What type of fule would a modified suburu engine to aviation use?

Question

i have seen a few. examples.

http://www.youtube.com/watch?v=bU2elPTJyqA&feature=related - the dodgy tripple turbo

http://www.GlasairProject.com

Answer 1

In the old days, it wasn't unusual for cleaver folks to drain the hose of The Av-Gas trucks into their car tank.  Cheap fuel.  However Av-Gas, at least in the 60's lacked a lubricating agent found in Automotive fuels.  If done to often or in too high a ratio, the valves would burn out.

Vapor Lock is caused by the fuel turning into gas before it enters the fuel pump so the engine starves out.  This used to be relatively common crossing the desert, especially with Ford Flat Heads.  I don't know if that would be a problem at the speeds and cooler air of altitudes but it's something you should check out, especially if you intend to operate in warm climates.  I believe you would have to change out the intake manifold but I don't know if that incorporates the solution.  You might try asking at one of these sites,

http://www.eggenfellneraircraft.com/Egge...

http://www.zenithair.com/zodiac/6-photo4...

http://www.sdsefi.com/aircraft.html

Answer 2

The real question is not the fuel type, but the mounting and gearing of the engine. You would want to gear the engine so that  maximum rpms give you only 2500rpm to the prop.

You would also need to redo the weight and balance to position the engine correctly along the length of the aircraft.

Last thing, you would want to do it in a better suited aircraft. An aircraft like the 150 is excessively heavy for carrying just two people. Most 40hp ultralights can match a c150 in speed and payload. I would put it in something like a Hummel bird from Hummel aviation (which is about $5000-7000 a kit). Its a sweet little 250lb plane that doesnt look like you made it out of lunch trays and art supplies.

You would need at least a private pilots license to operate it as an experimental.

Answer 3

I don't know much about modifying engines, but if you're planning on doing something like that, contact your local FAA FSDO (Flight Standards District Office) to get their assistance on registration, type certificates, etc.  They'll walk you through the process and make sure you don't do anything illegal.  Local FSDO contact information can be found on FAA.gov

Answer 4

MoGas.  87 octaine or higher.  No ethanol!

Answer 5

I don't know why you would want to modify a car engine, when purpose- built aircraft engines are available at some pretty low prices. One such manufacturer here in Australia is JABIRU. They build a range of engines from 4 to 8 cylinder, the 4 cyl being 2.2 Litre (134 cu. Ins), and right now is on special @ $A 12,900.00. Ideal for C150, in fact you may need to add ballast or remount further forward, they are very light. Jabiru also build aircraft. Look them up!

Answer 6

You'd still want to use aviation gasoline.

At altitude vapor lock becomes a greater possibility

with regular auto gas, and 'having the noise stop`

while aloft is not pleasant.

Answer 7

The Sub engine would still take normal automotive fuel. Don't know if it could be run on 100LL or not.