I'm currently running a 496 HO mag with a bravo 1 on my checkmate 270BR.. Is there a formula for measuring "drive height" and what could be the pros and cons of shortening the lower other than possibly less drag/more top speed? Thx

Its not that easy. Find somebody with your hull and get a baseline. Too high and you wont get on plane or if you do get on plane it might not carry the bow.

Its just testing... 1 inch at a time.

Thx

these days most boats are built with drive height being the last consideration. the lower they get the motor in the hull, the better seats or sun pads fit above them. and if the same power only gets you 60 instead of 66, well too bad. if you can find a shortie drive for reasonable money, you can try it and always resell it for no loss if it doesn't improve performance. drop the drive down and get behind the boat. does the cav plate line up with the keel? or is it a couple inches below it. (this is when drive and cav plate are parallel to keel-not all the way down) this'll get you an idea if drive is down too deep or in the ballpark where it belongs.

Thx 4 another great reply... Now I'm just a little curious of what kind of money for a shorty would be a good buy? Lol
And other than mph, does a shorty offer better handling?

I bought a -2" Imco then added a 1" spacer .
Cons are Imco -2" lower has only one small water inlet on the front of the bullet,
it is easy to plug with weeds .

j stud - What kind of boat do you have?


Maybe you can get some better input if you elaborate a little....