Octane/ Fuel Mixing

[lmritter]

Greetings:

I have come to realize that we all are students AND all things are not as they first appear. Thus ... my question. I am currently using 91 octane fuel, the highest octane available in California ( generally ) My 2006 C2S 997 recommends 93 octane. I have recently discovered a gas station ( locally close at 8 miles ) that offers 100 octane racing fuel. Wishing to raise the octane rating in the fuel I use, is raising the octane to 93 or above as simple as averaging the gallons vs octane? OR??? Is there some other formula/ratio that must be used . IE: Does 4 gallons of 91 octane plus 4 gallons of 99 octane mixed yield 8 gallons of 95 octane. Thanks for the input.

Chromedome

2006 C2S , Carrara White, full sand beige leather, power/heated seats/ carrera classic wheels, self dimming , leather wrapped full funtion sports steering wheel etc.. my dream car

[RFM]

Racing fuel is not recommended for street cars because of different reasons. Belgian market Porsche's runs on 97 octane but we can get in some places 100 octane unleaded street fuel as well, the perceptible difference is only the price in this case. If you ever got serious engine trouble while using racing fuel , the warranty is lapsed, don't forget that.

[lmritter]

Racing fuel is not recommended for street cars because of different reasons. Belgian market Porsche's runs on 97 octane but we can get in some places 100 octane unleaded street fuel as well, the perceptible difference is only the price in this case. If you ever got serious engine trouble while using racing fuel , the warranty is lapsed, don't forget that.

Greetings:

Let me throw this out to all of you again. The product is called " Street Blaze " Street legal ( in the US ) 100 octane fuel.

Thanks

Chromedome

[Dave07997S]

Racing fuel is not recommended for street cars because of different reasons. Belgian market Porsche's runs on 97 octane but we can get in some places 100 octane unleaded street fuel as well, the perceptible difference is only the price in this case. If you ever got serious engine trouble while using racing fuel , the warranty is lapsed, don't forget that.

Greetings:

Let me throw this out to all of you again. The product is called " Street Blaze " Street legal ( in the US ) 100 octane fuel.

Thanks

Chromedome

Forget the previous post...if you can only get 91 octane like here in Cali blending 3-4 gallons of 100 octane will get you near the 93 octane Porsche normally recommends for the car. Here in Cali the crap 91 we get really isn't true 91 octane. I run 3 gallons of 105 F&L unleaded racing gas and this gets me close to 94 octane as I am burning this with the crap 91. You will notice a little more get up and go with the car via improved throttle response as the car will feel a little sharper.

Running above 93 octane will probably be counter-productive unless you have software that can take advantage of this. Keep in mind it's a diminishing return...after 93 octane even with software there really isn't that much more power to be had. With modern engines 93 octane can easily support a 12:1 compression ratio.

Oh and to answer your question..yes 4 gallons of 100 and 4 gallons of 91 will actually get you 95 octane..it does work that way. Here is a nice chart..

octane chart

Dave

Edited February 3, 2008 by Dave07997S

[lmritter]

Racing fuel is not recommended for street cars because of different reasons. Belgian market Porsche's runs on 97 octane but we can get in some places 100 octane unleaded street fuel as well, the perceptible difference is only the price in this case. If you ever got serious engine trouble while using racing fuel , the warranty is lapsed, don't forget that.

Greetings:

Let me throw this out to all of you again. The product is called " Street Blaze " Street legal ( in the US ) 100 octane fuel.

Thanks

Chromedome

Sir:

Thank you very much, great chart . AND I do agree with you. I put in 5 gallons of " Streetblaze 100 " ( Unleaded ) yesterday and topped off my tank to 16.9 gallons. After driving and mixing the fuel I noticed 2 issues. First , the car ran much smoother. It had more " pep " Secondly, it started immediately, not with the normal 2 to 3 cranks. Streetblaze is expensive, about $7.00 to $8.00 a gallon, but at 5 gallons per tankful and the few miles I put on my C2S , it is worth it. California gas is crap. A good friend of mine put some "streeblaze" in his WRX STI and the boost pressure max went from 15.7 to 16.8. He said there was a most definite smoothness and p[wer increase. He can remap his Ecu as desired, which is an issue I may look at after the warranty expires on my 2006 C2S. Again, Thanks

Chromedome

[mapoune]

Yeah, yeah, we have 98 here in France and 102 on the racing track ... Unplug your battery and all the procedure for ECU recalibration. To be honest no worth the spending.