I have a couple of new Double Starr 40 engines on which I have increased the venturi size to what it should be to give proper power. (The original Double Starr venturi is too small) These are 40 size copies of a Fox 35 (same outside dimensions) with a true ABC piston/cylinder and include a Double Starr copy of an Adamisin muffler (1.3 ounces). The muffler, alone, is a $30 value. $100 complete for each. Add $9.50 for a second, larger, aluminum venturi and you will have options to work with to get the best run for you. US dollars. $3.50 shipping priority mail. Foreign shipping at cost.
Leonard Neumann