I have tested the 3241 mufflers with the larger engines. They start gaining power above 16500 rpm, where the 3243 slowly cuts off. Rpm range of the .26 engine thus becomes 12,000 to 19,000, which is quite flexible to say the least.
I am afraid these engines will soon be a thing of the past, until order numbers are kept up. No company can market a product and operate at a loss.