I don't. Where do you get those three pounds from? The larger engines I am discussing are, at most, a half-pound heavier than an OS 91 Surpass (which I have, but in another model) and, I presume, a Saito 1.00.

But you're right, the 15"-16" props those engines require would simply not work with the stock LG. Which is what I suspected. Your information confirmed it; thanks.

Regarding the firewall… did you reinforce yours by adding a second thickness of real plywood, as detailed way back in this thread? I have no doubt that some additional fuel proofing will be needed, and perhaps some tri-stock here and there. But slapping on another firewall over the existing one is pretty… severe. Necessary, you think? Or not?

Off to check out the Saito 1.00...
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