new member, wanting to compare performance 23cc
 

hello all, I just purchased a 23 cc 1998 back over the winter.
not a classic but the boat only had 8hrs on new power
it is powered by twin 150hp etecs, I say the boat rides very nice. did alot of work over the winter rewiring and taking care of the hull.

seems to me that this boat with 300hp should be making better speed on the top end.
at 3500rpm I am running 29knts
at 4100 35knts
at 5000 wide open 38knts
I am reading speed via GPS and could be a problem with GPS speed

if anyone has a similar boat and power, please do me a favor and post some perfomance stats of your boat

thanks

Re: new member, wanting to compare performance 23cc
 

Sounds about right from others I have seen,it would be faster with a single 300, even a single 250 in my opinion. My single 225 on a very heavy 23 Savage produces roughly the same top end.

Re: new member, wanting to compare performance 23cc
 

I used to have a 23' with twin 150 Yamaha SWS's. It would top out around 44 MPH. Since the engines were carb, I would avereage about 1.6 miles per gallon.

The SeaCraft hull rquires power to push it. I have a friend who has a 23' Parker SE CC. He can push his boat with a 200 HP, and can move quicker & gets better mileage than a 23' SeaCraft with a 225HP.

I now have a 23' SeaCraft with twin Yamaha 200 HP OX66's. This boat I can push into the mid 50's.

Any idea on what your RPM's on the ETC's should top out at? Have you considered different prop's?

Peter

Re: new member, wanting to compare performance 23c
 

thanks for the input
the motors are rated for 4850-5500 flat out
so I feel I am at the largest prop I can fit without lugging the motors
have yet to get any kind of fuel burn numbers and efficiency stats out of them
they seem to purr along at 3500 rpm
would be nice to find someone with the etecs on the same boat and see if they run the same.

Re: new member, wanting to compare performance 23c
 

'73 23' CC w/Alum. bracket/250 Yam. OX66 w/17P prop...low-mid 40's at 5500 rpm. avg. fuel burn is 2mpg if you don't keep it pegged.

Re: new member, wanting to compare performance 23c
 

dropping 2" in pitch would probably help out on the hole shot and top end - that should get you about 5400

Re: new member, wanting to compare performance 23cc
 

That's pretty good - 44mph...considering you've got 900 lbs on your tail end. I presume you have trim tabs. Different prop, depending of course on what your current shape is, might give you more stern lift. Lower pitch might add some rpm, but I think you're past your speed gains curve rpm wise. If you have a a t-top that adds a little drag, too.

Re: new member, wanting to compare performance 23cc
 

I think a couple of Power Tech 4 blade stern lifting props would get you better mid range performance, especially on fuel. That is a lot of weight on the back of that boat. I am running a Honda 225 on my SeaCraft 23WA and run better than that. I am no speed demon, so 35-3700 RPM at 27 MPH suits me just fine. I think WOT gives me 42-44 MPH.

Re: new member, wanting to compare performance 23cc
 

Gary how do you like the power with the Honda? I have been thinking of going with one, and have seen several 2-3 yr old ones in the 7-8k range. the last Hondas I had ran fine at over 5k hours. My biggest concern is performance with 3-4 divers and 8 tanks.

Re: new member, wanting to compare performance 23cc
 

I really like it. Once I got rid of the proposing by raising the engine and putting on the Power Tech 4 blade stern lifting prop, it performs super. Great fuel economy at mid range, which is where I run 99% of my time. We just have too much junk in the waters here to safely go much faster.
That is a lot of weight, can't offer much advise there.

Re: new member, wanting to compare performance 23c
 

thanks for the replies
what makes a stern lifting prop different than a regular three blade
I assume it creates some lift, but how does it do it?
different blade configuration?

Re: new member, wanting to compare performance 23c
 

I guess it lifts the stern of the boat because that is what it did for me after I installed a 225 Honda which was much heavier than the old Merc 200 2 stroke. FrankFrank is the prop guru here , seach for his posts.

Re: new member, wanting to compare performance 23c
 

I know all the bow lifters are higher rake props. I believe Low rake props provide more sternlift . . .

Re: new member, wanting to compare performance 23c
 

Mercury has a very good primer on prop technology here:

Prop Technology

As has been mentioned above, Fr. Frank is the resident X-purt. The Merc site will help you understand some of what he says about props.
Dave

Re: new member, wanting to compare performance 23c
 

Tim is right on here.

High continuous rake props provide lots of bow lift. Low continuous rake and Progressive rakes props tend to provide more stern lift. Generally speaking, 4 blades also provide much more sternlift than 3 blades.
In general, one of the rules is that the greater the proportion of forward thrust created near the point of rotation, which is the hub of the prop, the greater the stern lift.

Of course there are a great many other factors which affect all of this, which is why there is no substitute for putting a prop on and giving it a try. The experiences of so many members here on CSC who have tried so many different props is a great resource.