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Tony Woolner
January 5th 04, 12:09 PM
Anyone know about AMR@D propeller tip mods and Vgs mod for a Cherokee
140. Pros and cons?

January 5th 04, 05:20 PM
Tony Woolner > wrote:
: Anyone know about AMR@D propeller tip mods and Vgs mod for a Cherokee
: 140. Pros and cons?

I have a friend with a 140/160 with both mods. The prop tip definately
required re-pitching, and if the VSI is accurate it climbs as well as my Cherokee 180.
Not sure about cruise/top speed increases, but his plane is definately a "strong"
climber. (Need to qualify the term "strong," and recall that this is, after all, a
Cherokee).

WRT the VG's, they seem to do what they claim (except the speed). Both his
140/160 and my 180 went from barely flying at 60 mph IAS w/ full flaps to being able to
hang it on the prop at 45-50 mph when not too heavy. Significantly lowered the sink
rate on final (especially when a little slow at 80 mph or so, 2 notches flaps). Maybe
gained 100 fpm climb (from the reduced sink at slow speeds). Didn't affect cruise
measurably (no increase nor decrease). My gut reaction is that it help most at lighter
weights, but I don't fly close to gross very often to verify that.

Hope that helps.
-Cory

--
************************************************** ***********************
* The prime directive of Linux: *
* - learn what you don't know, *
* - teach what you do. *
* (Just my 20 USm$) *
************************************************** ***********************

Jay Honeck
January 5th 04, 07:23 PM
> I have a friend with a 140/160 with both mods. The prop tip definately
> required re-pitching, and if the VSI is accurate it climbs as well as my
Cherokee 180.
> Not sure about cruise/top speed increases, but his plane is definately a
"strong"
> climber. (Need to qualify the term "strong," and recall that this is,
after all, a
> Cherokee).

Does AMR&D have two different prop mods?

A friend bought his prop from them, and it's billed as a "speed prop" --
which it achieves at the expense of climb.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

January 5th 04, 07:45 PM
Jay Honeck > wrote:
: Does AMR&D have two different prop mods?

: A friend bought his prop from them, and it's billed as a "speed prop" --
: which it achieves at the expense of climb.
: --

I think they've only got one prop mod, but it's touchy to get the pitch correct
after that. In my friend's case, he did the prop mod, prop re-pitch, high-compression
mod on the engine (160hp), and an overhaul all at once. He said it would initially
exceed redline in a Vy climb! After the re-pitch, he gained about 5 mph in cruise, and
climbs out at 2400 rpm.

With any fixed-pitch prop on a semi-streamlined plane, it's a compromise
between static RPM and thrust (and consequently climb) vs. cruise speed/economy. Only
in a "mono-speed" plane (takeoff 90, cruise 90, land 90) can a fixed prop be "optimal."

-Cory


--
************************************************** ***********************
* The prime directive of Linux: *
* - learn what you don't know, *
* - teach what you do. *
* (Just my 20 USm$) *
************************************************** ***********************

Jay Masino
January 5th 04, 07:58 PM
Jay Honeck > wrote:
> Does AMR&D have two different prop mods?

No.

> A friend bought his prop from them, and it's billed as a "speed prop" --
> which it achieves at the expense of climb.

That sounds like just a re-pitching.

--- Jay



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__!__
Jay and Teresa Masino ___(_)___
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Jay Masino
January 5th 04, 08:09 PM
Tony Woolner > wrote:
> Anyone know about AMR@D propeller tip mods and Vgs mod for a Cherokee
> 140. Pros and cons?

I have the prop tip mod, the VGs, the 160HP upgrade, Metco tips, the full
Knots2U kit, and the Powerflow exhaust. All together, my 140 went from a
115 mph plane to a 135+ mph plane, and it climbs a lot better than a stock
140.

Without some very precise time trials (which I wasn't really willing to
do), it's difficult to say how much each piece contributed. That said, it
"seemed" that the VGs dropped the stall speed a few MPH, and increased
the cruise by a few. A lot of people scoff at this, and I don't blame
them. All I can say is that the TOTAL amount I've gained appears to be
real (based of years of flying, with GPS, in both configurations).

--- Jay



--
__!__
Jay and Teresa Masino ___(_)___
http://www2.ari.net/jmasino/ ! ! !

