race fuel and pump premium

[eli]

what ratio should be pump premium and race fuel ,i feeling nobody is buying premium around here and i dont want to be the first buying old gas ,and thinking some race gas would be good till maybe some fresh gas is delivered this summer.my motors are pump gas 93

[Dave Strong]

PM me your e-mail addy have formula but its on Works and can't post it.

Dave

[h2oskiier30]

Easiest way to figure octane when blending two different octane fuels is:

1. (Octane of fuel #1) X (# of gallons of fuel #1) = X
2. (Octane of fuel #2) X (# of gallons of fuel #2) = Y
3. X + Y = Z
4. Dividing Z by the total number of gallons of both fuels gives you your total octane number.

For example, let's say you have 10 gallons of 93 octane, and 5 gallons of 112 octane race gas.

1. 93 X 10 = 930
2. 112 X 5 = 560
3. 930 + 560 = 1490
4. 1490 / 15 = 99.33

So, the total octane of the mixture would be just over 99.

[Jay Smith]

Its according to the cranking compression of the engine this "mix" is trying to support without detonating ..

Load, prop pitch, engine mods, timing @ WOT , geographic location , and cranking compression ALL become important factors in the equation when determining safe octane ratios...

Jay;)

[Forkin' Crazy]

Easiest way to figure octane when blending two different octane fuels is:

1. (Octane of fuel #1) X (# of gallons of fuel #1) = X
2. (Octane of fuel #2) X (# of gallons of fuel #2) = Y
3. X + Y = Z
4. Dividing Z by the total number of gallons of both fuels gives you your total octane number.

For example, let's say you have 10 gallons of 93 octane, and 5 gallons of 112 octane race gas.

1. 93 X 10 = 930
2. 112 X 5 = 560
3. 930 + 560 = 1490
4. 1490 / 15 = 99.33

So, the total octane of the mixture would be just over 99.

That makes sense and should work. And I have the same fear Eli. I had a motor that was running on the boarder line. Ran it all day with premium. Filled it the next from a different station and didn't go a full mile before I popped it. Better safe than sorry. I have a gravity feed 350 gallon tank I am planning to have some AV gas put in. :D

[Dave Strong]

Its according to the cranking compression of the engine this "mix" is trying to support without detonating ..

Load, prop pitch, engine mods, timing @ WOT , geographic location , and cranking compression ALL become important factors in the equation when determining safe octane ratios...

Jay;)


Altitude is the killer for me, I'm safe here at 3000' but if go somewhere lower have to add more VP. Race fuel is not a cheap deal anymore, bud is no longer VP guy. Looks like ACES is going to be the way to fly now, no airport here.

Dave

[Jay Smith]

Dave ,

You'd be amazed how backing the WOT timing down just 2 degrees on a trip to lower altitudes would be and create a huge safety factory in your engine's tune..

Jay

[eli]

have 10 gal of 112 being delivered to get me thru the weekend ,jay i think with race gas and pump 93, 4 gal 93 to 1 gal 112, timing can be left alone after that i,m going to back timing 2 degrees. without race gas 93 combo, were at 1300 ft above sea level,thanks

[Dave Strong]

Dave ,

You'd be amazed how backing the WOT timing down just 2 degrees on a trip to lower altitudes would be and create a huge safety factory in your engine's tune..

Jay



Will keep that in mind, its kinda cool to up the octane to compensate for the altitude drop. Its just like having a different engine for a weekend.


Dave

[Lockjaw]

Just get someone to give you some lead tetraethyl, and dont' worry about race gas. LOL!!

[eli]

have 8 qts of real tethraethyl lead i use on frequently ,and i am not really sure it does increase octaine, what about carbon from lead around the rings,,dave i could not open your email

[eli]

dave ,i could not open the email with the formula .

[phil blomquist]

I could not open it either. Would really like to know a proven mixture great thread!

[jay j]

For what its worth, i run a steel sleeve motor(laser inj) from mother mercury and race with ODBA in the 800 ft outlaw series. I run around 180lbs compression with 26cc chamber heads and 27 dergrees timing.
I run 1 gal of 110 sunoco with 2 gal of pump 93. turned motor over 9grand many times and still safe, but I am draggin and not puttin a big wheel and running for miles at wot. the shorts props will not load the motor like a big one and cause as much heat. hope it helps.

[Dave Strong]

Eli and Phil, if you click on lines in row d&f and put in values for octaine and amounts the total fuel and final octaine should change to what you will end up with. It is baisicly the same formula as h20skiier30 posted.

Dave

[phil blomquist]

thanks dave ill try it again

[Dave Strong]

thanks dave ill try it again

For some reason the number color is yellow and hard to see.


Dave