I am running 30 percent nitro and 11 percent oil, I want to increase my oil percentage 2 percent, total of 13 percent. How much oil (ounces) do I have to add to one gallon of fuel? I am not sure but I come up with 2.5 oz, is this correct?Are there any fuel specialist out there?

Using a prog called "Glowcalc" (glow fuel volume ratios):

Methanol 59% = 0,59 US gallon = 75,52 US fluid Oz
Nitro 30% = 0,30 US gallon = 38,40 US fluid Oz
Oil 11% = 0,11 US gallon = 14,08 US fluid Oz
Total 100%

Methanol 59% = 0,59 US gallon = 75,52 US fluid Oz
Nitro 30% = 0,30 US gallon = 38,40 US fluid Oz
Oil 13% = 0,13 US gallon = 16,64 US fluid Oz
Total 102%


Difference = 2,56
So you were correct

Thank you, I really was not sure of the amount,again thanks.

Ahhhh so much easier with metric

You can't have a bottle with 102% fuel in it!

If you only add some oil, the methanol and nitro percent will drop.

1 gallon = 3,79 liter (l).
59% methanol = 3,79 * 0,59 = 2,2361 l.
30% nitro = 3,79 * 0,30 = 1,137 l.
11% oil = 3,79 * 0,11 = 0,4169 l.

Raise the total volume with 2,3%:
3,79 * 1,023 = 3,87717
13% of that volume is:
3,87717 * 0,13 = 0,50403
Oil you'll have to add:
0,50403 - 0,4169 = 0,08713 liter oil = 2,9462158 US fluid ounces

New percents:
Methanol = (2,2361 * 100) / 3,87717 = 57,67%
Nitro = (1,137 * 100) / 3,87717 = 29,33%
Oil = (0,50403 * 100) / 3,87717 = 13,00%

What oil will you add?


I bought 12 gallons of 16% fuel last year for close to nothing. To transform it to 25% nitro and still have the same oil percent, I'll have to add both nitro and oil.


Cheers

on +/- 4 liter of fuel adding 2% oil it is just 40cc, you can calculate a lot but adding such an amount of oil will come close to 2% more oil....

yes it is all greek to me. I am adding 2.5oz of oil to an already premixed gallon of fuel a total volume of 100% adding 2.5oz of oil increases the total volume of fluid to 1ga.2.5oz or 130.5 fl.oz. in which adds up to 102% of fluid. The oil I am adding is Blendzall 2cycle racing castor lubricant. If I wanted to make my gallon at 30%nitro,13%oil I would use less methanol 57%

why do you want soo much oil ? adding oil just forces you to run a leaner mixture to get crisp throttle...a lower oil allows you to run a richer mixture and still keep crispy throttle response.....Also more oil will make the engine run hotter.....Now for breakin I can see adding oil...But for racing 13% is too much IMHO, and in the end wont do your engine much good if you tune for performance.... thats my story and I'm sticking to it !

i heard the old rule of thumb is anything over 10% is a waste. and i would think it would gum the motor up and create way more heat

Ok you guys are right. I ran it the other day and did not have to tune the motor, it ran pretty good but it did run 15*hotter so about 245-250 degrees. I just wanted to ad (blendzall) to my fuel. I guess I will run 30%nitro w/9%oil and add 2.5 oz.of castor oil(blendzall) That would make it 11% oil. I am just experimenting with the oil. By the way I am running the OS .21XZB engine.

could be wrong but a well know engine guru told me anything over 8% is overkill

I wonder what Rolo Tomassi has to say about the % of oil?

you'll need less oil if you run 30% nitro compared to e.g. 25% nitro. That's a fact

Why buy 30/9% fuel and add extra oil, when you just can buy 130/1% fuel??

I am just experimenting with oil. Byrons fuels are available in 30% nitro 11% oil. That is what I run, I did notice the engine ran better at 13% oil but 15degrees hotter.

I think adding a very small ammount of castor oil is good. I wouldn't put 2 oz's in it. Probably 1/2 ounce. Most fuels with under 10% are pushing it. I like the 25% nitro 11% oil myself with a small ammount of castor just to make it perfect. especially during break in..I mix the 20% 16% with the 25% 11% sometimes. That works awesome for breakin......