Im looking at getting an aircraft that says it can take a .61 to .80 sized engine. I have access to a .91 sized engine, would this be a good way to make my plane end up in pieces, or would over powering it be OK? Specificly im looking at the Top Flite Corsair
http://www2.towerhobbies.com/cgi-bin...?&I=LXHU80&P=7

The 91 will be a good choice for this plane especially if you decide to glass it, add retracts, etc. Be advised that a Corsair (in ANY scale ) is one of the more difficult birds to successfully fly.

Ditto Campy, since many .90's are sort of bored out .60's that weigh about the same or slightly more, like the OS's and Super Tigres. It's always nice to have reserve power when you need it, as long as there isn't much weight penalty. Also teaches throttle management.

Happy Landings.

It will be an excellent choice.

Enjoy,

Jim

Actually I think today's 60's are underbored 90's. They certainly weigh like it. Looking at K&B, Jett, Webra and others we see that a 60 made to be a 60 is considerably lighter.

A 60 size plane in the 65" w/span range are able to just fly with a 60 sized 2C engine and would be fun with a 90 sized 2C, if you get a 108 2C it will be totally fun! Even with the 108 2C it is not totally overpowered yet. The wing loading would have gone up a bit but still manageable. What is most important is vibration (too much vibration will cause structural failure), fuselage integrity (wings ripping off, engine coming off the firewall) and over speeding (flutter, wings snapping off, stabs coming off).

The topflite Corsair is right at home with any "60" sized engine. Not long ago (or at least I like to think 'not long') the engine I used in the Corsair was a ST-75. Perfect balance of power, prop and reliability.

Using one of the modern .90 size engines is an excellent idea. In fact, the ability to turn a larger 13" - 15" dia prop is a serious bonus.

The ST90, OS91, Jett 1.00 and a handful of others "60 size" engines are excellent choices - all very much right at home turning a bit prop.

Some of the slightly larger "90" block engines are good choices too. That OS 1.08 is a wonderful choice in this application. A ST2300 might work well too (sometimes you need the nose weight, so why not make it useful nose weight).

In general, you are not "over powering" the plane with a slightly larger displacement engine. The key here is good flight performance, which in this case is enhanced with the larger prop. Larger prop, throttle back in flight..... nice pleaseing sound and good scale performance.

Image I had available here is a Top Flite Corsair with a jett BSE-120L and turbo-jett installed.

Bob