small block Chevy

[MikeG]

After a number of years of frustration with my present OB and second failure of the same piston I am exploring options. NOTE, the OB is an OMC seadrive so just slapping on a new OB to the transom is not a viable option.

One option is getting a different boat. Advantage, going to a larger boat. One boat I am looking at is a 22' Sea Ray.

The boat has a small block chevy in it with carb not FI and since I am not up on the I/O thing my questions ares What speed could I expect at WOT, what speed would such a boat cruse at, and what GPH would I be looking at at WOT and cruiseing? I do not know, as yet, the size nor pitch of the wheel so assume whatever is most common.

I know there are so many variables that any figures quoted will not be definitive so I'm only looking for ball park figures to use as a guide.

Thanks

MikeG

[Overcurrent]

FWIW, here are two stern drive boats I've owned for comparison:

1. 1990 Dixie 821 walkaround cuddy. 165HP Mercruiser 4-cyl (224CID) 2BBL with Alpha One drive and 14x19 prop.

Boat was about 3500# wet. WOT was roughly 38MPH, at about 4600RPM. Cruising speed was about 21MPH at about

3100RPM if I recall correctly.

2. 2002 Osprey 24 pilothouse. 270 HP small block Chev 305CID with EFI. (Volvo Penta DuoProp, D4 propset)

The boat weighs about 7100# wet. WOT is about 35 MPH at 5000RPM. Cruising speed is about 3400RPM/24 SMPH at

about 8.5 GPH. WOT fuel consumption is about 17-18 GPH if I recall correctly.

[MikeG]

FWIW, here are two stern drive boats I've owned for comparison:

1. 1990 Dixie 821 walkaround cuddy. 165HP Mercruiser 4-cyl (224CID) 2BBL with Alpha One drive and 14x19 prop.

Boat was about 3500# wet. WOT was roughly 38MPH, at about 4600RPM. Cruising speed was about 21MPH at about

3100RPM if I recall correctly.

2. 2002 Osprey 24 pilothouse. 270 HP small block Chev 305CID with EFI. (Volvo Penta DuoProp, D4 propset)

The boat weighs about 7100# wet. WOT is about 35 MPH at 5000RPM. Cruising speed is about 3400RPM/24 SMPH at

about 8.5 GPH. WOT fuel consumption is about 17-18 GPH if I recall correctly.

Thanks, that's just the kind of general idea I was looking for to start getting some perspective on the situation.

Mike

[kerno]

Mike: As fuel has gotten more expensive, both inboards and outboards have gotten more fuel efficient. Inboards have typically been more efficient because they were derived from automobiles and the two stroke outboards did not have very good fuel metering. But we're now at a point where both forms of propusion are pretty close in their energy efficiency and is comes down to how much energy in BTU's it akes to move how much weight with a given deadrise. As far as I'm concerned, deadrise is more of a varible in the fuel burn than if it is inboard or outboard - unless it is diesel.