Powerflow exhaust for M20J

[Magnum]

I am thinking about getting the powerflow exhaust for my Mooney. As I have the electrical cowl flaps I'd have to install the first generation. Does someone have real world experience with this exhaust? Is it worth the money?

Magnus

[mooniac58]

I second this - I would like information on experience with the exhaust.  I have manual cowl flaps though.

[N57039]

I have the PowerFlow on my 201 and am happy with it. Unfortunately I didn't do any real "before" tests. Therefore I can't give any performance improvement claims. It's a solid, good looking system. I'd be glad to answer any specific questions anyone has about it.

[Magnum]

Quote: N57039

I have the PowerFlow on my 201 and am happy with it. Unfortunately I didn't do any real "before" tests. Therefore I can't give any performance improvement claims. It's a solid, good looking system. I'd be glad to answer any specific questions anyone has about it.

[GeorgePerry]

A local mooney owner and A&P at KPVG had one of the first Powerflow systems on his E...I asked what he thought about it and he said "don't waist your money".  He went on to say that he did do detailed before and after testing and in the end, returned his plane to its' stock configuration. 

[N57039]

I guess I have an "early" 201 system. PF offered a retrofit preheater to improve cabin heating. I bought it, and it's installed. However, it hasn't been cold since the installation, so I can't rate the improvement. Previously in climb the heater was inadequate. Once level with cowl flaps closed the heater was fine. I hope the preheater solves the climb heat problem. As a slight side benefit the preheater improved the position of the heater hoses. Had rubbing problems before.

I think the PF is a little louder than the stock system. It sounds good to me. I don't regret spending the money for the system. The exhaust that came with the plane was shot and had some non-documented, non-Mooney parts on it. I had to do something. For me the PF was very timely.

[Magnum]

Thanks for the information. My stock exhaust needs some maintenance, too, and that's why I am considering the PowerFlow.

[TurboExec]

I've read a few articles about the performance gains on a Mooney with PF exhaust.  It is along the lines of 4-5knots in cruise and 100-200fpm in climb.

What is the reason you want to get it...besides the potential gains.  Is your exhaust in need of replacement?

[mooniac58]

Quote: JimR

We recently picked up 4 knots at WOT, best power, 2500 RPM at 8500 feet in our '65 C model with the latest generation PF exhaust.  Fuel flow went up as well, though, perhaps a little less than a gallon per hour.  In theory, you can throttle back and experence gains in efficiency, but in practice it is very hard to pull the throttle back from the stop!  I'll probably go with a new exhaust from www.aircraftexhaust.com for less than half the price next time. 

 Do the exhausts from AircraftExhaust.com give you the same performance gains as the PF?

[FlyDave]

Not sure if anyone is still interested but I just found an article on the Mooney Owners website on the Powerflow Exhaust:

http://www.mooneyowners.com/pdf/Nov06/nov06web.pdf

[KSMooniac]

I can't believe they optimized it for 11,500 feet...engine power drops off quite a bit up that high so I don't fly there unless there are very favorable winds or I need to get over some turbulence.  I don't think I'm alone in that sentiment, either, for non-turbo Mooney pilots.  Too bad they didn't pick 7 or 8k feet.

[TurboExec]

Yeah 7 or 8k where just about everyone cruises would have been a better idea.  Of course with you are trying to top those building cumulus you'll be glad to have those extra few horses.

[airkraft]

I've read that the PowerFlow does indeed increase performance on the carburated Mooney's.  Not heard anything positive for injected models.  I can attest to increased performance after PowerFlow installation on our 172.

We purchased a new exhaust from aircraft exhaust.com last year when we overhauled our IO-360A1A.  In hindsight it would have been less expensive to have the original overhauled.  (As I understand it, an overhauled exhaust is essentially new anyway).  We had to modify the old heat shroud as Aircraft Exhaust did not yet have PMA authority to provide new one. Something else needed modification, but I can't recall what it was.

Knisely (sp.?) builds the exhausts in California for Aircraft Exhaust.com. They are very high quality units. No performance increases were expected or observed. 

 

[Piloto]

Going by aerodynamics mathematics a gain of 7kts at 11,500ft on a Mooney 201 would require a power increase of 15%. This would add 75fpm on the climb rate. This would mean that the standard exhaust is very inneficient. Another more accurate way of comparing exhaust is by measuring the differential pressure drops between the two by applying compressed air. This would provide a more accurate quantitative figure than flight testing. In none of the test mentioned there is no mention of an engine torque sensor to measure engine power. TAS alone is not an accurate way for measuring performance change. Aircraft weight and density altitude can affect substantially TAS.

José