[VNeBLOB42]

I have been doing some research but still not sure if this is good or bad. from what i understand its not. but just wanted to get some feedback if anyone has done this.

In California, well at least in the valley i can't find anything other than 91 octane and 100 octane at 76 gas stations. So for me to get the best tune from my COBB AP i wanted run 93 octane.

So i guess is this OK and do these mixtures look right??


i have found these mixtures on the Internet.

http://www.300cforums.com/forums/att...91octlarge.gif



also this on another forum had this for a 17 gal. tank,


1 gal race/16 gal 91= 91.5
2 gal race/15 gal 91= 92
3 gal race/14 gal 91 = 92.5
4 gal race/13 gal 91 = 93.11
5 gal race/12 gal 91 = 93.6
6 gal race/11 gal 91 = 94.17
7 gal race/10 gal 91 = 94.7
8 gal race/9 gal 91 = 95.2
9 gal race/8 gal 91 = 95.7
10 gal race/7 gal 91 = 96.2
11 gal race/6 gal 91 = 96.8
12 gal race/5 gal 91 = 97.3
13 gal race/4 gal 91 = 97.8
14 gal race/3 gal 91 = 98.4
15 gal race/2 gal 91 = 98.94
16 gal race/1 gal 91 = 99.47
17 gal race/0 gal 91 = 100

[rgbimmer]

sounds legit, but curious to hear from someone who knows.

[Luky]

I created a spreadsheet where you can put in the price of each and how many gallons and it will calculate the octane and the final cost per gallon. Can I post an excel spreadsheet on here? It will also give you the cost and octane for mixing in Toluene (114 octane) which I have been looking for to see if it would be cheaper to use for boosting 91 octane to 94 or so ... at about $14 to $15 a gal its a wash with $8 gal 100 oct race gas. If you can find it for less though...

[VNeBLOB42]

Originally Posted by Luky

I created a spreadsheet where you can put in the price of each and how many gallons and it will calculate the octane and the final cost per gallon. Can I post an excel spreadsheet on here? It will also give you the cost and octane for mixing in Toluene (114 octane) which I have been looking for to see if it would be cheaper to use for boosting 91 octane to 94 or so ... at about $14 to $15 a gal its a wash with $8 gal 100 oct race gas. If you can find it for less though...

Yes, go to "go advanced" when you reply or just the standard post there will be a plus symbol to add attachments. Click on that and it will enable you upload from your pc.

[07_335i_AW]

Those octane levels look correct. The way to calculate it is:

Race gas oct. rating x Gallons of octane + pump gas oct.rating x gallons of octane.

Total from above / (divided by) total gallons in tank = octane rating

soo for .. 1 gal race/16 gal 91= 91.5 broken down is 100x1 + 91x16 = 100+1456= 1556 /17 = 91.5

Hope this helps

[BEAR-AvHistory]

Originally Posted by 07_335i_AW

Those octane levels look correct. The way to calculate it is:

Race gas oct. rating x Gallons of octane + pump gas oct.rating x gallons of octane.

Total from above / (divided by) total gallons in tank = octane rating

soo for .. 1 gal race/16 gal 91= 91.5 broken down is 100x1 + 91x16 = 100+1456= 1556 /17 = 91.5

Hope this helps

+1 I use the same system to bring NC standard 93 up to 95 octane with a 93/100 mix

[Wires]

That seems like waaaaayyy too much work to get a couple extra ponies from 91 octane.

[Kolyan2k]

or u can just drive up here and I will sell you some 93 and a great discount price

[VNeBLOB42]

Originally Posted by 07_335i_AW

Those octane levels look correct. The way to calculate it is:

Race gas oct. rating x Gallons of octane + pump gas oct.rating x gallons of octane.

Total from above / (divided by) total gallons in tank = octane rating

soo for .. 1 gal race/16 gal 91= 91.5 broken down is 100x1 + 91x16 = 100+1456= 1556 /17 = 91.5

Hope this helps

Awesome!

thanks for the reply. the formula will save me some time.

[VNeBLOB42]

Originally Posted by Wires

That seems like waaaaayyy too much work to get a couple extra ponies from 91 octane.

Yes its a pain in the ass, but the pre-set MAPs for JB4 and COBB are specific to 93 octane. (if you want a lil more hp) so its best to use 93 when using those MAPs.

once you put this formula in excel its a not a problem.

[VNeBLOB42]

As based above,

here is the formula in excel.

just fill in the tank capacity and ensure your rating octane = the total tank capacity..

So if your E92 tank is 15.9(+- 16)

it will take 12 gallons of 91
&
4 gallons of 100 octane (4+12=16)

93.25 Total Octane give or take...

[07_335i_AW]

Originally Posted by VNeBLOB42

Awesome!

thanks for the reply. the formula will save me some time.

No prob. The hard part is tying to determine how much fuel you have left in your tank to start the calculations...