Checkout http://www.oc-adolfos.com/
for the best Italian food in Ocean City, MD and...
Checkout http://www.brolow.com/ for authentic Blues music on Delmarva

Aaron Coolidge
January 6th 04, 03:29 AM
Jay Masino > wrote:
: Tony Woolner > wrote:
:> Anyone know about AMR@D propeller tip mods and Vgs mod for a Cherokee
:> 140. Pros and cons?

I recently ferried a Cherokee 140 with the 160HP mod and the prop tip mod
from K1B9 (Mansfield, MA) to KPGD (Punta Gorda, FL). This airplane has
no other mods, and about 200 hours SMOH. I got a TAS of about 102 to 105
Knots running 70% power (2475 RPM at 6500' DA). This seems several
knots faster than the other 140's I have flown. The airplane has a much
better climb rate than the other 140's I have flown, almost 1000 FPM on
cool days (50 deg F surface temps).

The biggest difference between this airplane and my Cherokee 180 (that I
noticed) was the acceleration on the runway. Oh, and it should be flown
a little slower on final.

: I have the prop tip mod, the VGs, the 160HP upgrade, Metco tips, the full
: Knots2U kit, and the Powerflow exhaust. All together, my 140 went from a
: 115 mph plane to a 135+ mph plane, and it climbs a lot better than a stock
: 140.

Wow, Jay, that's a tremendous improvement. My (almost) stock Cherokee 180
does about 137 MPH, 70% power (I have Met-Co-Aire tips). If you could even
estimate the value that each addition gave I would be grateful. Seems
like if I added all of the mods I would have a 300+ knot Cherokee.

I called AMRD about the VG kit for my Cherokee 180. He said "it's in the
STC listing, but it doesn't make any noticeable difference on a 180".
I haven't inquired about any of the other mods, from AMRD, K2U, or anywhere.

I can already pull over redline in level flight, and the Powerflow
system isn't available for my airplane (I have the dual-muffler system),
so I'm not worried if you can't estimate anything from that. I have a climb
prop (the only one available for my airplane - can't be repitched according
to the TCDS), and it really does climb!

: Without some very precise time trials (which I wasn't really willing to
: do), it's difficult to say how much each piece contributed. That said, it
: "seemed" that the VGs dropped the stall speed a few MPH, and increased
: the cruise by a few. A lot of people scoff at this, and I don't blame
: them. All I can say is that the TOTAL amount I've gained appears to be
: real (based of years of flying, with GPS, in both configurations).

Again, even some estimates would be of value to me. Thanks.
--
Aaron Coolidge (N9376J)

Aaron Coolidge
January 7th 04, 01:21 AM
Mike Spera > wrote:

:>. lots of stuff snipped
:> Again, even some estimates would be of value to me. Thanks.

: Estimates???: About 1000 dollars per knot.

: Value: in the eye of the beholder.

Mike, that's what I thought, and that's why I have an unmodified airplane.
I guess that I'll take that $10K that I don't have to spend and deposit it
into the "Mooney fund".

--
Aaron Coolidge (N9376J)

Jay Masino
January 7th 04, 12:20 PM
Aaron Coolidge > wrote:
> : Estimates???: About 1000 dollars per knot.
> : Value: in the eye of the beholder.

> Mike, that's what I thought, and that's why I have an unmodified airplane.
> I guess that I'll take that $10K that I don't have to spend and deposit it
> into the "Mooney fund".

You're right. If all you want is speed, you should keep contributing to
your Mooney fund. A lot of my motivation was just the fun of doing it.
Spending a $1000 every other year or so, for a few modifications, was just
fun. As it turned out, the TOTAL gain was pretty impressive, but that was
secondary. Actually, increasing the climb rate was more important ro me
than speed. Most of the mods were very reasonably priced (except the PFS
exhaust), and I bet I spend less for all the mods than it would have cost
to buy a 180 (for comparable performance). Anyway, the biggest bang for
your buck is definitely the Knots2U kit. I suspect I gained 8-10 mph from
that alone. All the other mods were a few mph each.

--- Jay



--
__!__
Jay and Teresa Masino ___(_)___
http://www2.ari.net/jmasino/ ! ! !

Checkout http://www.oc-adolfos.com/
for the best Italian food in Ocean City, MD and...
Checkout http://www.brolow.com/ for authentic Blues music on Delmarva

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