# Model A Ford Engine for Aircraft

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#### spduffee

##### Well-Known Member
I would be interested in a Model A engine for a Pober Junior Ace but have a few basic questions. 1) Does this motor need to be greatly modified for aircraft use? It was used in the Piets often, which were built on budget parameters. If yes, what is involved in the operation? 2) Does it have adequate hp for an aircraft that typically uses a C-85 (for example)? 3) How much do the Model A's weigh in comparison to a C-85? 4) Are they reliable in aircraft applications? and 5) Are they readily available?

Thanks!

#### cluttonfred

##### Well-Known Member
HBA Supporter
You definitely need to take your question to the Pietenpol community where you will find the folks with most experience with Model A Ford aero conversions. That said, a quick look at the specs for the two suggests that this would not be a good match. The Pober will be substantially heavier and the side-by-side open cockpit will cause more drag compared to the slim, light, tandem Pietenpol. Piet' performance on the Ford is already "stately." If going down that road, you might want to consider the more powerful Model B four-cylinder and some "performance" modifications. Alternatively, you might look to something like a direct-drive V-6 or V-8 or a Corvair conversion.

#### revkev6

##### Well-Known Member
I would have to say a big fat heck no! to the Model A engine. the model A uses babbit bearings not inserts like every other modern engine since the 50's (chevy was one of the last to change over in the early 50's everyone else changed by the late 30's) The model A has the correct RPM range, it's a fairly large cubic inch engine but it's horribly unreliable even in a car, weighs a ton and makes 40hp stock. I would guess that a vw conversion would even be better than a model A. Model A engines were the SBC of their day. they were EVERYWHERE every mechanic and hobbyist knew them inside and out. Now they are pretty much just a footnote in history.

#### TFF

##### Well-Known Member
A friend built his Pete with a B model. The B is pressure lubricated where the A is splash. He also has 2-3 Model A cars so he had spares. He also cast his own high compression cylinder head for fun. He built 2 Petes at the same time, one with the B and one with a 80 hp Kinner radial. The Kinner had double the climb. The Ford engine weighs 3 times as much as a A-65/ C-85; thats weight that could be a passenger or fuel. A Corvair would be better and easier.

#### TFF

##### Well-Known Member
You have to remember, the A engine was used because the Depression. If you read an article the date it was written has much to do with how it applies. in the 50-60's 0-290 GPU engines use to cost $200 surplus vs$3000 for the certified version, but today surviving GPU engines have been converted and parts are scarce to the point that it is cheaper to use the certified one than convert a new one. Alternate engines require scrounging and personal ingenuity, sweat equity; you still have to pay with ability instead of money.

#### spduffee

##### Well-Known Member
Ok, glad I asked. I was going for the retro-authenticity look, but it's not really important. I'm comfortable with the C-85/C-90, do I'll stick with those, I guess. Thank you all for your quick replies!

#### cluttonfred

##### Well-Known Member
HBA Supporter
Ok, glad I asked. I was going for the retro-authenticity look, but it's not really important. I'm comfortable with the C-85/C-90, do I'll stick with those, I guess. Thank you all for your quick replies!
There's a nice Junior Ace with big motorcycle wheels and a Rotec radial that was featured in Sport Aviation and the Rotec R-2800 is very comparable to a C-85. It would also be an excellent air frame for a Corvair engine.

#### spduffee

##### Well-Known Member
That's the nicest Junior Ace I have seen and I love the radial and the spoke wheels. Rotec's are pretty pricey, though. But, by the time I finish the build I may have more money, or they may be available as rebuilts. I do plan on replicating the vintage wheels...just doesn't seem right to stick Cleveland 600x6's on a plane that looks like its 1920's father.

