mixing race fuel
 

i need to get fuel that is is atleast 102 to 105 octane, but all that is avalable is 110 octane

the question is how much 93 octane would i have to mix with 110 to make 102 - 105 octane?

Most of the time you looking at (R+M)/2 for the octane you are getting. Thats (R)esearch Octane+(M)otor Octane/2. With out some serious testing to see how the two fuels mix and what they are made of to get those ratings it would impossible for Joe Blow on the street to get the definite answer.

I hope your running a turbo looking for that octane, it will be wasted on an NA. If you are running a turbo the extra octane wont hurt and you won't be saving that much money trying to get a mix just right with the 93 stuff. Then the whole problem of consistancy between batches comes up if you tune the engine to use the fuel you mix up.

Just Average the numbers. It will give you a close number.

ex: (7gal x 93oct) + ( 9gal x 110oct) / 16gal = 102.56

Motor Octane is the number you want to go by

well its not for my rx7 its a friend who has a race gas tune on a Xcal II

thanks for the help i've got it figured out now