Al Gietzen wrote:

When I decided to do a custom engine installation, I knew I was taking on
some serious challenges, and that it would lengthen the time to completion
of the airplane.  But I didn't anticipate the difficulties and delays in
getting components from vendors.  For what it's worth, here's my experience.

ENGINE

Based on availability, price and engine building experience, I chose to get
my 20B from Atkins Aviation (David Atkins).  David quoted the entire
package, which included the rebuilt engine, induction system (with custom
lightweight intake manifold, EFI/EI), custom inconel exhaust system, custom
oil pan, etc. So, although I had reservations on the custom parts, I decided
it would save me considerable time to have him do the full engine package;
I'd do the cooling systems, mount, etc.

I placed the order late November, 1999; with delivery estimated for end on
January.

The rebuilding of the engine was completed by late January. That much was on
schedule; looked good.  The only point of concern was that they had
installed the 9 : 1 compression turbo rotors instead of the 9.7 : 1 rotors
Mazda used for normally aspirated engines.  Skip (Dave's partner) makes the
argument that, based on his experience, the lower compression can actually
give better power in the high RPM range.  Physics aside, I'll withhold
judgment pending some dyno testing.

At that time, none of the custom items had been started.  For the next five
months work on these proceeded very slowly and frustration grew.  And being
1200 miles away didn't help.   Finally, by late May, the mount, the oil pan
and the exhaust manifold/muffler were completed (these were done by Mark
Sedickas).  Although I had been told that the intake manifold was nearly
finished in both March and April, I was now told that the vendor was not
able to do the job.   I informed Atkins that I was coming to get whatever
was done the first weekend in June.  On June 1st I was told that everything
was ready to pick up, including the intake manifold.

Skipping the details, the results were that for various major or minor
reasons, none of the parts fit, and the intake manifold was unusable.
Although it is understandable that errors can be made when making one-off
parts, it is not understandable that no dimensional checks or trial fitup
had been done. With more weeks of making changes and corrections I think I
have it complete, except for the intake manifold, which is under
constrcution.

Your mileage may vary.

RADIATOR AND OIL COOLER

I went out to a number of vendors (Fluidyne, Ron Davis racing, Griffin,
Positech, TEMP, Inc.) for quotes on my design for these items.  I learned
pretty quickly that to most vendors "custom" means their standard cores and
standard end tanks, just made to different radiator dimensions.  My needs
were more custom; and TEMP and Griffin were the only ones to work through
with me to make what I wanted.  Although I think the computed performance
(pressure drops, heat rejection) given to me by Griffin is probably
optimistic, their performance data was better and prices considerably lower
than TEMP's.

The problem at Griffin is that one guy's, one order, seems to get lost
there.  I did finally (after nearly four months) get the radiator; and it is
a very nice piece of work and reasonably priced.

On the oil cooler; after working out the design with their engineer (this
took weeks); I went through the sales folks to get the quote.  Checking a
week later; it would be done "in a few days".  Checking another two weeks
later, they'd lost it.  So after about a month I did finally have the quote.
I liked it and ordered the cooler.  It would be done "in about a week".  Two
weeks later, they couldn't find any record of my order.  You get the
picture.  I'm still waiting for my oil cooler.

If you can, get a more 'standard' design; or be very patient and check every
week.  I'm told that ordering a custom version from Griffin works better is
you order through one of their dealers.

Oh; and if you can, get custom parts made close to home where you can check
on them; about one day's ride; by horseback.

Al

Some very good points Al. It jibes with my experience getting parts
made for my fifth wheel systems over the years. I am actively looking
for local suppliers for the several parts that I or Tracy will offer.
It has taken me two months to get the six port intake flanges.

BTW I am thinking of starting a list of local suppliers around the 
country. If any of you guys out there have had good luck with fabricators
or suppliers let me know, send their address and phone number and I will 
add them to the list.

Paul Lamar

 
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