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nieszrj
11-12-2001, 02:04 PM
I have a newly rebuilt (completely stock) 1978 Mercruiser 260 and a fresh 1978 Type 1 Mercruiser outdrive.
I have about 1500.oo I would like to spend to squeeze some xtra top end out of her. The boat is a 1978 Sea Ray 25 foot. I know, it's not much of a "hot boat", but it's what I got.
The current top speed is about 32.
I have been told to focus on:
Intake
Ignition
Carb
Exhaust
Heads
Cam
but I don't think I could afford all of this!
Any of your recommendations would be greatly appreciated.
Thanks a lot,
Russ

Tinkerboater
11-12-2001, 06:03 PM
I wouldn't spend the money on this boat. A 25 ft. boat with only a 260 hp. small block will not make you happy even if you get to 350 hp. that is the max that drive can handle and still hold togeather. The only thing you will gain is maybe 5-7 mph but the boat will come on plane quicker and pull skiers better.. I suggest putting the money towards a different boat - possibly a hull designed for at least 60 mph stock.

racingrascal
11-13-2001, 08:28 AM
Tinkerboater maybe he isn't trying to go really fast, maybe he just wants to super size what he allready has. If so look into making it breath better either through the exhuast or the intake. There are a lot of small things you can do with out getting into the motor. Ratio rockers,intake, different carb.,headers,ingnition upgrades. I am sure there is a lot more then what I suggested but I would look into some of those.
Andy

spectras only
11-13-2001, 03:03 PM
the problem with a 1978 25 foot searay weekender is ,it won't perform without changing to a BB .The maximum size for a 350 SB is the 22 foot searay weekender with any performance.These boats were built for rough water .I would look into a 19 or 22 Pachanga models that came with 350 Magnums.Or a 27 Pachanga with a BB if size matters http://free.***boat.net/ubb/biggrin.gif.The 25 is a nice cruiser ,I think a searay dealer would be able to do a swap with some change.
[This message has been edited by spectras only (edited November 13, 2001).]
[This message has been edited by spectras only (edited November 13, 2001).]

Tinkerboater
11-15-2001, 07:24 PM
I wouldn't consider a 5-7mph increase in speed from 32mph going really fast. small changes to a small block will only cause other problems or noise ( not music like a properly set up engine.) That hull with an alpha drive will never make him happy. I've been down that road.