What are the REAL TomCat 255 performance numbers.....PLEASE!

[Gowaltergo]

Will be buying a used 255 THIS MONTH!
Just sea trialed a 2006 with Honda 150's with 900 hrs
Performance stinks despite clean bottom virtually empty
And only 40 gallons of fuel onboard here are the numbers:
Actual. Boat test and factory says
Rpm mph. Should b
3500 21.3. 26.5
4000 22.5. 31.0
4500 23.7. 35.4
5000 26.5. 40.0
6000 36.1. 47.3

Can anyone out there let me know what they are experiencing in real world
Thank you soooo much!!

[Discovery]

How are the Honda's propped? We use stainless 3 blade 17" pitch props, and get results about what you showed, but fully loaded with gear , fuel and water. I usually cruise at 3800 to 4000 RPM and would be running around 22 to 23 MPH. Burning about 9 to 10 GPH.

[rogerbum]

[Westie]

Those numbers seem very low to me and I'm running twin 140 Suzuki's with a full load and bottom paint.

I typicall cruise at 4000 rpm which produces a speed of 25 to 27 mph.

With 20 more HP and a lighter load, I could imagine the factory specs are close.

[redbaronace]

Seems pretty good given that the factory numbers are likely with brand new engines and ideal conditions.

If you are wanting more performance, you might need to find one with 175 suzukis swinging props mated for the top end you are seeking.

Having had now 3 Tomcats, I can say that each handled differently depending on engines, HP, weight of contents, bottom paint, permatrims, etc.

The bigger motors will typically weigh more than the smaller HP outboards. This will effect your fuel economy.

If you really want fast, the brand new engines coming out seem to have shaved some weight. But 2 new engines for the Tomcat will cost you some $$$$.

All considerations to make. For most folks, 40MPH is plenty fast.

[rogerbum]

Also, I guess I'm not quite understanding the need for speed well above that. You've stated earlier that you goal is to beat your previous record for doing the great loop. You mentioned that your record is 7 weeks and 3 days (or 52 days). Assuming a route of 6500 miles (the distance ranges from 5000 to 7500 depending on route), 6500 miles/52 days = 125 miles/day. That's 4 hours/day at 31-32mph. What fraction of the loop can be run at high speed?

[cmetzenberg]

[Foggy]

Walter go

1. Get a prop job or

2. Consider another boat

My 26' Venture will do 36 mph (WOT) with twin 90s
and burn somewhere less than 30 gph.
I turn 13.5 x 15 Al props.

A clean bottom is always good and may help.

Aye.

Grandma used to say, "Wider is not always better."

[thataway]

There is no question in my mind that the Tom Cats with the Suzuki's are going to be faster. I sea trialed A Tom Cat with the 150 Hondas and then 150 Suzuki's. I found numbers similar to what you reported, and others reported with the Hondas--and like the second set with the Suzukis. The Suzuki can swing a larger diameter prop, and with their gearing, will have considerably a higher pitch prop. 4 blade props, with the counter rotating prop on the Starboard, instead of the port as in most twin engine boats. This gives more compression of water in the center, and stern lift. When my boat was new, and light, we were very close to 50. Even with the Air conditioner, freezer, microwave, and 3 extra batteries we were running in the mid 40's.

So if you want speed, get on with Suzuki's.

[gulfcoast john]

Hi Walter,
I believe C-Dory just used the BoatTest Honda stats, and did not commission any additional testing. If I recall, Discovery WAS the test boat. So you're looking at a single test day with engines that might have put out at the higher of the 15% or so variation among different engines from the same factory on the same day. I too am close to your stats, except in Heavy Cruise Mode with full water and fuel (that's 900lb fuel alone) running cheap 4 blade 17 pitch aluminum SOLAS props and rough bottompaint. I need to 'burnish' it. Agree with all above, especially rogerbums terse 'propping or trim or both' and Dr. Bob 'Suzuki for speed' diagnosis.
Possible issues include:
Does the seller have evidence that when new it met the BoatTest specs? If not the engines may be mounted too low; AV plate should not be underwater at cruise. Or engines putting out the lower end of the 15% normal variation.
Props may look fine but be out of spec enough to be the cause. Scanning/specing would give you the most bang for the buck here at $100-150 each or so.
The 255 likes a LOT of trim up at speed...takes some getting used to...agree insufficient trim up at 6k could be the cause. I run at 3.5+ bars out of 5 on Yamaha trim gauges.
Transom sounder in a poor location could be aerating a prop...mine is.
Run only ethanol free gas, it contains more energy...you can bet the BoatTest crew didn't dilute their gas.
With 900 hours, the engines may be just a bit tired. Least likely as Discovery is of same vintage.
Be sure the engine bracket isn't full of water.
If you can swing it consider Peter's 2009 "Destiny II" with 175HP Suzi's (400h) now that he's selling it for only 98 Boat Units with Wefings Float On trailer. That is one beautifully equipped fast cruising Tom Cat. I'd buy it, but unlike redbaronance I can't justify owning 2 Tom Cats at the same time.
Hey Dr. Bob, you could at least let Maria LOOK at it!
Hope you can find the missing performance with a simple cheap fix. If not , it's still a great, stable, comfortable, forgiving boat that will, to quote our Surveyor, "be around a lot longer than you two." And we paid him over $400 for that opinion.
30mph on the water for recreational boaters in non emergent situations is fast enough. It's not a road...if/when you hit the barely submerged invisible deadhead or sunk container, 30 MPH is too fast.
I am an outlier here in many respects, including that I would be more interested in the story behind 'The Slowest Loop Ever Done' than the fastest. Oh, well.
Good luck!

