You did not mention model. Year is irrelevant. If it's an old 2-stroke, such as an M25C3, just remove the intake gasket restrictor and reset timing. If it's a 4-stroke, you need a different ECU. Luis has a complete procedure elswhere on this board.
You did not mention model. Year is irrelevant. If it's an old 2-stroke, such as an M25C3, just remove the intake gasket restrictor and reset timing. If it's a 4-stroke, you need a different ECU. Luis has a complete procedure elswhere on this board.
To start with must swap the M25 carb/intake gasket for the M30 gasket which has a larger internal dimeter to allow more air intake and advance the timing from 20 deg to 25 deg. This mod should have its own stickie as it's asked a lot here. Check Tohatsu 25 to 30 HP conversion under Find Threads or Search Forums....