23 sceptre performance

[ScottM]

Originally Posted by Snookerd

A 23 Sceptre will get 36 knots with a 225 with a15x15 wheel mounted on the transom or even better on a bracket.

x2 on this.

merch,
Perhaps you've already read some of my past comments, but I'll mention it again just in case...up until Nov '11, my father had a '82 Sceptre with a rebuilt '96 Yam 225 SWS (carb'd) on a 6" jack plate turning a 15 x 15 SS wheel and it would consistently run 21-22 knots at 4000rpm, 24 knots at 4500, and 34-35 knots on the pins (5600). Prior to the Yam, he had a '89 225 Evinrude looper that performed similarly although a tick slower due to engine age and no jack plate.

If you don't care about a top end over 35 knots/40mph, I highly recommend the Yam 2-strokes in either SWS or OX66 format. They have excellent midrange so your cruise is hardly affected by load, plus they're just great motors all around.

[77SceptreOB]

I've got a 1977 Sceptre 23 and I run a 1988 Yamaha V-6 Excel (225 hp) two stroke.

Using a 15" x 17 pitch aluminum prop I get:

Cruise = 30 mph at 4200 rpms burning 11 gph equaling around 2.7 mpg

WOT= 38 mph at 5100 rpms burning 17.5 gph equaling around 2.2 mpg

Those number are per my Lowrance HDS-7 equipped with a fuel flow sensor. All are based on light load run on a large fresh water lake with light chop at 80 degree temperature.

My engine weighs 411 pounds, which is pretty light for its power and size.

From a set up point my cavitation plate is 1-1/2" above my keel at the transom

[merch]

Thanks for all the feedback everyone. I'm really starting to think I definately rode a couple misrepresenting examples.

[Bigshrimpin]

Merch - Where are you in Buzzard Bay? I can show you what a 23cc does with a old 2.4L (175hp) merc.

[merch]

Thanks bigshrimpin. I appreciate the offer. I live in Westport.

[Greene]

Bigshrimpin can also show what a nice custom fiberglass bracket looks like!

[Fr. Frank]

These guys are telling you straight. I used to have a 1974 23' Tsunami (same as the Sceptre), running a single '88 225 Johnson Looper swinging a 15x15 OMC SST prop. Cruise was 23 mph at 3600 rpm, at 2.1 mpg on the NAVMAN. WOT was 38 mph at 5800 rpm, at 1.7 mpg. Motor was mounted on the transom on bottom notch (as high as it would go), water level at cruise rpm was just under ventilation plate, which was completely clear of the water.

Boat previously had twin '86 Johnson 140 hp Loopers under the PO, and his log showed he used to cruise at 4000 rpms at 28 mph, and WOT was 42 mph at 5600. No idea what the fuel economy was or how high the motors were mounted.

IMO. Single 250/300 is the way to go. I prefer Etec and Optimax to 4-strokes, but that's nothing but a preference.

For the record, I have fished many times on a '77 center console jack-shafted diesel. Boat was repowered at Frank Brown's from a gas Ford V8 to an '81 Volvo-Penta 140 hp 4-cylinder turbodiesel, cruised at 18-20 mph, and was WOT at about 26-28 mph. Owner claimed an economy of 3 to 4 gph at cruise, giving it better than 5 mpg. With no trim tabs, it took a while to get on plane, but once there would stay on plane down to about 10-12 mph.

[merch]

You have all restored my hope. Much appreciated.

[jongolds]

I have a 300hp Etec and a large hardtop.
I get about 2 mpg at a about 27mph.
WOT at about 5700 RPM is anywhere from mid 40s to low 50s mph depending on conditions and load.
This is with a 4 blade prop. I don't recall the pitch but can report back on that if anyone cares.

[merch]

Originally Posted by jongolds

This is with a 4 blade prop. I don't recall the pitch but can report back on that if anyone cares.

I care.

Thanks for the feedback.

Tom