X-Mozilla-Keys:                                                                                 
charles.harbert@fmglobal.com wrote:

Paul, Jeff's right on a lot of this. I think I got a good deal on this because
Mark did a lot of work for me ($2K) (intake manifold, water inlet, etc.), plus I
worked directly with him in his shop laying out where everything was to go.
Mostly, he did the machining and welding, but it was a collaboration. He's a
pilot and a A&P, plus a certified A/C welder. Really does beautiful work.
Because he gets an unbelievable deal on the waste Inconel, he didn't charge me
much for it which may be unique to him. I could ask him what he'd charge to
build another one if anybody wants to know. Also, you'll pay another $250 for
all the flanges and gaskets for the block, wastegate, and turbo.

He's also right that I had to find a way to get a large wastegate into a very
tight area. I sacrificed some efficiency advantage to achieve a low weight,
functional design. I felt that most of the disadvantage of having the wastegate
near the #3 exhaust was for an automobile application where engine rpms go up
and down continuously and for "turbo lag". As I understand it, the wastegate
only has to reduce exhaust pressure effectively, and so far it seems to be doing
that.  As I wrote earlier, I wanted to keep the noise down so I routed the
wastegate into the turbo exhaust. I also wanted to keep the exposed surface area
of the exhaust manifold to a minimum to avoid heating all the surrounding areas
(block, intake, cowls, etc). All of the exhaust has to be sheilded.

The overhang was also a concern, but the inconel manifold is very strong and it
is only about 4 inches wide which was the least width Mark could make it. I'll
add a brace from the block to help support the turbo, but there's been no sign
of any distortion in14 hrs of running under load.

I think that Jeff's log type design is superior to mine, and I wish it had been
available earlier, as I'd have bought one.

Chuck what do you mean "30" out of 40"" available?

Paul Lamar
 
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