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ACRO E-mail Archive Thread: [Acro] RE: Certificated to Experimental?

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ACRO E-mail Archive Thread: [Acro] RE: Certificated to Experimental?


Thread: [Acro] RE: Certificated to Experimental?

Message: [Acro] RE: Certificated to Experimental?

Follow-Up To: ACRO Email list (for List Members only)

From: "Andrew Boyd" <aboyd at>

Date: Sun, 01 Dec 2002 17:47:07 UTC


Is there anyone who has successfully pushed a 330hp hotrod 
overhaul of a parallel-valve 540 through a 337 on a certified aircraft?

My understanding is that for about the same dollars as a factory
engine, you can get 70 extra horsepower.  Hard to ignore a 25%
horsepower increase.

Has anyone installed a Whirlwind propeller on a certified
aircraft with a 337?


Tom Adams said:

WHY NOT just stay in Standard category with the use of a Form 337. I can't speak for other  type a/c but I have a Pitts S1-T that is still in Standard and I have made a lot of modifications with the 337. Should work with other types of a/c. I admit, you do have to jump through a BUNCH of hoops for the feds but I have found it worthwhile. 

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