Effect Of Fuel Distillation Curve On Power And Efficiency

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I'm looking for any information in regards how the distillation curve of a given fuel(s) effects the performance of the fuel. Pump fuel is tied to standards for certain evaporation points where as aftermarket "racing" fuels are not. For a comparison of what I'm referring to...

Pump Gas, 93 AKI, 10% ethanol
RON = 98
MON = 88
(R+M)/2 = 93
Spec. Gravity = 0.745
Oxygen = 3.7%
10% evap. = 121*F
50% evap. = 180*F
90% evap. = 325*F
Final BP = 403*F

VP C45
RON = 106
MON = 100
(R+M)/2 = 103
Spec. Gravity = 0.738
Oxygen = 13.6%
10% evap. = 118*F
50% evap. = 164*F
90% evap. = 217*F
Final BP = 326*F

Speaking in terms of a port-injected EFI, throttle body injected EFI, or carbureted engine where you have a wet intake port. What effect would a lower temperature distillation curve have on the performance of the fuel in terms of power and efficiency of complete burn?
 
RDY4WAR, since you're not including direct injected set ups, could the lower temperature of vaporization make the air fuel mixture vaporize quicker thus distribute more even through the intake manifold and ports? Which would give a more even air fuel ratio to each cylinder?
BTW do you know how VP is achieving the high oxygenated content of VP45? Almost 4 times higher than 10% ethanol pump gas is quite a lot.
 
RDY4WAR, since you're not including direct injected set ups, could the lower temperature of vaporization make the air fuel mixture vaporize quicker thus distribute more even through the intake manifold and ports? Which would give a more even air fuel ratio to each cylinder?
BTW do you know how VP is achieving the high oxygenated content of VP45? Almost 4 times higher than 10% ethanol pump gas is quite a lot.

For TB injection or carburetor, I think a fuel with a lower specific gravity and lower boiling point would vaporize easier in the plenum and help distribution of the fuel to each cylinder. However, I also think that comes at a price in terms of power as that vaporization means displacement of air in the intake tract by the fuel vapor. That's where port injection would come into play. I didn't include direct injection because I'm more concerned with this in terms of vaporization in the intake tract and in the cylinder during the compression stroke. DI takes out those variables.

A liquid will not burn so you don't want the fuel to be in big liquid droplets in the cylinder at the time of ignition. However, you don't want it vaporizing in the intake tract either. So in my mind, the ideal fuel would be one that is atomized well in the intake port, injected as close to the valve(s) as possible, and then fully vaporizes in the cylinder during the compression stroke after the intake valve closes and before spark ignition. That's my theory. However, I have no evidence that is correct. I want to get a better idea of what it means when looking at fuel distillation curves.

A VP rep wouldn't confirm the contents of the fuel (didn't expect them to), but considering the SpG, distillation, and stoich, I'm guessing it's probably a blend of ethanol and methanol used as oxygenates with TEL providing the octane.
 
Thanks for the reply RDY4WAR. I've learned a lot from your posts over the years.

I was thinking more than likely VP was adding some form of alcohol to get the oxygen levels they're at. And since VP doesn't put that information on their site, I'm guessing lots of people in the drag racing community don't really want to know. Yet VP clearly states it's a leaded fuel.

Something else I don't know but guessing to be the case is that in general most anything you buy new for a fuel system in the drag racing circles, will have some type of compatibility to alcohol fuels. Like carbs , fuel pumps, lines etc.
 
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