BH>I've got a 19' 3500 pound steel cabin cruiser of sorts, with a 4 Cyl. 120 
HP
BH>Volvo engine (a rebuilt 1970's model).  The boat can get up onto plane 
ust
BH>barely but any kind of wind resistance or other factors including a single
BH>pound of added weight can cause it to lose the plane and the speed
BH>absolutely sucks.
BH>I'm wondering what I can do to maximize the amount of power this engine 
puts
BH>out, as well as speed.  Should a propeller change be investigated?  If so,
BH>which way would be correct to go pitch-wise?  More acceleration or more
BH>speed?
Brad, first, I don't think you are going to convert this boat into a
speed demon without repowering.  120 horsepower is pretty light in
today's day and age.  But you can maximize what you have, and to help
you, I need more information. What is cruising RPM, and what is full
throttle rpm?  Also, check the Volvo book to find out at what rpm full
horsepower is developed.  I think you understand that changing the pitch
of the prop will either give you more accelleration (lower pitch) or
more speed (higher pitch) but do not overlook that higher pitch will
just bog down an engine on an underpowered boat/engine rig.
BH>Is there anything I can do to the hull itself to increase speed?
Cut off everything above the waterline to reduce weight. ;-)  If you can
find the information on a rig this old, find out if it was offered in a
higher powered version and what the performance/handling characteristics
were.  There may not be much hope here...
BH>Can I turbocharge or otherwise modify an engine that old to squeeze
more BH>power out of it without hurting it?
Dunno.  Volvos are pretty sturdy beasts.  Contact Volvo and see if there
is a turbo option for this engine.  Watch the cost though!  Sooner or
later it will be cheaper to go get a new one...  New ones come with
warrantees, too... a handy feature which I don't think you could get if
you were turbo-ing a 1970's engine.  How many owners has this engine
had, and do you know them well?  What kind of care has it had?
BH>Any help would be GREATLY appreciated.
I'm not sure this is help, but I'll try!
 * OLX 2.1 TD * ...Lead me not to temptation for I can find it on my own.
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