Hi Guy's,

I need a complete exhaust for a PA18A-150, I usually buy Knisley from RAM Aircraft but they've screwed me on several warranties recently so they're on my sh*t list.

Any suggestions for a decent, cost effective (cheap) PMA'd system? Will be shipped to New Zealand..

Cheers!

There's a guy named Sonny Poarch who advertises on Barnstormers. He sells several types of exhaust systems. I believe some of his systems are PMA and others are "owner manufactured" under the appropriate FAR.

If an exhaust meeting the FAA "owner manufactured" rule is legal in NZ, then you would have several other options.

There have been many discussions of Supercub exhaust options on www.supercub.org The "search" function works fairly well there. Honestly, some of the soundest technical advice anywhere on the internet there, and not just Supercubs. Quite a bit of dialogue from all over the world. And it's interesting that so many folks hang out at BOTH backcountrypilot.org and at supercub.org

Thanks. cubscout

Use one of these exhausts on one cub and you'll wonder why anyone would ever bother with any other;
http://www.propilotsinc.com/exhaust.html

Take care, Rob

For a certified cub-propilots. for a experimental-vetterman.

Rob wrote:Use one of these exhausts on one cub and you'll wonder why anyone would ever bother with any other; http://www.propilotsinc.com/exhaust.html Take care, Rob

I know a couple guys with these Sutton exhausts and they look like a better idea than stock. No extensive tubing & muffler cantilevered off the back of the engine--just down, into the muffler, and out. I can't speak for performance gains or lack thereof compared to stsock or other aftermarket designs.

Thanks for the replies, the propilots looks good, much better than piper's effort but a little spendy. Customer might want to go that way though

Hey EZ, no the owner manufactured thing is not so easy here and always cost more in the end. Welding shops have fairly limited capability and really only do patch up jobs. I have the gear to do it but not the time. You guy's are spoiled for choice over there!

Cheers

I have the Sutton exhaust and like how simple it is. Clears up lots of space behind the engine for easier MX. Performance wise, I have nothing to compare it to, but you can be sure it's no less than a stock system. One thing to be careful of, though, is the clearance behind the starter and generator. If you have a lightweight starter and an alternator, it should be fine.

Another benefit to the Sutton STC is it allows (not requires) you to mount a lightweight oil cooler to the rear #4 baffle...gets that heavy brass cooler off the nose along with the associated plumbing.

EZFlap wrote:There's a guy named Sonny Poarch who advertises on Barnstormers. He sells several types of exhaust systems. I believe some of his systems are PMA and others are "owner manufactured" under the appropriate FAR. If an exhaust meeting the FAA "owner manufactured" rule is legal in NZ, then you would have several other options.

That "owner manufactured" business sounds great, but who here has actually done anything with it? You could theoetically hang any old thing on your airplane & claim "owner manufacture" -- borer prop, bushwheels, landing gear, etc. As a way to get around an STC or field approval, I don't think it'd fly with my IA or my FAA inspector, except possibly in the case of (small) stock parts which are unavailable for purchase anywhere-- which I believe is the intent of the rule.

We would call it MITCOM in Aus, 'Manufacture in the Course of Maintenance' I assume EZ means the same thing?

An example is you remove a corroded skin, determine it's 2024T3 .032" and make an identical skin from the same material. The part cannot be sold for use on another aircraft

The important thing is you're making identical parts from identical materials with traceability. I guess you could make an exhaust but difficult to copy the original without extensive tooling and the labour may well end up costing more than the aircraft!

It's not intended for modifications from the TCDS. We do it quite often, for example Vulcanair can't supply replacement main spar angles for the P68 series (even though they're still in production, go figure..) So we buy in the extrusion and machine them inhouse. Perfectly legal in Aus and NZ. But always have the original material analyzed first!

We call it BI equipment in my circle: "between inspections".