Stinson L-5 has a nice system!!

http://www.ebay.com/itm/L-5-Stinson-exh ... 27e2f03b9e

MauleMechanic wrote:Stinson L-5 has a nice system!!

http://www.ebay.com/itm/L-5-Stinson-exh ... 27e2f03b9e

Doubt that there are enough fence sitters but currently there are only 6 deposits and nothing is going to happen unless there are 29 more:
"Number of deposits required before STC program launches: 29. Deadline for sign-up: April 30, 2014."

I'd jump off the fence for $3000.00 but they would need 100+ committed folks in order to move on that price point. Guess it isn't going to happen this time around.

I have mine ready to go in so I will be 7 or 8. I spoke with Powerflow and it sounded like they were going to extend. I'm hoping Maule factory will contribute to the cost. What I was told is that if you pre-order then you will be eligible for the discount. I was also told that your credit card would not be charged until the STC process began.

If Powerflowsystems is monitoring this, it might help to confirm that. I just don't see a downside to this quite honestly but each owner has to make his own decision. I can only speak for my own perspective.

Hot dog! 27 more and we are good to go!!

Anyone know if PowerFlow is still working on certification for the Maule Exhaust?

Don't think they got enough takers at the price they were asking.

Had the opportunity to see a new Power Flow exhaust installation at Maule Flight last week while in Moultrie.

Apparently the owner had gotten a field approval, a few years back and hadn't had it installed.

Kit Wilkes and the crew installed the Power Flow following a major overhaul due to an engine making metal problem on the Aircraft.

Nice looking installation. Wish I had gotten the N-number to try and secure a copy of the field approval.

Wonder if more field approvals are possible for the Power Flow installation?

I saw the Power Flow system that they proposed for a 180 hp several Maule Homecomings ago but I wasn't overly impressed. It took up a lot of room in the cowling due to many u-joints welded together. It was heavier than standard exhaust with modest proclaimed gains in fuel efficiency and power, but no actual data. Not worth the $4K they wanted up front in my opinion. I've seen better approaches to the weld-cracking problem using spring loaded ball joints but I don't think any of them have been done for the 4 cylinder engines.

I ended up taking the power flow system off of my 172 that is a training plane. IT fly's 600-700 hrs a year and I was having to replace or have it repaired once a year due to cracking. I liked the system other than that. If it was a personal Plane that was not getting beat to death all the time I have to wonder if the out come would have been different....

It sounds like Atlee Dodge or Tim's Air has the best alternatives going, if the "loose" fitting approach still results in cracks etc to the stock mufflers.

The problems that I've had with my Maule exhaust system are mostly in the welds where the pipes come into the muffler. I think it's due to a combination of more vibration with the 4 cylinder engines, movement of the slip joints, relatively thin pipe walls and welding technique.

I think TimB has done alternative systems that are better designed but I don't know if he's done any for the 4-cylinder engines.