470N cylinders on E225 case

[noslonlo]

We're considering the STC from Aviation Research Systems in Sandy, OR that allows us to put 470N cylinders on the E225 case in our 1956 G35 Bonanza. Any thoughts or experiences with this company?

Thanks.

 

[Geronimo4497]

I have not personally heard of this company before. Just from the fact the 225 parts are becoming increasingly difficult to come by, I would say that this would be a good conversion to consider. How much time on the engine right now? The 225 is a good engine, IMO.

 

[noslonlo]

The E225 engine time is just over 1600 hours. I hadn't considered the lack of available parts for the E225, but that's a good point. I like this STC because it increases the horsepower to 260 and seems much less involved than an IO520 conversion from DeShannon. (The DeShannon is a 300hp) It would be great to be able to talk with someone who actually has this STC on their airplane.

 

[capt_zman]

I used to own a 54 E-35 and researched this back in the day. It seemed that the deshannon conversion was way too cost prohibitive. Don't know much about the cylinder STC, sounds like it could possibly be a decent deal.

The 225 is a great engine. The IO-520 (in my experiences with barons) is not-so-great. Had to replace both of them on my 58 due to case cracking, which they are notorious for. 520's are pretty expensive, as each factory reman, after everything was said and done, cost about 35k apiece. I'm sure you could save a little off of that price, but considering the cost of the engine, prop, STC, cowl, labor, it would sure seem possible/likely to spend more than 60k to do this conversion.

And the real question is, do you see that much of a difference in performance. If I remember correctly, with the e225, I use to true at 135 kts. With a 520, I would guess that number would increase to 160 or so. That's alot of greenbacks for 25 kts.