DF300 23 Sceptre
 

Just getting going with the new motor.....

Water test
 

International Marine water testing....

VERY nice!! Post the performance specs once you get it broken in.

Awesome combo!

Sweet!

Very nice Danny!!!!! To me a perfect combination for your boat.

Again my word for the day is....jealous! :)

Sit down, shut-up & HOLD ON........:eek::)

Good for you Danny !
That will be a whole lot of fun going out the Homosassa slalom course ;)

Congrats on a great repower. I guess that will eliminate me running you down in the channel. :D

Looking forward to seeing your performance #s at cruise. I hope it ain't no more than 24 knots though or you'll be exaggerating...

Hey Ken, just imagine what Danny would have bought if the market had a better Summer than the crap it did!! I can see that 400 HP Merc or the Marine7 on his Septre screaming by those Homosassa slalom course rocks with a big smile on Danny's face....that would be fun. :)

Don't get me started! My buddy will be trading in his F350s in the next couple of years and he is already pumping me up on one of those.

I'm not a big Merc fan but a man has to do what a man has to do.....

Thanks brethren! I dragged her to Boynton Friday and it was done on Sat by 12 pm. Intl Marine is fast. I will post numbers ASAP. The Cuddy weight made the 16X20 Zuke prop too much. 5400 max rpm. I have a 18.5 on there, but the installer wanted a 17! I probably need a an enertia prop to lift the bow down the road. With the weight forward I have the same freeboard as with the 450 lb Johnson. It's on the 3rd hole and the plate is even with the keel. The nice motor really makes the top sides look ruff!

I remember almost being run down by Moose! It wouldnt be fun :eek:I do think she will be a sleeper....hopefully low 50's

Dueling "Chain Drive" Zuke Scepters in the river slalom course at Homasassa - COOL!

I have a feeling I need to bring my entire prop collection.
Ding ding.

Nice Danny! Now I know where those commissions went, but rest assured, I concur with your priorities!

The weight of that motor should be a good balance for that boat if you carry much gear in the cabin! Better than the pig iron that some guys have found under the aft deck during some restorations!

If AV plate is just flush with bottom, I bet you can raise the motor at least 1 hole, maybe 2 if you get a prop with lots of cup! The AV plate want's to be above solid water when on plane, but I've learned that it's hard to see it on a white motor, so you might want to stick some black electrical tape on top of AV plate for test purposes!

Very Nice Danny!!

Thanks guys! I believe that the Rake is what can be adjusted with another prop. The enertia sounds like a future purchase!

Usually, due to the difference between the final drive gear ratios between the Suzuki 250 and 300, you can run the same prop on a 300 that a 250 would use on the same hull. I'd ask Kmoose what prop he's running and try one. I would guess your rig should top out around 45-46K (52-53 mph) when run light.

For example, with a GR of 2:29, a DF 250 will have a prop RPM of 1965 at an engine speed of 4500 RPM. A DF300 with a GR of 2:08 will have a prop RPM of 2163 at the same 4500 engine RPM. So a DF 300 is spinning an identical prop roughly 10% more RPM at any given engine RPM compared to a DF250..

I am very surprised it didn't pull the 20 even with the different gear ratio. Mine pulls a 20 to 6k+ depending on load but I guess the difference is considerable.

I would strongly recommend the addition of a 10' CMC manual adjust bracket to your set up. It gives you infinitel adjustment as well as enhanced performance by allowing you to run the motor almost 2" higher.

I'm with ya Moose! I went with the 6" manual plate because my engine was spraying water all over the place because the cavitation plate was too low, it's was on the middle hole. I now have the cavitation plate at 1 3/4" above the keel and it's perfect. Really easy to dial in the engine height with this set up. Here's what I bought....

http://www.ebay.com/itm/Jack-Plate-J...jSQRVQ&vxp=mtr

When you see this product you wonder how they make them for this price. Danny would have to go the next size up which is up to 400 hp. He's in the big boy league!!

This is the one I use and it is good to 300 hp. The price is high on this sight but they can be found for around $300. Best investment you will make.
http://www.proboatparts.com/cmc-manu...et-back-61012/

Thanks Don and Ken-I was totally surprised to hear that the 20 was too much. I need to run it. May be they were trimmed too low??? It show handle the load at least as good as the 250, right!? That manual plate sounds good.

I've looked at many many reports of repowers with the 300 Suzuki. 16x18.5 seems to be the ticket on almost every hull in the 22-26ft range. One boat used a 16x20 but I think that was an older 23 Contender.

I'm getting my White 300 installed 11/13. Cant wait! My buddy is repowering his 24 Proline with a black 300. Right now he has a 225 Yamaha efi, tops out at 40 mph.
When I get his final numbers I will post them. Luckily my shop is a stones throw from Leading Edge Propeller if I need some cup.

Hey Capt., didn't I meet you quite a few years ago with Nick and Frank? Any chance you're coming to the rendezvous at MacRaes?

Like Moose Im running the 16X20 on my 23 with the 250, and could easily go to the 21 pitch but happy with the performance as is. but my boat is a center console.