#### HarveyH

##### Member
Spduffee, I like your idea of using a Ford Model A motor for its vintage appeal as I'm doing the same thing for the same reason, except that I'm building a Pietenpol. I've already done quite a bit of research on the subject so let me clear up/correct some things: The stock Model A engine puts out 40hp stock but can be increased to 50 or more HP with a few mods (i.e. higher compression head, better cam, dual ignition, etc). The engine is also very reliable as more than 12,000 still-running Model A cars, and more than 50 Model A-powered Pietenpols can attest. Also, the dipper ("splash") oiling system and babbit bearings are satisfactory for the HP and RPMs that the A motor puts out. However, there are some mods required before the engine can be used in an airplane and one is the addition of tubing within the block to provide better oiling to the main bearings. The Model B engine already has the better oiling and also has larger crank journals and a factory-counterweighted crankshaft. It also puts out 45-50hp but the engine is slightly heavier so you won't see a whole lot of improved performance from the extra HP. By the way, kits are available to equip the Model A's crankshaft with counterweights. Also, the Model A/B motors are plentiful (although a little less so for the B) and new-production replacement parts are widely available due to the continuing popularity of the 1928-1930 Fords. HOWEVER, let's face facts: ANY two-place airplane with a Model A or B motor will be a single-seater in the summertime and not a whole lot better in the winter. The Model A engine installation looks vintage/archaic but you're not going to be giving many rides to another adult with anything more than 1/4 fuel. Also, insurance companies are more agreeable to insuring your project with an aviation-specific engine such as a 65 or 85hp Continental, as opposed to a converted 80 year old car motor. PM me if you're still interested in going with a Model A or B motor and I'll help you find the information you'll need. I also have a few e-mailable pictures of art deco-styled Continental-powered Piets that can serve as ideas for your "vintage-looking" Ace project. Harvey

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#### cluttonfred

##### Well-Known Member
HBA Supporter
Hey, don't be stingy, share those pics here, too in a smaller size! ;-)

#### HarveyH

##### Member
Here ya go. While these two Piets are Continental powered, I think you'll agree that the builders have done a fine job of keeping their modern engines from ruining their plane's vintage appearance. (If you're not familiar with the Piet's stock nose, both builders have continued the top line of the fuselage all the way to the propeller, thus giving a higher than normal cross section. The bottom curve of the lower fuselage was also arced gracefully up to the prop. By comparison, the standard Piet nose tapers non-elegantly from the firewall to the prop as if a giant snow cone was planted onto the firewall and the pointed tip cut off and replaced with a propeller.)

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#### spduffee

##### Well-Known Member
HarveyH,
I didn't see this until just now. These are awesome pics - thank you!

#### Pops

##### Well-Known Member
Log Member
Have 2 Piets on the field and 2 Piet project. All with Cont A-65 engines. Even very underpowered with the Cont 65's. I fly in formation with the 2 Piets cross county often and have to fly about 45-50% power to stay back with them and have 3 times the ROC in my little single place Super Cub homebuilt. And I am way to old, and fat to get in the front seat of a Piet.. But they are a fun airplane. Dan

#### starlord

##### New Member
does anybody know how much this engine weighs. I want to compare with other engines

#### Topaz

##### Super Moderator
Staff member
Log Member
Who?

(Sorry, I don't have the answer for which you're looking, but it had to be done. Awesome film. :gig: Welcome to the forums.)

#### starlord

##### New Member
does anybody know how much this engine weighs. I want to compare with other engines

The pietenpol has me interested, however I want to use today's engine not yesterdays engine.

Has anyone done anything with diesel?

#### Tiger Tim

##### Well-Known Member
The pietenpol has me interested, however I want to use today's engine not yesterdays engine.
But if it's being bolted up to yesterday's airframe maybe what you really want is tomorrow's engine. Wouldn't that average out to the airplane of today?

#### starlord

##### New Member
But if it's being bolted up to yesterday's airframe maybe what you really want is tomorrow's engine. Wouldn't that average out to the airplane of today?

#### TFF

##### Well-Known Member
A yesterday airplane with a today engine. A paradox of space and time.

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