You won't notice much difference between the 120 and 140. You can probably
put the v6 in it but it will be more expensive than the boat is worth unless
you do a lot of it yourself and find a donor boat. Three tubes is a big
load. Unless they are one person tubes. I sometimes pull two big tubes
with my 5.7 and it takes a lot to get going with them. What you want is a
bigger boat.

"crystalguy" wrote in message
oups.com...
I own a 1981 17.5' open bow Stingray.
This boat came with Chevy 2.5 120 HP
The eingine and boat were abused over the years by previous owners.
I have redone the exterior but the engine lacks power.
I would like to do an Engine swap.
Can anyone tell me the most HP I can get without too much hastle.
I would like to try a 3.7-- is this a possibility?
or would a 3.7 be too much weight.
Boat is rated for 1000 pounds Engine and gasoline.
What about a 3.0 140 HP
WE want to be able to pull 3 tubes and still have 4 people in the boat
or would I be better off looking for a bigger boat?
I have only had this boat 1 season and have never been able to get it
over 30 mph which is with just me in the boat, usually 25 is tops with
other people in the boat.
The spec on this engine says 3900-4300 WOT but even down pitching the
prop only got me too 3100 rpm.