wrote in message
...
Matt Barrow wrote:
: Bonanzas primarily. One really nice thing is a TN makes lower altitudes
: practical; no need to go to 12-15K feet

: Beryl d'Shannon (sp) and TurboAlley are the two biggies with STC's.

: I've had a TN IO-550 for just under 1700 hours now and it's been nothing
: short of amazing. So far, none of the "horror stories" that Doug
Paterson is
: worried about. Thing is, a TN unit will run about $30K up to $45K
installed.

Like I said, impractical to add yourself. Question though... a buddy of
mine
used to have a Cessna 310 Riley Rocket. In addition to the speed mods on
the airframe
(bondo-buggy as he called it), it had *manual* wastegates.

ICK!!!!

I would think that those
would be preferable, unless the wastegate controller on the aftermarket
ones are
clever. From the looks of the ones on TurboAlley, it sounds like they are
"hands-off"
turbo...

Yup...a popoff valve will release at about 30.0-31.5" MP. Nothing to control
or worry about...just fly.
No chance to overboost.

http://www.avweb.com/news/columns/182102-1.html (Those Firebreathing
Turbo's - part 1) Read all six...really good diagrams and illustrations.

Are they the same as the stock, suck-dick Piper turbo Arrow setup? In
other
words, controlling the wastgate to always making maximum boost and then
throttling
with the throttle plate?

Those are the kinds of "simple," yet horribly stupid design choices that
lead
to premature engine/turbo wear. No point in pumping/heating 12000' air to
31" if
you're only going to run 23 squared. Anyone know?

Or if you're seldom going over 8-10000 feet.

I take it Doug is in Colorado Springs (6100-6800). He's worse than me
(5600'), but I have 14000 foot mountains to the East, and 10-12000 footers
West of me and we're down in a valley (a REALLY BIG one, but a valley
nonetheless).

It can certainly be done without a turbo, but the Springs during
June/July/August is going to be a thrill.


--
Matt
---------------------
Matthew W. Barrow
Site-Fill Homes, LLC.
Montrose, CO