

In the absence of tuning, or at least datalogging options (e.g., of ignition timing), you have no way of knowing what, if any, gains were made.

Put in on a dyno, first with 93, then reset ECU, then run with 100+, then post results.

Real Dyno > Butt Dyno

[Jordo!]

Originally Posted by DIE1000DEATHS

Yes, higher octane = less energy. Thus if you're not already getting any knock and such, the car isn't going to default to exceedingly aggressive timing or a/f ratios to take advantage of the anti-knock potential of the gas...

No, higher octane = less likely to autoignite.

You will still make the same torque burning the same amount of high octane petrol -- it still is stoichiometric at 14.7:1.

[GenkiElite]

Almost a complete waste of money on a stock car. This exact subjuct is already being discussed here and has been dicussed on every car forum on the internet since the begining of the internet and probably before that. This horse has been beatin for so lung we're just pounding on dust now.

[jedibow]

Originally Posted by Jordo!

In the absence of tuning, or at least datalogging options (e.g., of ignition timing), you have no way of knowing what, if any, gains were made.

Put in on a dyno, first with 93, then reset ECU, then run with 100+, then post results.

Real Dyno > Butt Dyno

I am the link ninja!

http://www.ft86club.com/forums/showthread.php?t=8691

for those that are too lazy to read...

Factory fresh datalogging...

[vividracing]

Run the lowest octane you can without knock! Otherwise you can foul plugs, o2 sensors, cats and so on. Octane boosters like to foul things as well.