Model A vs Corvair engine weight

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jdb1930
Posts: 3
Joined: Tue Sep 05, 2017 11:49 am

Model A vs Corvair engine weight

Post by jdb1930 »

What is the weight difference between the Model A engine and a Corvair conversion? And do most build the fuselage with the added 6in if powering with a corvair engine?
habickford
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Joined: Fri Mar 03, 2017 9:58 am

Re: Model A vs Corvair engine weight

Post by habickford »

Corvair engine weight is about 220lbs. The "A" is about 242lbs plus cooling system of 23lbs and weight of coolant 22lbs for a total of 287lbs. An aluminum head for the 'A' cuts about 15 lbs from the weight. Remember those are typical weights and individual installations can vary.

More to the point BHP did the long fuselage for the Corvair and A-65 installations for proper CG as they were both lighter than the "A".

Harold
jdb1930
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Joined: Tue Sep 05, 2017 11:49 am

Re: Model A vs Corvair engine weight

Post by jdb1930 »

I had no idea the A was that much heavier.

I read that some people used the short fuse for the corvair when using a fuel tank behind the firewall. Is it still better to go with the longer fuse if using a fuel tank like that?
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taildrags
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Re: Model A vs Corvair engine weight

Post by taildrags »

When you think about it, the Ford A engine is a big monolithic hunk of iron with some holes in it while the Corvair is a hollow aluminum casting with heavily finned head castings and finned iron cylinders. The Ford is basically solid iron, the Corvair is basically hollow or finned aluminum.

I have not heard much discussion about the short fuselage, but I have heard about builders making their vertical stabilizer and rudder larger to provide more control authority in yaw. It would seem to me that the short fuselage would reduce rudder and vertical stab effectiveness since it would have a shorter moment arm over which to work.
habickford
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Joined: Fri Mar 03, 2017 9:58 am

Re: Model A vs Corvair engine weight

Post by habickford »

Just follow what BHP drew up. The long fuse seems to taxi better. The fuse tank is typically 5 gallons so 30 lbs.plus weight of tank. With a normal wing tank that is 17 gallons total. Then you can figure about 2 hours at 5gph and be good on fuel.

On our project the deeper Riblett airfoil should accommodate a 15 gallon wing tank.
jdb1930
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Joined: Tue Sep 05, 2017 11:49 am

Re: Model A vs Corvair engine weight

Post by jdb1930 »

5 gal in fuse tank? All of the things I have been reading was 16gal in fuse tank.
habickford
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Joined: Fri Mar 03, 2017 9:58 am

Re: Model A vs Corvair engine weight

Post by habickford »

Again, you can configure what fits. I was referring to the original BPH Corvair setup where he placed a fuel tank in the area used by the magneto/drive on the Ford 'A'. As an example our 1941 Chief uses a 17 gallon fuse tank. The drawings for our side by side Piet project include a 16 gallon fuel tank. A 19 gallon fuse tank for a Pitts is common. W&B along with safety and fuel flow are the main issues.
at7000ft
Posts: 36
Joined: Mon Mar 06, 2017 3:06 pm

Re: Model A vs Corvair engine weight

Post by at7000ft »

Have a long fuse with a Corvair and a 17 gal tank behind the firewall. Plenty of control authority with standard size tail components.

Rick H
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Richard Roller
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Location: Olathe, Ks.

Re: Model A vs Corvair engine weight

Post by Richard Roller »

I did the weight and balance for Ken Perkin's Piet N34KP. It has a model A Ford installed. When originally built it was very tail heavy. Ken didn't want to move the wing so I did the figures to find out how far we would have to move the engine to get inside the aft c.g. limit. We weighed the Piet with a set of race car electronic scales. After getting the weight (658 lbs.) we removed the engine and weighed it with the prop and oil and added 16 lbs. to the weight for the water. The engine is modified per the plans, has a aluminum head and a slick 4000 series mag driven off the crank. It has an Ole Fahlin 76x44 prop. With prop, oil, and water the engine weighed 256.3 lbs.
17_orange_piet.jpg
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