Do engine STCs help or hurt resale value?

moparrob66

Pre-takeoff checklist
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Moparrob
I just took delivery of a 172B with a high time O-300. It seems fine for now, but I'm getting bids for overhauls and its all quite shocking. Ive had estimates as high as $44k and as low as $33k not including removal and installation. I think I could get a Franklin 220 swapped in for less than $36k with some sweat equity and sell the running O-300 and prop to offset that cost by maybe $10k?

The franklin has some drawbacks like parts availability and no tolerance for mogas, but the performance gains are significant if not monumental.

What is the consensus on resale value of an STC'd engine change vs. low time, stock engine?
 
crazy right? Powerplant pricing is the death knell of this recreational space. Kicked me right off airport property last year, no cap as my Gen Alpha kid likes to say...

good luck.
 
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I don’t know about 172s, but the higher HP replacements in the 182s are desirable. If anything I don’t think they hurt resale. Greater fuel burn might be a negative to some. If it’s a timed out STC, one can always go back to the factory offering, again not hurting resale.
 
I think a C172 with the Air Plains or Penn Yan O-360 conversion increases value. I'm not so sure about the Franklin conversion. It sounds great, but there aren't very many of them and as you mentioned parts look concerning. There's a C172B on TAP with a 400 SMOH O-300-D for $45K. I would be tempted to buy that and swap engines...
 
Most people are paying to replace their franklins with something else.
 
Maybe the manufacturers assume that pilots are all gazzilionaires? Most people I talk planes with are shocked that my 172 costs less than a new, base model pickup. I have ordinary income with ordinary obligations but I eschew car payments so I can afford...airplane payments.
 
Before Cessna started putting the 180 hp in there 172s the airplains mod always sold for a premium.
 
You can’t go wrong with the del air conversion, upgrade to the cs prop and you have a wonderful plane
 
The STC only helps if it's a well know, well trusted source. A Franklin is cheaper for a reason. I wouldn't buy a plane with one.

A 182 with a monster Continental? Hell yeah...
 
 
^^^good read....thanks! Aside from perceived parts availability, why would a 180 horse O-360 be better than a 220 Franklin? I ask because I dont know, not because I'm stubborn. The 220 Franklin is 350 cubic inches, 10 fewer than the O-360, so the fuel burn could be a smidge less. Or maybe not since the Franklin is a 6 cylinder vs the 4 cylinder Lycoming.

If going from 145 horsepower (on a good day, new engine, etc) to 180 horsepower is good, wouldnt ANOTHER 40 horses be stupendous? Does anyone ever say "gosh, I wish this darn thing had LESS power!"?

I dont think the Lycoming is more popular because its a better design. In fact, i think the franklin is designed better, but perhaps the company has other struggles that Lycoming did not.

As far as "Just buy a 182" that may happen someday. But this plane is the one I can afford now, and the engine will need overhaul or replacement with SOMETHING before I can possibly upgrade.
 
M2C. Overhaul of a normal engine is expensive enough. Parts availability and A&Ps who know how to work on your engine is a major consideration for what you can afford to fly, as well as not have the plane sit more than it flies for lack of mechanical support.

The 180 HP conversion is still out there, A&P’s can get parts as well as know how to correctly work on it.

It would be great to have a supported 220 HP engine vs 180 let alone 150. But I want to fly and not have it sit, not worry about lack of support on a XC, exceed what I can afford in unexpected maintenance, etc.
 
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