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nickhedstrom
05-12-2012, 02:49 PM
93 Starflite 21', 08 250xs with sporty 1.62, 4B 27 pitch hydromotive labbed ($1,100.00 prop), getting 70mph on gps at 5300, cant go any faster cause of bad chine walk, if i trim it down i get no speed, could different prop help or could the sporty lower unit be hurting the performace, tested with 1 passenger and had him move to different spots in the boat and same results. Any ideas?

denis leblanc
05-12-2012, 08:06 PM
93 Starflite 21', 08 250xs with sporty 1.62, 4B 27 pitch hydromotive labbed ($1,100.00 prop), getting 70mph on gps at 5300, cant go any faster cause of bad chine walk, if i trim it down i get no speed, could different prop help or could the sporty lower unit be hurting the performace, tested with 1 passenger and had him move to different spots in the boat and same results. Any ideas?

Hey!! do you have a set back? a hydraulic transom jack?

I had the same problem with mine I run a pulsar 20.5 ft. with a 250 XS so I started with moving the battery and oil container on passenger side and install solid motor mounts on the engine with just that I was able to run up to 75mph and then it started chine walking after I check my hydraulic steering for tightness and fix that then I got up to 77mph and from there its all up to time behind the steering you play with the jack and trim until you find the best set-up once you determine the best set-up then you start to compensate when boat chine to the right you steer left when it chine to the left you steer to the right the faster the boat chines the faster you steer left and right until the boat is 90% out of the water then it gets easier and you should be between 80 85mph if you get scared you back of the throttle then the boat will sit and then you start over like I say it takes time lots of hrs. and then it becomes like ridding a bicycle

A 10in. set-back and a CMC hydraulic jack is a good start

Just remember get a water pressure guage and keep it at 7lbs. and do not jack to high you will get a blow

kalugs22
05-13-2012, 02:11 AM
Funny you post this, we just ran my dad's 88 starliner today for the first time with a 250 ProXS and a 27p Labbed Trophy Plus with a torquemaster and 7.5" of setback/hydraulic jack plate. The best I could get tonight was about 5400rpm and 75-76mph. I really didn't get much chine walk at all, I ran wide open next to my buddy in his 21' pulsare for several miles. I think the 27 is to much prop for that boat, we have a 24p Fury we are going to try next and see what happens. If you don't have any setback, get some and I would do atleast 10" we are going to add more to the liner. The sporty is probably not hurting you but it's also probably not helping. I can run that torquemaster at the pad and not loose water but it can't carry the boat at that height. There's a thread on here you can search for that is all starflight/starliner speeds and setups. Good luck!

nickhedstrom
05-13-2012, 10:28 AM
it has 5" built in to the boat, 5.5" hydr jack plate, and Bobs 6" set back bracket. The 6" set back bracket i just installed this winter and it got 5 mph faster, it used to get bad at 65 mph now its 70 mph. The motor has solid motor mounts and the steering is tight. One thing i noticed about the steering is that i cannot turn the wheel when im WOT, so when u say boat goes left turn right i cannot do it cause its too tight. That doesnt seem right does it? I have to back off the throttle to turn the wheel.

nickhedstrom
05-13-2012, 10:33 AM
I can tell the boat wants to go cause if i have the motor tucked all the way in i only get bout 60 mph but as soon i start trimming its picks up speed quickly. The more i trim the more speed i get until it walks then i gotta back out.

nickhedstrom
05-13-2012, 10:35 AM
Has anybody had wet foam not only in the bow but the sides towards the transom? Mine is dry in the bow but dont no bout the sides.

nickhedstrom
05-13-2012, 10:38 AM
Would like to try a 25p or 26p 4B Trophy if i could get my hands on one.

kalugs22
05-13-2012, 10:50 AM
What kind of height are you running it at? I noticed yesterday if i had the motor all the way down with the jp and was wound up the steering was very hard but once i raised it up it got a lot easier. I will have to measure the height off the "V" and ill let you know what it is. I'm guessing around 2.5" And yes the more trim the faster these boats go, mainly since they aren't padded they need a little more help, it was fastest when I ran the trim all the way to the stop. As far as the foam goes, you could take a hole saw and drill some test holes and see what it's like. If you don't have any rotten floor then your probably ok. It would be hard for water to find a way in to without going through the floor.

atc250r
05-13-2012, 10:58 AM
I wish I could help you with a prop but I can say that I find when I run the propshaft around 3" below the pad or less I start to get that really tight feeling on the steering wheel but only when I try to turn left, it will go right no problem. I find I don't lose any speed when I run it at 4" so I usually just leave it there. I am running dual cable, 5.5" of set back, and a Raker 3 blade. I find the steering a lot easier when I run the 4 blade I have.

John

nickhedstrom
05-13-2012, 03:17 PM
2" below the V, gonna try to go higher but im sure i did and didnt make much difference.

nickhedstrom
05-13-2012, 03:20 PM
The steering is so hard at WOT that its slips, i mean the steering wheel will turn but the motor doesnt.

atc250r
05-13-2012, 05:28 PM
On a Flight/Liner there is no point in going that high. It has no pad so it will not "fly" light a padded boat will. The prop needs the bite to lift the bow and get the hull out of the water.

denis leblanc
05-13-2012, 09:54 PM
On a Flight/Liner there is no point in going that high. It has no pad so it will not "fly" light a padded boat will. The prop needs the bite to lift the bow and get the hull out of the water.

Yes you are right you need the prop to bite to get bow lift

denis leblanc
05-13-2012, 10:05 PM
The steering is so hard at WOT that its slips, i mean the steering wheel will turn but the motor doesnt.

