danielhv

danielhv

Well Known Member
Of course Im thinking way far ahead... but I always imagined a 180hp (or 200 if I strike it rich!) fuel injected engine... Long story short, a friend is letting me fly his cessna 150, and paying HALF the price per gallon for auto fuel is becoming a bad habbit of mine. To the point where I cringe paying $3.80/gal for 100LL!

So my question is did this play into your engine selection? From what I have read so far... the only way I can do mogas is to get a D rated Lyc. O-360. Lose the fuel injection, and be happy with about 170hp...
 
Daniel,

Definitely affected my choice. I got an 8.5 compression IO-360 Superior, which burns premium mogas. The state will refund my road use tax, so currently I'm paying maybe $2.90/gallon. With avgas around $4.50, and using 7 gal/hour, that translates to around $10/hour in savings. Buy two hours and get one free!

greg
 
I opted for the AeroSport IO-375. I don't plan to run auto gas but I wanted to make sure I had the option more so because of the uncertain future of 100LL.
 
Effected my choice

I got an aerosport O-360 wanting the option for mogas 8.5 compression. I dont know if I'll ever run mogas but I have the option.
 
engine choice

When I started looking for a "deal" on an engine, I would have jumped on the best deal as long as it would work in my -9A.

The "deal" turned out to be an o-320E2A 150 HP lyc. The fuel required is 80/87 so I think it'll run on regular mogas. 7:1 compression ratio.

As a matter of fact, I've been doing some ground testing using mogas. The engine seems to like it just fine.

With 100ll prices as high as they are, I'm not sorry I ended up with this engine.

Now I just need to figure out how to transport mogas to the airport:)

Dave
 
I have a mogas burning RV now but like most men I am always looking on to the next and best thing. If I build an -8 it will have a mogas burning engine. If my -4 engine needs to be redone it will remain a mogas burning engine.

It's easy to find a local place that sells relatively cheap avgas but odds are it won't be your home field and it sucks having to stop to get gas on your way home.
 
Stock Lyc IO-360 from Vans so I could run Mogas if needed but have no intentions of doing so at this time.
 
Daver said:
The "deal" turned out to be an o-320E2A 150 HP lyc. The fuel required is 80/87 so I think it'll run on regular mogas. 7:1 compression ratio.
Click to expand...

I have the same engine as Dave (but still in pieces) and was considering converting it to 160 HP (to match my used prop)... but that means the compression will be 8.5:1.

Will I be able to run mogas with that compression? It is about $1/gallon cheaper around here. As for ethanol, I've been able to confirm that my Andair gascolator, fuel selector don't mind it and I think the Facet pump and red cube will be OK too. That just leaves the engine driven pump and the carb itself....
 
Yes

The ability to burn lower octane fuel is primarily a function of the compression ratio and from the research I have done, 8.5:1 will allow for the use of the aforementioned premium MOGAS.

I'm surprised no one has mentioned this thread on the subject. After reading that and doing some research, I opted for ECi's equivalent of an O-360-A1A which includes 8.5:1 pistons.

In addition, electronic ignition will allow you to fine tune your timing to match the fuel and engine combination, within limits. If you have 9+:1 pistons, you may not be able to tune your engine to MOGAS satisfactorily.
 
danielhv said:
So my question is did this play into your engine selection? From what I have read so far... the only way I can do mogas is to get a D rated Lyc. O-360. Lose the fuel injection, and be happy with about 170hp...
Click to expand...

I have a Percision Airmotive Silverhawk Ex injection system and per the documentation it has no problem with mogas.
 
Daver said:
Now I just need to figure out how to transport mogas to the airport:)

Dave
Click to expand...

Problem solved! Dual filtration, precise metering gage, 100 gallons so you can legally road the trailer to the airport in most states. Carrying & lifting 6 gallon cans is a PITA, dangerous, messy, and strains my back! Filters changed once a year, hoses replaced every two years or so.

fuel_tank.JPG


I save over $100 every time I fill it up. So far I have put over 6,000 gallons of fuel through this system.
 