Cheers!
John

[Gowaltergo]

Thanks everyone for sharing your thoughts!
I received some interesting advise today from
The factory who actually spoke to their Carolina dealer, who
Suggested a bigger diameter 15x17 alum which should
Provide 40 mph at 5900 and if I use a Stainless version it should do
As much as 44 although at 5500-5600 rpm.

I'll try it in a few weeks after I close and let u guys know
What happens

[redbaronace]

Our Tomcat with Suzuki 150's was doing 42MPH moderately loaded. Im not sure if different props could squeeze a few extra MPH.

Given that this is plenty fast enough, we have no interest in changing props to find out.

[BrentB]

Check OBs height. Maybe they are mounted too low.

[kevin ware]

We own your same set up. A 2006 Tom Cat 25.5with bottom paint and Honda 150s having about 400 hours total time.

I have charted the speeds at different fuel burns and found them to be consistently lower by 3 - 4 knots than shown in the sales literature, so suspect the factory was a bit generous in their speed estimates.

But, having said that, I have also found the boat's speed is very senstive to the following:

1. Engine control software. Honda engines are fuel injected electronic wonders, but if the software gets even slightly out of wack, it really effects power output. Take the engines to a Honda dealer and have them check it out with their computer. The needed computer software seems to be proprietary to Honda, and so only their authorized dealers have it. Once on the computer, it is easy to re-set the engine controllers electronically. Cost is $200 or so. Would certainly do this before changing engines.

2. Propeller size and condition. Not all the boats recieved the most efficient combination of engine and propeller size and pitch when new at the dealer. Take a careful look at what you have, supply that information to this web site and get some feedback from what others are running. (We have a set of high altitude props, an aluminum set that came with the engines, and a stainless steel...don't have the numbers here). Of those, the SS set work better than the others in salt water at sea level.

3. Height of engine at transom. Look carefully at the bolt patten on the transom mount and see how far "out" of the water your engines are. In our case, they were mounted a couple inches too high by the dealer when new. Among other things, this occassionally caused the engine cooling water intake to be inadequate, causing an over heat alarm. It took some time to figure this out and then lower them 1 or 2 bolt holes, which seemed to improve speed by a couple of knots and also resolve the cooling problem.

4. Weight of the boat. Cats of all types are very weight sensitive vessels. You will easily see a 5 or 6 knot speed penalty just by having the fuel tanks and water tank topped. At about 12 gph (which we figure to be average with speeds in the mid 20s mph), you have nearly 8 hours of fuel on board, yet most runs are rarely more than two. If you are looking for speed, manage your fuel load with this in mind. Same with fresh water.

5. Water in transom engine mount. The transom mounts have a hatch in the top on each side that is not adequately water proof. In certain conditions you can easily accumulate 40 or more gallons on one side or the other. That is in excess of 300 lbs, all as far aft as you can get, and it will really slow your boat down. There is a drain plug for each side. Pull it and see what you get.

6. Boats longtitudinal center of gravity. Weight aft seems to have more of an adverse effect on these boats than one might expect. I have moved my house batteries forward, and keep as much on board 'junk' in the bow lockers as possible. Also have anchor chain, which shifts the longtitudinal CG forward a bit. All this seems to help.

7. Altitude and fresh vs salt water. Our boat turns into a pig at high altitude and in fresh water. Will not even plane with the props that work just great in salt water at sea level. When in fresh water we change the props to a smaller size and pitch, and give the engine computers a couple days to 'adjust' to their new environment.

We have owned a number of boats over the years, and lived on board and cruised a Nordhavn for a while. Although the Tom Cat has some design issues, in the main we really like the boat, and have found most other owners feel the same way. You will get lots of useful feedback from those folks if you inform the group of your prop combination and engine mount configuration.

Kevin Ware
Tom Cat 25.5

[Alok]

My moderately loaded 2006 Tomcat with 150 Suzukis, bottom paint, and bimini would top out at 45 mph.