RE: EP/GP Modification to 41" jet speed boat
Time for a level set here, the suggestions appear to be wandering all over the place. While the boat is larger than the typical .21 size, since it's an ABS electric right now, it may not be strong enough for a .45. You are definitely going to have to put in some reinforcement to hold the engine, and probably on the transom. Trying to put in too much power is going to lead to durability problems, and most likely handling problems too. While a .21 won't turn it into a rocket, it may be a better choice than something larger. Given a choice between a .21 marine, or a .45 aero converted to marine, I'd go marine. The .21 also give you the option of the pull start, which you said you want. Take a look at the OS .21 RG-MX.