Homebrew "Race Fuel"

[RDY4WAR]

I'm wanting to get everyone's thoughts on blending 93 AKI non-ethanol pump gas with a blend of methanol and nitromethane. The blend ratio would be 9 gallons of gasoline to 1 gallon of 50/50 methanol/nitromethane blend. (VP Nitro 50-50) The use of this is a max effort NA drag racing engine that rules stipulate the fuel must be 90% gasoline. (free reign otherwise)

Here's my calculations of the effect of this blend. Now I know this may not be the actual result from the blend as different components of the fuel will act in different ways when blended. But, this should at least be ballpark.

BTU/lb of air
Gasoline = 1274
Methanol = 1328
Nitromethane = 2049

Stoichiometric Air/Fuel Ratio
Gasoline = 14.7
Methanol = 6.47
Nitromethane = 1.70

Specific Gravity
Gasoline = 0.745
Methanol = 0.795
Nitromethane = 1.139

Blend Ratio
Gasoline = 90%
Methanol = 5%
Nitromethane = 5%

Oxygen Content
Gasoline = 0%
Methanol = 49%
Nitromethane = 52%

Ballpark Blended Properties
Btu/lb of air = 1316
Stoich AFR = 13.64
Specific Gravity = 0.767
Oxygen Content = 5%

The questions I have are about blending and storage.

Will the methanol / nitromethane blend fully blend with the gasoline?

Could this be blended ahead of time and stored in a sealed container for a few months before use?

The initial idea was to blend 8-10% nitropropane or propylene oxide but those are pretty much impossible to get right now so I'm looking down this path. Any input is appreciated.

 

[sk_pete]

iirc, old race fuel was almost pure toluene, very high octane rating.
but needed to be preheated.

 

[RDY4WAR]

iirc, old race fuel was almost pure toluene, very high octane rating.
but needed to be preheated.

I want to avoid toluene and xylene since they are difficult to vaporize and burn efficiently without a lot of heat input. It's good in boosted engines because you have plenty of heat, which is why turbo F1 engines ran it a lot in the 1980s. A mild NA engine like I have would have trouble vaporizing it and burning it completely.

 

[Surestick]

iirc, old race fuel was almost pure toluene, very high octane rating.
but needed to be preheated.

That was the F1 turbo era. I believe they had a coolant > fuel heat exchanger to get the fuel to something like 70C so it would vaporise when injected.

Adding toluene to pump gas will increase its octane but too much would obviously lead to problems getting it to vaporise.

 

[Bullet]

I'm sure it's somewhere, but where does one even buy nitromethane? I've never seen it for sale.

 

[RDY4WAR]

I'm sure it's somewhere, but where does one even buy nitromethane? I've never seen it for sale.

Nitromethane Fuel: VP Nitro 50-50 | VP Racing Fuels

VP Nitro 50-50 fuel is blended with 50% nitromethane and 50% methanol. VP has been Makin' Power!® for nearly 50 years. Trust the fuel experts.

vpracingfuels.com

 

[thastinger]

Nitromethane will sit on the bottom of gasoline. You're going to have to break out your chemistry set and take a look at nitropropane.

 

[RDY4WAR]

Nitromethane will sit on the bottom of gasoline. You're going to have to break out your chemistry set and take a look at nitropropane.

I've been trying to source nitropropane for weeks with no luck. It's always been difficult to get but the pandemic has made it next to impossible.

If my theory is correct, the methanol will act as a co-solvent to blend the gasoline and nitromethane. I've been searching for verification of that. I'm supposed to get a call this evening about that subject.

 

[thastinger]

I've been trying to source nitropropane for weeks with no luck. It's always been difficult to get but the pandemic has made it next to impossible.

If my theory is correct, the methanol will act as a co-solvent to blend the gasoline and nitromethane. I've been searching for verification of that. I'm supposed to get a call this evening about that subject.

Will be interesting to see if there is enough "binder" in the methanol.
I'm not sure if you can even source some of the binders used back in the day and even if you could, I'm not sure I would want to be behind that exhaust pipe.