The Macs black pipe muffler for the 46FX--TT Pro 46 works on the LA46 if you drill out the holes in the case a little bit. Makes a lot more power.

I wonder if the Macs muffler for the OS 40FX and the TT Pro 40 would also fit on the 40LA?

I just had to widen the hole spacing a little bit for the Macs pipe from the 46FX to fit on the 46LA. I posted some numbers on here a few months ago. Maybe do a search for 46LA Power Modifications Can't remember what I titled the thread.

It made a big difference.

Put a header on it and a cannister. Or a header and a full tuned pipe.

Take the head shims out and put some 25% nitro through it. Or put some 30% heli fuel in it--the kind the Saito guys use. It's got oil and nitro. Should give that engine a bit more snap. Just keep in mind that the tighter you wind it up--the more oil you need in that plain bearing crankcase. I don't know if a crank will seize under very high RPM or not, but if it was me, I'd be bumping the oil up to 25% or more if you really start making any kind of serious power with it.