Getting Started in 2013, Part #19, Cylinder Heads

Builders,

There is a lot of small detailed information that goes into heads. But first, it is good to look at the big picture. What kind of heads do you want?  From a practical perspective, the top of the line are FalconMachine.net’s heads.  This is the product of “Mark from Falcon” or “Mark Petz” Or “M.P.” You could actually use Mark’s legal last name Petniunas. I have known Mark for about 10 years and I barely know how to spell his last name, and I know 5 ways to mispronounce it. Linguistics aside, they guy knows Corvair flight heads like no one else, he has produced well over 100 pairs of magnificent heads, and the work is beyond reproach. If you send him your cores, he will rework them, including welding on the intake pipes, for $1,270.  Theoretically you could spend more elsewhere, but you can’t find better work.

Is $1,270 a lot? Consider this: A guy with an O-200 buying 4 cylinder assemblies is going to spend about $3,800. If you add the cost of a set of 2700 cc forged pistons and rings and rebored cylinders to the cost of the heads, you end up with an apples to apples comparison of $3,800 to the Corvair’s price of $1,965.  Yes, the top half of a Corvair, built with the finest stuff, costs 52% of the same parts for an O-200. Even the top half of a 3,000 cc Corvair is only 82% of the cost of putting a top end on a Continental. (BTW, the 65 hp Continentals cost the same.)

Every time I show math like this at an Oshkosh forum, some guy will hold up his hand and say “There is an O-200 in the flymart for $5,000, and I’ll bet it is just as good as a $7,500 Corvair, and I won’t have to build it.” … Where do I start? First, if a person’s goal is to not have to build things, than what are they looking at experimental aircraft for? I like most things about O-200s except for the new owners of Continental (the communist Chinese), but the chances that the example in the flymart possesses and will demonstrate all of the qualities associated with the design are very low. Note the guy’s words carefully: “I’ll Bet”. If you are new to aviation, you might think that the man’s wager is $5,000. Heck, the guy saying this probably thinks that is what he has riding on his guess of wishful thinking. In reality, he is actually wagering far more; in escalating order of importance, the $5,000, his airframe, his safety, and his passengers’ safety. It is a lot to bet on a guess that your flymart engine has good internals.

There are two types of mindsets at work here: The flymart buyer is inherently lazy, and he doesn’t want to know what’s inside his engine. For him ignorance is bliss. On the other hand, if you are the kind of builder who wants to know what you’re doing, what you have and can count on, and where you stand, then you are always going to choose to count on your own learning and craftsmanship. You are not going to have to “bet,” you know what you have, and this is bliss to thinking people.

 

Above, Mark stands with his $38K Dynamometer in his shop Outside Madison WI. Note race car in background. No one should take fashion advice from this man, but is commentary on Cylinder heads is followed by many motor heads.

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The lowest cost short block with a 5th bearing we looked at in the chart was an Allen Able with 2700 cc cylinders, the AA-1 engine configuration. This cost $3,057. Add a set of Falcon heads and you are looking at $4,357. This is not a complete engine, but it is well past the halfway point and any builder getting this far already knows a lot more about aircraft engines than he did going in. The most important point: Such an engine is not made of worn parts or salvaged stuff like a flymart engine. Such an engine isn’t even how Corvairs have typically been built in years past. This is a first class engine with a 5th bearing, nitrided crank, ARP rod bolts, forged pistons, stainless valves, an excellent cam, new lifters, bearings seals and gaskets. This is something very real and high quality, produced by a set of hands and a mind that will be the master of the machine, not its servant nor victim.

The most expensive long block on the chart is the Davie Dog 3,000 cc engine, the DD-5.  Adding a set of Falcon heads to its price brings the total to $7740. That isn’t cheap, but for that price you are putting together some very fine metal. I am pretty sure no other popular alternative engine has a U.S. made crankshaft in it. Think that one over for a minute. We were the country that invented powered flight, flew the Atlantic, finished WWII with it and then went to the moon, and today, the selection of  non-certified engines at Oshkosh is almost exclusively made elsewhere. When did that become OK? Yes, virtually every VW engine sold in the past 20 years has had a Chinese crank in it. Jab, Rotax, UL, and Honda based engines are all made by people far away. I have never owned an imported car in my life, and I don’t have any desire to own an imported motor in any airplane I am building. That said, I think I can effectively demonstrate to any person with an open mind that there are very good mechanical reasons and a long proven history behind the Corvair that make it the engine of choice even for a person who didn’t care where it was made.

If you search the words “Falcon Heads” in the search box of our main page, www.Flycorvair.com, you will find many long stories describing them in detail. In the past few years there have been only small refinements in Mark’s heads. Every set now comes with the previously optional exhaust rotators,  and the final machine work on the seats is now done on ultra expensive state of the art machinery. Other than theses touches, it’s much the same. As a builder, do you have to have Falcon heads? No, but learn two lessons from others without paying for the education personally. First, I have seen a number of people drop $750 for trash work and junk valves thinking they saved $500 over Mark’s price. In some cases they just flushed $750 and had their core heads mortally wounded in the process. They didn’t save anything, they lost. Second, a great number of people who started out with local machine shop heads later converted to Falcon heads. It you are going to get there eventually, it’s less expensive to draw a straight line to the destination rather than having a several hundred dollar way point. -ww

Head group (1500)

1500- Pair of heads with seats and guides

1501- Valve spring set

1502- Retainer set for intakes and keepers

1503- Exhaust valve rotators and keepers

1504- Intake valves -6-

1505- Valve seals

1506- Exhaust valves -6-

1507- Exhaust stacks -6-

1508- Welded on intake pipes

About William Wynne
I have been continuously building, testing and flying Corvair engines since 1989. Information, parts and components that we developed and tested are now flying on several hundred Corvair powered aircraft. I earned a Bachelor of Science in Professional Aeronautics and an A&P license from Embry-Riddle Aeronautical University, and have a proven 20 year track record of effectively teaching homebuilders how to create and fly their own Corvair powered planes. Much of this is chronicled at www.FlyCorvair.com and in more than 50 magazine articles.

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