Anyone have WOT and cruise speed for 240 WE

El Capitan

El Capitan

Well-Known Member
Jul 9, 2014
3,828
Chicago IL./Vero Beach, Fl
Boat Info
1970 SRV 180 w 2.5L Mercruiser.
2000 Ford Expedition Eddie Bauer
Engines
120HP Mercruiser
Anything late 70’s to mid 80’s vintage w single mercruiser 5.7L/260hp and Alpha drive.

Trying to decide if that power is adequate for my needs.

I’ll have a crew of 3, full tank fuel, full stores including ice. I need to be able to cruise at 25mph on flat calm seas and would like to know if this power setup can exceed 35mph-38mph at WOT.

Thanks
 
Your WOT RPM should be 4500 - 4600 and that 25 MPH cruise speed seems reasonable.

I had a 22 foot cuddly a while ago with a 5.0, 230 HP that planed at around 2800 and cruised easily at 2500 RPM at around 28 MPH and had a top speed in the mid to high 40s.
 
I looked up the dry weight of these classic 240’s and they’re heavy boats. 4400lbs dry! That should put her at 5000lbs easily occupied and wet.

Isn’t a 260hp/350ci mercruiser a bit light in the shorts for this?
 
That is chunky for that length.

The boat I mentioned earlier was light now that I think of it. Maybe 2900 loaded.

I still think with the right prop you’ll get the numbers you’re looking for assuming that everything is in good shape.

My dock neighbor at the time had a 24’ Chaparral with a 5.7 in it and that boat flew and was no feather weight.
 
Last edited:
El Capitan said:
I looked up the dry weight of these classic 240’s and they’re heavy boats. 4400lbs dry! That should put her at 5000lbs easily occupied and wet.

Isn’t a 260hp/350ci mercruiser a bit light in the shorts for this?
Click to expand...
That's really not that heavy, at all, for a 350. I haven't run that specific boat, but have run more than my fair share of boats. That engine, assuming it's healthy, will be totally fine. It wouldn't even be something that I would blink an eye at. Heck, my 260DA was at least a ton heavier with a 350 and I could ski with it easily. Granted, it's not an apples to apples to comparison, but a 350 is plenty of engine for a lighter boat. As long as you aren't expecting it to be a race boat... ;)
 
FullSizeRender.jpg

El Capitan said:
Anything late 70’s to mid 80’s vintage w single mercruiser 5.7L/260hp and Alpha drive.

Trying to decide if that power is adequate for my needs.

I’ll have a crew of 3, full tank fuel, full stores including ice. I need to be able to cruise at 25mph on flat calm seas and would like to know if this power setup can exceed 35mph-38mph at WOT.

Thanks
Click to expand...
We owned a new 260 Express with that engine. The wot spec was was 4200 with the correct prop. Our 260 HP Merc pushed the boat through the water at 21 MPH, turning 3100 RPMs. Running that engine at RPMs above that on a consistent basis will significantly shorten its life. We sold that 1979 boat with close to 4000 hours on it, and the engine used no oil and was still running strong.
 
My 23' 1985 Cobalt has a listed dry weight of 3900 lbs. It had a 260/Alpha I package and at WOT it would just bump 40. Back then I never felt it was underpowered. Now, with all of the higher HP packages out there I really wish it had a big block and a Bravo.
 
sbw1 said:
View attachment 86777

We owned a new 260 Express with that engine. The wot spec was was 4200 with the correct prop. Our 260 HP Merc pushed the boat through the water at 21 MPH, turning 3100 RPMs. Running that engine at RPMs above that on a consistent basis will significantly shorten its life. We sold that 1979 boat with close to 4000 hours on it, and the engine used no oil and was still running strong.
Click to expand...

You were in Freshwater?

I’ll be eventually using in salt a little near shore diving maybe wet a line trolling for dolphin from time to time and crossing over to Bimini, some cruises down to the keys.

I’d have to be slugging along at 20mph though.
 
El Capitan said:
You were in Freshwater?

I’ll be eventually using in salt a little near shore diving maybe wet a line trolling for dolphin from time to time and crossing over to Bimini, some cruises down to the keys.

I’d have to be slugging along at 20mph though.
Click to expand...
Yes. We boat on Lake Michigan. Even at 21 mph we could cross the lake in under 4 hours. It was more of a small cruiser than a go fast boat. You can cover a lot of territory at 20 mph.
IMG_3891.JPG
 
Our boat has an '80 hull and was set up with the 260. It was pretty tired so don't know the original numbers it had. I modified the flywheel housing a bit and put a newer 260 (early vortec) in front of it's pre alpha. It would hit 4450 with a 16x16 prop and the 1.5:1 ratio. Would just break 40 but felt a bit squirrelly there. At 25 I believe we were around 3400. Not sure how much lighter the 240 is, but the old drive was a weak link in ours. Lost it twice in as many seasons trying to run sporty.
 
Thornton69 said:
Our boat has an '80 hull and was set up with the 260. It was pretty tired so don't know the original numbers it had. I modified the flywheel housing a bit and put a newer 260 (early vortec) in front of it's pre alpha. It would hit 4450 with a 16x16 prop and the 1.5:1 ratio. Would just break 40 but felt a bit squirrelly there. At 25 I believe we were around 3400. Not sure how much lighter the 240 is, but the old drive was a weak link in ours. Lost it twice in as many seasons trying to run sporty.
Click to expand...

The 1980 SRV 260 Weekender weighs 5100 lbs dry w the single 260hp mercruiser.

The 1979 SRV 240 Weekender weighs 4400 lbs w same engine.

700lbs should be good for 3-4 mph all things considered.
 
El Capitan said:
The 1980 SRV 260 Weekender weighs 5100 lbs dry w the single 260hp mercruiser.

The 1979 SRV 240 Weekender weighs 4400 lbs w same engine.

700lbs should be good for 3-4 mph all things considered.
Click to expand...
Ours is probably closer to 7000 lbs when we are running around for the weekend. Part of my point I guess was having 260 hp in front of the older drives. Pushing them can get expensive.
 
El Capitan said:
Anything late 70’s to mid 80’s vintage w single mercruiser 5.7L/260hp and Alpha drive.

Trying to decide if that power is adequate for my needs.

I’ll have a crew of 3, full tank fuel, full stores including ice. I need to be able to cruise at 25mph on flat calm seas and would like to know if this power setup can exceed 35mph-38mph at WOT.

Thanks
Click to expand...
You'll hit those numbers easily, mine is an 85 260DA, 6500 loaded, salt water only, same set up. Runs all day 20-22 / 3k rpm burning 4-5 gl/hr, depending on conditions I can stay on plan down to 15 with a 4 blade prop, hits high 30's at WOT, the 4 barrel opens at 3300, so anything above 25 jumps to 6-8 gallons per hour. There's generally too much chop where I'm at to cruise above 30 comfortably.
 
Well I just came back from checking the boat. It has a soft transom. It was so soft I could push it in with my thumb on the outside next to the transom assembly.

Will keep looking v
 
You must log in or register to reply here.

Forum statistics

Threads
113,172
Messages
1,427,833
Members
61,084
Latest member
AntonioJamm
Back
Top