The V 20 hits 50mph tops, but any faster ?

[spareparts]

I'd raise teh engine to the top hole and try the 21 Mirage, if you get the engine too high, you will know it, then you won't have to wonder how it will run rasied anotehr hole, its allways easier to drop the engine down a hole than raise it. Liek I said, my friends 20 grady spins a 19, its a heavier boat than a V, plus he has a big T-top with full cnavas. That 225 Yamaha spins teh 19 with no problem. I don't remeber the different gear ratios on teh Yamaha verses your 250 Merc (1.75 i think), but I'd guess you should be able to spin a 21.