What modern engine would be equal to OS25FP?

Would a modern 15 engine like OS15 LA or
Magnum 15 be the equal of the OS25FP?
Looking at Pat Johnsons Stunt Trainer but dont have a 25FP moto Alternatively is there a suitable profile trainer
to suit modern 35 motor?

Any ideas.?

Vincent

Vincent Corwell

>Would a modern 15 engine like OS15 LA or
>Magnum 15 be the equal of the OS25FP?
>Looking at Pat Johnsons Stunt Trainer but dont have a 25FP
>moto Alternatively is there a suitable profile trainer
>to suit modern 35 motor?
>
>
>Any ideas.?
>
>Vincent

The Thunder Tiger 25 is a direct clone of the 25 FP except for the venturi. These are a better quality, less expensive engine, and adding a venturi and needle is easy to do.

Don't overlook the ASP or the Leo .25's. Both are proving to be excellent .25 sized engines.
Joe

AS MR. BIG JOE has stated. Or OS 25 LA......Did I miss something?

I thought that an LA had no power advantage over the FP series. So, an OS 15FP is equivalent to an OS 15LA. Same for the 25.

I am basing this on my recollection of OS's own numbers, and could be mistaken. So please correct if I am off base here.

The OS .25LA probably has better mid-range torque than the FP, if it doesn't have the boost port. I think later ones do not. I had a Pat Johnston "Stunt Trainer" given to me by Jim Johnson. Jim flew it with a .25FP, but I flew it with a Magnum XL .25, tongue muffler and 9-4 Taipan prop. Any .25, and many .19's would fly it well. It builds light, and is a nice size for sport stunt.

The OS .25LA's are nice runners, esp. if you lose the plastic backplate and rear NVA (TT .25 backplate, socket head screws and I'd hold out for a Randy Aero NVA). With the highly recommended stock muffler, they are barely audible from the judges position on the opposite (and upwind) side of the circle. Steve