checkmate starflite

[jrf2800]

i just got this boat rigged with mercury laser 220 hp, hydrolic jackplate and i just got a 26 chopper prop, what should i expect as top speed from this set up, i rev it out at 5800 rpm but i must get air ?

[pyro]

65 seems to be a typical top end number for 200/"220" hp, maybe 70 with really good setup. Your numbers currently indicate around 65 at 15% slip, a typical slip number for a chopper on a heavier boat like such.

Cut open the compartment up in the bow and remove the 100 lbs of soaked foam from up there if it hasn't been done already. There's probably more hidden in other places too.

-Chad

[jrf2800]

thanks for the info, seems right as i went out and i thought i was in error but top speed i got was about 63 mph...i guess your knowledge is above what i thought i would get from this, strange though, i get 55 from a black max aluminum 23 pitch and only get 63 from stainless chopper 26...what dont i get here ?

[pyro]

sounds about right. Get all that hidden dead weight out of there and you'll see mid to upper 60's no problem. How much setback is your jackplate? The Starflight likes 12" or more, if the transom is healthy.

How deep is the motor?
The aluminum prop will just slip like hell at the heights that chopper was designed to run at.
Calculate slip here:

http://www.rbbi.com/folders/prop/propcalc.htm

[jrf2800]

what if i leave the boat as is, and not cut out overload, what can i get out of it, maybe differ from cutting out weight to getting more HP, what are your thoughts on this...if i got 50 hp more, what would be the proper thing to do ?

[pyro]

You're not going to see another reliable 50 HP out of that motor, so forget about that. If you want more power, put a 3.0 300 promax or 300x on it.

These hulls, like many others, are notorious for holding heavy water-soaked foam. The weight doesn't belong there. Make sure your transom is solid also.

[jrf2800]

what do i have to do to cut the weights as you say, how do i do it, explain to me in detail please as i wish to do it right and only once, thanks

[pyro]

I have no idea, I'm just repeating what I've read time and time again here.
The area inside the tip of the bow seems to be a trouble spot with this model. I guess there's a carpeted wall at the front of the bow, cut into it and remove all the foam from behind it, as it's usually soaked with water.

Look for some fresh replies tomorrow night...

[zachp13]

Check out this site http://checkmate-boats.com/forums/index.php and search for foam removal.

[illMATTic]

yes, you need to cut a hole in the front wall of the boat in the stabbin' cabin. the whole area is filled with floatation foam . it is garanteed to be 1/2 full of water. mine was. it is dirty work BUT it will net you a good 3 MPH. just cut a hole in the wood, hack away at the wet foam and throw it out.

[aaronmt73]

MY stock 87 yamaha 225 pushed my starflite to 74.3mph, its all in the setup. I would remove the front bow foam run a 12" jackplate and a 25 trophy plus I tride all different props, startflites need the smaller diameter prop to come out of the holeand be able to run the larger pitch.

[wca_tim]

in my similar model... foam in the front was dry... alsu the foam under the deck when I rebuilt the stringers... the flotation boxes in the back (i/o)? struck water in one of them... easy 100+ pounds. the other one was dry.

[jrf2800]

i am wondering, could all this weight affect so much ? i have a top spped of 61 now, running mercury laser 220 with jackplate and 26 chopper ?...i think i should get more as i rev 6000 rpm with it...

[wca_tim]

If you want to see how much a hundred or so pounds of dead weight will change things... get a fat chick to sit in the back and see what your numbers are...

[jrf2800]

i drive alone to test lol and i scared myself yesterday just putting the jackplate up top as the boat wanted to scream right all the time....just wondering why i just got 5 mph from an aluminum 23 pitch to a 26 stainless chopper ?, just thought more as i got the same rpm, 6000