Which duoprop

[bluecollerboater]

I have a 1995 Carver 250 Express. Looks like a Searay. 28 O.A.L. Weighs 6100 pounds with fuel and water. I figure 7000-7500 pounds with all my stuff. It has a 260 H.P. Carbed 350 and a Sp-c1 outdrive it is a 1.95/1. It had a B-5 when I first bought it. Way over propped. I could only get 3900rpm. I put a set of B-3's on it and can only get 4200 rpm. My W.O.T should be 4200-4600 rpm. Should I jump down to a B-1 set or go with B-2's. I am looking to hear from anyone with a similar set up. A heavy single engine boat with a 350 and duoprop. Anyone try either B-1's or B-2's on a similar sized boat? Thanks in advance for any insight.

 

[Scott Danforth]

with B3's you should be able to spin up over 4600 RPM. the Carver 250 weighs about the same as my buddies old 25' Carver Montego twin cabin (I think the same hull mold) that had a VP 271C and 290 drive nearly same as yours) and would have no problem hitting WOT with 8 people and two dogs on board and 200# of ice and beer

I suggest you start looking at the motor and the stickies at the top that deal with low WOT.

 

[bluecollerboater]

The engine is in good condition. 10 hours on remanned long block. New spark plugs, wires. Fuel filter and timing is good at initial and full advance.what else should I be checking?

 

[Scott Danforth]

read the stickies on low WOT
did you get a generic reman or did you have your motor remanufactured?
did you go thru the carburetor?

 

[bluecollerboater]

It was a Jasper reman. The carb was rebuilt.

 

[Scott Danforth]

a generic jasper reman or a volvo specific jasper reman?

 

[bluecollerboater]

It was a marine remanned 350 long block. I do not think it was Volvo specific.

 

[Scott Danforth]

The reason I ask, Volvo runs a bit more lift and duration on their cams than mercruiser does. its not a lot, however comes out to about 10hp or so on the 570 and 572 vs a stock 260hp 5.7 (about 30 more with the AQ311 / 571 motors)

may be worth while to dig into the specs for what was in their originally

back to your motor. Edelbrock or Holley carb? im going to assume an edelbrock. if so, do you know what calibration kit is installed?

have you had your boat weighed or are you going off of dry weight?

 

[bluecollerboater]

Weber carb. I am going off Carvers specs of 6100 with fuel and water plus a 1000 pounds of my stuff.

 

[Scott Danforth]

I suggest weighing your boat