VP111 vs C12. Is the 1 octane point the only difference?

[snowfix]

I ended up with a barrel of each of these fuels. The motor octane difference is VP111 is 107 octane, and C12 is 108 octane.

Besides the obvious motor octane difference of 1 point, can I treat these fuels the same when i'm blending it with pump for my T-Nytro?


Based on the calculator I'm planning to do a 50-50 blend for 18 lbs boost at 6000 feet with 9.5 to 1 compression and powderlites recommended timing changes. That's what I ran on my Apex last year with similar changes without any issue

 

[Boyko]

I can not see why not at 50/50 mix it should only bring the octain down 1/2 point.

Look at the weight of the barrles marked on the tag I think the 111 is heaver, on a carb system it could make a difference.

 

[HURRICANE]

Look at the specific gravity of the two fuels.Thats important for the burn rate of the fuel.There may be a conciderable diffrence in the specific gravity

 

[mbarryracing]

Look at the specific gravity of the two fuels.Thats important for the burn rate of the fuel.There may be a conciderable diffrence in the specific gravity

X2

Affects AFR's as well.

 

[snowfix]

Look at the specific gravity of the two fuels.Thats important for the burn rate of the fuel.There may be a conciderable diffrence in the specific gravity

Specific Gravity: .720-.735 @ 60° F for VP111


Specific Gravity: .717 at 60° F for C12


Is that close?

 

[HURRICANE]

that's close enough

 

[BigDog05]

If you determine that you need around 102 octane for around 12 psi of boost, what specific gravity number are you looking for?

Example: VP red is 105 motor octane, with a specific gravity of .730-.745.

Sunoco 110 racing is 105 motor octane, with a specific gravity of .728.

Both are readily available and approx. the same price.

Do you want the highest specific gravity, or do you want to stay above a certain specific gravity like .715 for example? Thanks