Danny, I think I'd focus on getting engine height correct before you start changing props. You might pick up some rpm by raising motor and reducing LU drag.

Engine friction losses may also decrease a bit once you complete break-in, giving you a bit more HP at the prop. Although the E-TECs don't require a break-in and don't seem to experience any performance change once they get past the initial extra oil period (2-5 hrs >2500 rpm), some 4-stroke automotive engines typically run a little better after they "loosen up" and the rings get seated. Didn't notice any changes after break-in on my BMW, but those engines are bored & honed with head plates at the factory to insure perfectly round bores on new engines after assembly. That's an old hot rodder trick not done on most high volume production engines, where the bores distort slightly during assembly due to head bolt loads, creating high/tight spots that have to be worn down during break-in. Don't know if Suzuki machines their outboards with head plates, but that could determine if you gain any hp after break-in.

After giving this some thought and reflecting on Dan's (Headhunter) post I think there must be a glaring issue somewhere. There is just no logical reason a bare bones version of my heavy sled with 50 more horsepower doesn't turn at least 5800 or more WOT. It doesn't pass the smell test nor make any mathematical sense as well. If it was me I would be looking to see if the throttle body linkage is opening up all the way when the fly by wire hammer is put to the wood. I'm not sure that can be accomplished with the engine not running but I would put the key to the on position and check. If not I would get a buddy and pull the cowl and run it checking the same. Something is wrong and it isn't break in restrictions or oval cylinders. Maybe the ECM has a throttle limiter for a break in duration but I haven't heard on anything like that but maybe on the new "AP" models it exists. In any case your installer should be on top of this and answering these questions instead of dropping prop size that will mathematically drop your WOT speed below 40 kts.

Danny, If you want to talk to the best available Suzuki expert on the planet give Robert at Precision Marine a call. 727-518-2151 He would be more than happy to give you assistance over the phone.

Ken – I took the boat out today for additional break in time. I have about 2 1/2 hours. The most RPMs I've gotten to is 4000 at 25 knots. That is pretty close to what the pro line in their boat test section shows at 4000 RPM with the same prop 18.5 P. I think the motor could come up one hole. I will know tomorrow.

On to more serious issues.......you now have to change your picture. :)

Yessir! Thank you.

Finally got past the break in restriction to be able to go WOT. Max is 5650 rpm @ 38.5 knots. Definitely dragging arse! Tell me about those manual plates.

There is more going on than what a plate will fix but it will help. Were you able to confirm the throttle body linkage is allowing WOT?

At 5650 engine RPM you have a prop RPM of 2716. On the Moose's boat, he would have to be turning 6219 engine RPM to match your prop RPM of 2716.

His boat will do 38.5 K around the same 5650 RPM that your boat is doing but at only 2467 prop RPM. You are spinning an identical prop roughly 10% faster to achieve the same speed with no wind catching top on your boat. Hmmnnnn..


I'd check the prop first. Just because it looks good doesn't mean it is good. Could have been re-pitched before it came to you? etc.

If the prop checks out, raise the motor a pin hole and retry. My experience with the 23 hulls show you need to be an inch higher than the deadrise point, maybe an inch and a half.

I'm not a huge fan of bolt on brackets but will admit that Kennys set up performs great. If after verifying the prop is "right" and raising the engine doesn't solve your issue, I'd def consider bolting on a 10" set back bracket.

I don't know Danny, the best I've ever had my boat in perfect conditions, light load and really skint back was 51 mph on the GPS. You are at 44 mph (38.5 knots) so I would think you should be able to get to the 43 knots/50 mph with a light load, perfect conditions.

The idea behind the jack plate is you can easily adjust the engine so the cavitation plate is even with the water and parallel with the water as it comes off the transom/hull's edge. Remember the water comes up from the bottom edge of the transom at around a 10 degree angle, I'm guessing on that angle, might be more, so if the cavitation plate is too low the water, the water is not hitting on just the sharpest point of the gear case causing extra drag. Look at the "streamline" design at the front of the gear case at and below the cavitation plate, now add the two to three inches above that which is also plowing through the water if it's mounted too low.....more drag. That's my theory and I'm sticking to it.

That seems to be the consensus for some of us discussing it offline. As Bushwacker suggested it is best to get the motor up high enough before the prop swapping starts. I would love to see a pic of the motor down in running position and a straight edge coming of the keel. My guess is the motor is more than a few holes too low and will require a bracket like I linked to get it up where it needs to be. They even make one with half the set back of the 10' if putting it back there is of any concern. Considering my 250 is a 30" motor his is probably close to the weight of mine minus the center section weight and shouldn't care either way.

Would you recommend the jack plate on a 23' Sceptre that already has a Hermco bracket? I am already concerned about maneuverability at low speeds and so I am concerned that an additional 10" will just make it worse.

Straight edge
 

It looks to be above the keel an inch already?!

Weekend picture
 

No visual of anti cav plate

Running #2 pic
 

Plate running

Pic #1
 

Plate

Put the level on the bottom of the keel and extend back just far enough to see the AV plate with both parallel.

Hey Lamont come here you big dummie.
Esther, your so ugly I could stick your face in dough and make
Gorilla cookies.