needing to get a engine for a 580 cap that i traded for, the guy i traded had a os 46 fx in it but was in the deal he could keep it what do you guys recomend putting back in it the same or something else was wondering about the .55 ax

It would help to know who manufacturers your plane, and which model it is?

probably would opjose!! its a matt chapman .46 great planes.........sorry about that!

You would have no problems with the AX.

If anything that will really make the plane fly well.

so it should mount the same and i will still be able to use the pitts muffler?

I'm not sure about the dimensions of the holes.

But I'll bet you can find this out at Tower's site, by looking at the replacement parts for both engines.

Assuming he had it assembled and the holes in the cowel already cut you are pretty much stuck with using the same motor he had in it unless you want to patch the holes or buy a new cowl.
I have an OS 70 4 stroke in my Cap 580.

i was wondering that missleman but i read where the two engines are about the same size wise that is the .46 and .55

I believe the AX .55 is sold as a "drop in" replacement for the .46 FX/AX with the same mounting hole spacing and dimensions.

I just check Tower's site and the same Pitts Bisson Muffler is offered for both the AX .55 and the .46 FX.

Except for the slightly longer/higher "head" of the AX, it should drop right in and he can use the same muffler.

At worst he may have to cut out a bit of additional cowl material, but that should be about it unless I'm missing something.

A fellow club member has one that flies great on a rather worn OS .50 SX. I think the OS .55 AX would turn it into a real barn burner.

Hogflyer