Power Flow Systems - First Impression

[Lawreston]

My Skyhawk was just ferried from 3B5 Twitchell's to IWI Wiscasset. Dale Twitchell landed a few minutes before I arrived by Buick, and he taxied to the hangars at the opposite end of the airport from my unit.

"Here; why don't you taxi her to the East side." I didn't have a headset with me, so I could imagine how loud it would be in the cockpit. Surprise!
When I started the 0-320 my first exclamation was, "It's so quiet," to which Dale responded, "I noticed that, too; much quieter than the stock exhaust system." And there we were, carrying on a casual conversation while taxiing, neither wearing a headset(no intercom; a Garmin GMA-340 is waiting to be installed with other avionics).

Dale: "I'm impressed; she was off the ground considerably before what is normal, and the VSI indicated 1200fpm, in a light breeze." NOTE:The fuel was light, he having added 8 gal. before departure.

So much for taxiing; I'm looking forward to flying with the new addition.
More, later.

HR

 

[Pilawt]

They really sound different on the outside, too. My dad has a 172N with an O-360 and Power-Flow. At the NWAAC Evergreen Fly-In a few years ago I looked up to see what kind of weird machine was making that funny purring sound, and was surprised to see it was my dad's 172 entering the pattern.

-- Pilawt

 

[Lance F]

Interesting to hear this about the 172 with a PowerFlow. I never measured it before and after with a decibel meter, but I believe my Mooney is louder with the PowerFlow than with stock.

 

[JRitt]

My 172N is quieter on the inside but louder on the outside.

 

[Paul Allen]

Interesting to hear this about the 172 with a PowerFlow. I never measured it before and after with a decibel meter, but I believe my Mooney is louder with the PowerFlow than with stock.

Lance,
Does the Power Flow do anything for your Mooney?

 

[Lawreston]

.... and here is my 2nd impression of the system. Today was my first flight in the Skyhawk I last piloted on March 14, 2004. It was, also, my first flight with a new CFI. From Wiscasset(70msl), Maine: Winds calm, visibility 10+, altimeter 30.43, and full tanks.

Rotation was at 60mph and occurred markedly prior to what has been customary on the same runway. Climbout was at 90mph and at about 1000msl I glanced at the VSI: slightly in excess of 1200fmp. I did four landings at Augusta, Maine. AUG sits atop a bluff. Departing Augusta into a moderate wind and en route to Wiscasset the VSI again indicated in excess of 1200fpm. I'm definitely going to like the Power Flow Systems benefits, based upon observations, thus far. An unsolicited observer asked if the plane had an engine upgrade, said question prompted by engine sound upon rotation and climb.

HR

 

[Richard]

Cool, Harley. I've flown different planes with powerflow exhaust systems but forget if a new set of performance numbers is in order for a plane so equipped.

 

[Dean]

My question is, was it worth the 4K price tag? I only know two guys who have the power flow system and they both agree that if their planes had'nt come with them, they would'nt spend the money. Not that big of difference. One is on a Mooney the other a 172.

 

[Lawreston]

My question is, was it worth the 4K price tag? I only know two guys who have the power flow system and they both agree that if their planes had'nt come with them, they would'nt spend the money. Not that big of difference. One is on a Mooney the other a 172.

Depends upon where one may be flying/departing, I'd say. My original home field was just over 1900' gravel over turf(see photos). Though I have the hangar 7.2nm from the photos which show trees at #14 and a lot of water just off #32, I'll be doing a lot of overnighters there during the summer. It's only 5.2sm from my house, and I'll have another vehicle there to drive home.

I landed/departed there today; and there's now a significant reduction in takeoff roll. Coupled with the increased rate of climb, seeing those trees further down is refreshing. No regret$.

HR (Photos are not from today, but May 15, 2005)

 

[Bill M.]

We have the 3rd generation power flow on our 77 skyhawk. Sounds better, climbs better, and gets better mileage. Someone said they thought it was louder outside and quieter inside. I agree and think it sounds a little "throatier" too. I have also noticed about a 200fpm increase in ROC all things being equal. Since I have much more time than money, I usually fly x-countries about 65% and have noticed about a gallon per hr. improvement in mileage between 7-8 GPH...I know...I should probably use a calender instead of an airspeed indicator.
We thought we were going to have to have the prop re-pitched, but turns out it had a "speed" prop instead of a "power prop" already.Another benefit is the heater and defroster work a whole lot better now. I recommend the power flow and think it was worth the $4500.

 

[Lawreston]

I'm with you, Bill. Mine is the latest version, with ceramic option. With 2.5 hours of flight time I've not had sufficient time to ascertain the fuel-burn changes. And during my first flight -- I in first flight with a new(to me) instructor -- there were a lot of slow flight, med. bank turns, steep turns, T & Gs; maneuvers not compatible with altitude cruising.
My A & P/Installer also indicated that repitching the cruise prop would not be necessary.

It was an interesting flight; no intercom, pending GMA-340 Audio Panel/Intercom installation early next month. CFI wore the headset and did traffic, I flew; hand signals/sign language was much in evidence. PFS can count me as an endorser.

HR

 

[ejensen]

My question is, was it worth the 4K price tag? I only know two guys who have the power flow system and they both agree that if their planes had'nt come with them, they would'nt spend the money. Not that big of difference. One is on a Mooney the other a 172.

I wouldn't go out and purchase outright. But if I needed to rebuild the exhaust anyway I'd consider that a subsidy and go for it on my M20F. Last time I redid the whole system it cost $1800 just to the welder. Probably more now.