GC to GCA conversion

[vintageair]

I know a guy who knows a guy who wants to put an O-320 on his O-290 powered 7GC

Now I've gone over all the details, The GC and the GCA are identical in every way per the TC, right down to having the same prop. The problem is that there were only a handful of GCA's built and there was never a service letter published for conversion of the GC to the 150hp powerplant.

So what I need is either a copy of a 337 or field approval to help with this submission. I know it's been done at least a few times just by looking at the 7GC database.

TIA - Paul

[Al Hatz]

The FAA registry shows only 50 Champion 7GC's with 7 in Alaska. I'd start by contacting those people and see if any were converted then get the paperwork from either them or the FAA.

[Captgrumps]

Years ago I had a 7GCA with a O320 (150 hp). Came from the factory that way.

Doug

[7GC]

I put an O-320 in my 7GC last year, 160 hp. I have a 337, if I could figure out how to get it uploaded.

Biggest advantage (in addition to getting rid of orphan engine) is rate of climb significantly improved.

[vintageair]

If you could scan it and email a copy to me that would be great. If you'd rather just send me a copy by regular mail that would work too. I've sent you my addresses by private message. This will help a great deal in getting approval. Thanks.

Paul