Turbo Lance II opinions

On Mon, 22 Aug 2005 14:39:32 GMT, john smith wrote:

snip

An intercooler is a radiator that cools a gas (air) instead of a liquid.
When air is compressed (what a turbocharger does) it heats up. When a
gas is heated it wants to expand (return to an uncompressed state), so
you place an intercooler (or two) inline following the turbocharger and
before the engine air intake, to cool the heated, compressed air before
it enters the engine, providing cooler, more dense air to the engine.
Cooler dense air can absorb more heat than hotter dense air and provide
greater expansion and therefore more power.

Technically, an intercooler is a "radiator" placed between a
exhaust-driven turbine compressor and a mechanically-driven turbine
compressor (a la B-17). Your description of an aftercooler is spot-on.

You may not be familiar with the Turbo Lance/'Toga "intercooler"
installation. It is a relatively inefficient aftercooler installation
that has other very important benefits.

It changes the existing lower cowl design from a single common air
inlet which is shared between updraft cylinder cooling, induction air
supply, and oil cooling air cupply. The new lower cowl has separate
inlets for updraft cylinder cooling, induction air, and oil cooling,
as well as the aftercooler inlet.

Unfortunately, the outlet of the aftercooler heat exchanger is
exhausted into the pressure area for the updraft cylinder cooling.

The installation will drop operating CHT by approximately 40-60
degrees F, and operating oil temp by 20-40 degrees. Considering that
CHT can run 450 F and oil temp 220+F this is a very good thing.

I honestly cannot recall the typical induction air temp drop, but the
overall package works quite well. IMHO this is as much a result of
improved engine/oil cooling air flow as actual induction air cooling.

Personally, I would not consider operating a Turbo 'Toga/Lance without
this modification.

Regards;

TC

Personally, I would not consider operating a Turbo 'Toga/Lance without
this modification.

Well it seems that after reading all the articles mentioned on turbos and
your comments, my decision has come down to one aircraft with and one
without this intercooler mod.

I'm assuming this mod can be performed aftermarket. Do you happen to know
the cost of performing the mod?

The asking price difference right now between the two is about 20k. There
are some other factors going into that cost, but I need to be able to
justify the extra $$$.

On Tue, 23 Aug 2005 11:59:51 -0400, "John Doe"
wrote:

Well it seems that after reading all the articles mentioned on turbos and
your comments, my decision has come down to one aircraft with and one
without this intercooler mod.

I'm assuming this mod can be performed aftermarket. Do you happen to know
the cost of performing the mod?

The asking price difference right now between the two is about 20k. There
are some other factors going into that cost, but I need to be able to
justify the extra $$$.

10 years ago it was around $6500 + install. Only web reference I could
find for the kit says $7495 (no idea how old).

Unfortunately, other digging around on the 'net indicates that
Turboplus is not currently an operatiing GA entity. Found a post by a
guy that says he owns all the paperwork/assets and is looking for a
buyer.

Could call these guys, I guess:

http://www.barteltaviation.com/install.htm

Back to airplane shopping:

If I was looking at these aircraft, I would want to know EXACTLY how
much total time was on the exhaust components. Would NOT recommend
running any of them past recommended TBO. Anybody that tells you any
different has very likely never seen the results of a turbo lance/toga
exhaust failure/engine fire.

On a test flight, look/ask about typical oil temp/CHT indications in
cruise. If the engine has been operated for any period of time with an
oil temp over 210 or CHT over 450 (hard to tell, no numbers on factory
gauge) is likely to have cam spalling & accelerated e-valve guide
wear.

Don't ask me how I know this...

TC

wrote in message
...
On Tue, 23 Aug 2005 11:59:51 -0400, "John Doe"
wrote:

Well it seems that after reading all the articles mentioned on turbos and
your comments, my decision has come down to one aircraft with and one
without this intercooler mod.

I'm assuming this mod can be performed aftermarket. Do you happen to know
the cost of performing the mod?

The asking price difference right now between the two is about 20k. There
are some other factors going into that cost, but I need to be able to
justify the extra $$$.

10 years ago it was around $6500 + install. Only web reference I could
find for the kit says $7495 (no idea how old).

Unfortunately, other digging around on the 'net indicates that
Turboplus is not currently an operatiing GA entity. Found a post by a
guy that says he owns all the paperwork/assets and is looking for a
buyer.

Could call these guys, I guess:

http://www.barteltaviation.com/install.htm

Back to airplane shopping:

If I was looking at these aircraft, I would want to know EXACTLY how
much total time was on the exhaust components. Would NOT recommend
running any of them past recommended TBO. Anybody that tells you any
different has very likely never seen the results of a turbo lance/toga
exhaust failure/engine fire.

On a test flight, look/ask about typical oil temp/CHT indications in
cruise. If the engine has been operated for any period of time with an
oil temp over 210 or CHT over 450 (hard to tell, no numbers on factory
gauge) is likely to have cam spalling & accelerated e-valve guide
wear.

Don't ask me how I know this...

TC

TC,

Thanks. That's what I'm worried about. It only has an EGT gauge and
nothing to monitor CHT or TIT, etc.

Is there going to be problems getting parts for the turbo system ?

On Tue, 23 Aug 2005 20:19:14 -0400, "John Doe"
wrote:


TC,

Thanks. That's what I'm worried about. It only has an EGT gauge and
nothing to monitor CHT or TIT, etc.

Is there going to be problems getting parts for the turbo system ?

Honestly, have been out of the GA game for several years.
Historically, the exhaust components were available from Lycoming
(they are engine-specific, not airframe specific). Can't remember
having any issues finding an aircraft turbo overhauler that didn't
have the capabilities to do the turbo.

Also, bear in mind that unless things have changed, there is an
AD-mandated recurring 100 hr exhaust inspection (referencing a
Lycoming SB-499 I think). To do this inspection properly takes some
time, and will periodically require some on-condition parts
replacement.

TC