1948 170 Engine Conversion

[N4134V]

All:

I recently purchased a 1948 Cessna 170. I would like to convert the aircraft to 180hp or greater with a constant speed prop. I realize there are limited (if any) STC options out there. I really like the rag wing, and I'm willing to go the route of field approval, or just make the airplane experimental if need be. I have no experience with such an endeavor and I'm looking to the group's knowledge to point me in the right direction.

Thanks in advance to anyone with advice!

Anthony S. Pentz II
330.904.5066
anthony.pentz@foxtrotaviation.com

[GAHorn]

I’m not the best person to comment on this, but the first thing you should consider is cost. Do you really think it will be worth keeping your current airframe which can likely only be converted to higher horsepower at increased cost above/beyond what other models 170 cost? To convert A or B models typically cost $50,000 if you cannot do the work yourself, and $30,000 even if you can do it on your own. To convert a ragwing (for which there is presently no STC) would cost even more. Do you seriously think you want to spend that kind of money to end up with an airplane which will be severely weight-limited ? (Because engine conversions always weigh more but do not add useful load.)

It would be far-better in the view of most people to either purchase an already-converted airplane.... or to purchase a different model aircraft.

[Richgj3]

In addition “making it experimental” is not easy or in some cases possible. Experimental has three basic categories. Experimental Amateur Built, Experimental Exhibition and Experimental Flight Test. You can’t be Amateur Built because you won’t met the 51% rule. If you go Exhibition then you must provide your local FSDO with a list of places you will be taking the airplane for exhibition. If you go Flight Test then there is a prescribed period at the end of which you need to use that data for an STC or a field approval.

Years ago I bought a 1958 172 with a tailwheel conversion. It looked nice and flew well but had Stone Age radios and the 145 hp motor. I thought about that conversion and avionics for a bit until I realized I could sell it and buy a 250 Comanche with IFR radios for less than half of what I would have to put into the 172.

My opinion. Your mileage may vary

[alanbaker]

I think a lightweight early 170 with a 180HP engine would be sweet! If you have the means you should try it!

[n2582d]

Tom Anderson's Continental IO-360 conversion, SA00728SE, is available for the '48 C-170 . I'd recommend you talk to Jim (aka Metal Master) before beginning such a project.

Click to Enlarge