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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