RE: info on supertigre .61X K fire engine
Is that the one with the square head?
I asked the same question in the "Club Supertigre" thread in the Glow Engines forum...
Another answer I got (elsewhere ) was that the X .60-.61 was of the "Pattern" era when everybody was trying to spin an 11 X 7 as fast as they could, and it's ported and timed to rev.
I'm far from an expert on them, but from the info I have gleaned, they don't need/like a lot of nitro either...and prop it to rev.
Mac's would have a 10cc size pipe...just need a header.
Do you have a cast on to the cyl. round exh. stack, or a flange for a bolt on pipe adapter?