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Ditto on the IO-375

This Aero Sport Power engine is good with mogas at 8:1 - 195 HP and a bit lighter than the big (expensive!) angle valve.

And better yet......it's actually on a truck headed for Iowa!! I'm ready to hang it upon arrival :D
 
Wow!

Larry - that's the neatest fuel transportation system I've seen.

I guess I'm going to have to build one!

Thanks for posting the picture!

Dave
 
No. I have 9.5:1 compression. Filling with five gallon cans is a pain and of questionable safety (or I am paranoid). Plus on trips how often do you find auto gas at airports?

100LL is not going away anytime soon. The replacement will be around 100 octane if not 100. Cost unknown since the replacement may not exist today.

Keeping your options open to use auto gas is not unwise. I may be the one regretting my piston choice someday in the future.

Larry, what did that fuel hauling system cost? I assume that to the right of the fuel filters is an electric pump. Can you keep it in your hangar legally?
 
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I did similar to Larry. Harbor Freight trailer cost about $200 and I found a fuel tank in guccidude's hangar (free!). Electric pump about $150 on ebay. Old battery to run it (free) and a bit of construction and ... done!

gimp2x - Nevada (and probably lots of other states) has a form that you fill out and return along with the receipts. They send you a check for the road use tax. This is done by a lot of contractors. Doesn't work well for boats, motorcycles etc. because I think the minimum refund is on 200 gallons and it would be hard to burn 200 gallons in a motorcycle.

cheers,
greg
 
I've seldom seen mogas available at the airports I land at, throughout the mountain west................so I suppose it doesn't matter. I don't enjoy puttering around my local field, therefor a mogas tank wouldn't do much good either. Besides, I like the smell, color, and longevity of 100LL over that of stinky mogas.... :D

L.Adamson --- RV6A
 
I have a 260hp lycoming with 8.5:1 pistons. I went that route not only because of the mogas deal, but also because I figure that the EPA is going to do something with 100LL, and because I didn't want any extra stress on the case, heads, etc.

Given how the local governments have added ethanol to the fuel without a care in the world about the problems it causes, I wouldn't be surprised if the EPA does something equally stupid with 100LL. 8.5 compression gives me some flexibility in the fuel system without loosing a ton of performance.

My plan for fuel when I first start flying is to get a 300gal tank, mount it in the bed of my truck, and go up to the fuel distributor, who offers a good discount on 100L when you buy more than 100 gallons. So I'll probably mix 150 gallons of 100LL with 150 gallons of 90 mogas which will be very safe for the engine, at a pretty good price, and it will provide some lead for the valve train while not enough to foul plugs.

Once I'm flying I'll probably upgrade to electric ignition at some point which will make things even better.

This is in a bearhawk which is gravity fed. If I was building an RV I would absolutely go the dual electric fuel pump route that frankh talks about. That would git rid of the vapor lock issues and make an RV able to run on ethanol mogas. Not that I would want to run that fuel, but the more options you have the better.

schu
 
Daver said:
The "deal" turned out to be an o-320E2A 150 HP lyc. The fuel required is 80/87 so I think it'll run on regular mogas. 7:1 compression ratio.

As a matter of fact, I've been doing some ground testing using mogas. The engine seems to like it just fine.
Click to expand...

Same exact engine in my Cherokee 140 (pic in my avatar). I have the autofuel STC for it and it runs on 87 octane unleaded just fine, although when I burn mogas, I generally use 91 octane premium unleaded. When run on mogas, the spark plugs stay *much* cleaner, and so does the oil too. With only 7:1 compression, this engine would probably run fine on any flammable hydrocarbon liquid substance that you could ignite with a spark plug.
 
I've got the O-320 E2A as well. And yes, fuel was a consideration for the purchase. I'll run the 7:1 cylinders until in need of an overhaul then throw on a 8.5:1 when the time comes if I deem it necessary. RV-7
 
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