switzer ss240 questuions
 

i have a switzer ss240 with a 454 and bravo 1....bought it last year,, i was told it had a rebuild about 200 hrs ago and has a mild cam. why am i only getting around 52 m.ph. out of it when ive seen these boats in the range of 60 to 65,,and higher,,, i have 23 pitch stainless prop as well.. im relatively new to boating mechanics.. im at about 4700 rpm too.. what changes can i make to get this speed up alot??
:evilb:

any help is greatly appreciated

Is that 52 on the speedo or GPS

It's on gps,, speedo not working

Well, you're actually turning about the right RPM's - maybe a few hundred high even. That hull doesn't have a ton of deadrise, so it's generally pretty quick. If you want my 2 cents, I'd say that motor isn't putting out nearly what somebody thinks it should be.

fixx
 

take it to a scale and have it weighed...i bet its foam is saturated with water?? i remember when they were building them in mcKenery countyin il..with a 454 365 mag they would do around 70 mph and that was with a mirage + propeller..if you have a 330 then 60 was a good number..

I have a 21 pitch prop as well,,that u havnt tried yet...do u think this will give me a little bit more speed?? Or go up to maybe a 25?

With a boat, you run whatever pitch prop allows you to run maximum safe RPM's at wide open throttle. So a prop is like a gear. With a given power output, less pitch will allow your engine to rev up more. More pitch will drop RPM's.

Since you're already turning at or just over maximum RPM's, dropping to a 21" pitch will just over - rev the engine and a 25" pitch will drop RPM's, but possibly gain speed. I'd try the 25" just to see what it does, but leave the 21" in the box. (That'll also leave the rods in the block.)

And as Mr. Fixall said, you may have a water retention issue with your hull. Lots of extra weight will have the same effect as being down on power.

This may be a silly question, but how much boating experience do you have? Are you trimming the boat out to get maximum speed / RPM's? I've run into several people who didn't know anything about that.

This may be a silly question, but how much boating experience do you have? Are you trimming the boat out to get maximum speed / RPM's? I've run into several people who didn't know anything about that.[/QUOTE]

I was thinking the same thing.

Yes I trim all the way up till it almost comes out of the water at top speed.. I agree ill try the 25 pitch and see what it does.. do u thing maybe I have a fuel problem?? U always smell gas and there are no leaks.. but seems to run good.. gets up ,,but then just plataeus or flatlines