What kind of steering you have? if you are runnig dual right guide steering on the same side you will have problem to steer you need a dual right guide one on each side going down to the motor and a special bracket that goes on each side of motor this way is the only way to steer at high speed. Mine is a hydraulic steering it is like power steering and i can steer easily at any speed right or left if you do not have that set-up your speed will be 70mph the other thing you can do is get the prop to a prop shop and get it cuped up more and you can run the motor higher and get less steering drag if you can not get the steering to loosen up you will not be able to drive through the chine

denis leblanc
05-13-2012, 10:32 PM
Would like to try a 25p or 26p 4B Trophy if i could get my hands on one.

If you have a tight steering try a 3B prop it is not as stable like a 4B prop but it may give you a loose sterring to drive through the chine a 4B prop will give you good hole shot but less mph. a 3B will give you more rpm and mph you have to find the prop that gives you the closest to the power band of the motor(6000 to 6300 rpm) sometimes less pitch will give you the rpm you are looking for with less steering drag

like I always say you want to play you have to pay ha ha!!

nickhedstrom
05-14-2012, 09:50 AM
it is hydr. steering but not sure what your talking about with the type, the 2 hydr. hoses connect on the right side of the boat/motor. I have seen other types that 1 connects on the right and the other connects on the left. This prop was made with lots of cup in it and it does get the bow up.

Philster
05-14-2012, 02:37 PM
Steering tends to disappear when you are too high on motor height in a V bottom boat.

The whole V is a rudder. On a flatter bottom boat, it takes less bite to steer. On various boats that skim across the surface, so can the prop. On a true V, the prop needs to get lower because it will require more bite to move that V which is in the water.

Your setup screams 'too high'. "Chine Walking a V Hull" and "My V Hull Won't Steer". In the book of "Is My Motor Too High?", it's chapters 1 & 2.

denis leblanc
05-14-2012, 08:25 PM
it is hydr. steering but not sure what your talking about with the type, the 2 hydr. hoses connect on the right side of the boat/motor. I have seen other types that 1 connects on the right and the other connects on the left. This prop was made with lots of cup in it and it does get the bow up.

Well ok then you say you have a hydraulic steering how easy is it to steer from right to left with engine in nutral you should be able to turn with one finger if not check the cylinder at the motor bleed the system if you have to next I would try a 25p x 13 tempest plus 3b. if you have to much rpm try a 25x13.5 or a 25 x 14 and the a 26x13 ,26x 13.5 , 26 x 14 , I know its hard to find these props but if you find a prop shop that is willing to help you and he knows you will buy the prop from him once you found the wright one he will be happy to help because this is gould archives for his shop

denis leblanc
05-14-2012, 08:34 PM
Steering tends to disappear when you are too high on motor height in a V bottom boat.

The whole V is a rudder. On a flatter bottom boat, it takes less bite to steer. On various boats that skim across the surface, so can the prop. On a true V, the prop needs to get lower because it will require more bite to move that V which is in the water.

Your setup screams 'too high'. "Chine Walking a V Hull" and "My V Hull Won't Steer". In the book of "Is My Motor Too High?", it's chapters 1 & 2.

Very good example here!! this is why you have to try different props and if you get to run your starflite 21ft. in the 80mph you will be one of the first to do it

denis leblanc
05-14-2012, 08:45 PM
Hey man !!! its too bad you do not live close to me in Ontario Canada because I would love to help you set-up your rig to run in the 80 plus I have a place here that we can try all the props merc ever made from chopper props to cleaver props to name it we will get your boat to go beleive me and the problem is with the new engines you cant fit any prop you want because of hub size but everything can be modified

And again like I say you want to play you have to pay

denis leblanc
05-14-2012, 08:50 PM
By the way nice boat Philster, the colour are awsome very nice :cheers:

atc250r
05-14-2012, 08:51 PM
Very good example here!! this is why you have to try different props and if you get to run your starflite 21ft. in the 80mph you will be one of the first to do it

All due respect Denis but he would definitely not be the first Flite running those speeds.

Bblades does a prop exchange program and a lot of people say good things about them.

John

denis leblanc
05-14-2012, 08:59 PM
All due respect Denis but he would definitely not be the first Flite running those speeds.

Bblades does a prop exchange program and a lot of people say good things about them.

John

Thanks John I know these Flite can run in the 80 plus its just in my area no one wanted to take the time and money to run them at that speed to them 70mph was all good

atc250r
05-14-2012, 09:11 PM
80 with that 250 will be hauling the mail. It'll be a tough goal to reach.

denis leblanc
05-14-2012, 09:40 PM
80 with that 250 will be hauling the mail. It'll be a tough goal to reach.

I know but it can be done all depends on how crazy the driver is

atc250r
05-14-2012, 09:58 PM
Back in the day there were some with 300 V-8 OMC's that ran upwards of 80 and from what I read on here they are pretty stable at those speeds for a boat that was probably never intended to run that fast. Unfortunately it isn't the most efficient hull for high speed running but it does do very well in some pretty heavy chop for a relatively small boat.

If the set up is right then the driver doesn't have to be crazy. ;)

John

nickhedstrom
05-14-2012, 10:42 PM
Thats the prob, no one around here stocks any good props. You would think living here with a big river and lake Michigan at my door step it would be props galore plus a ton of inland lakes. BTW it steers with one finger in neutral. I talked to a guy that has same prop, motor, boat,set back, but a torque master and he gps 82 to 85 mph. I could have left my 200 on it and got dam near the same speed. :pissed: I wonder how much difference there is between the prop i have and a 25p 4B trophy?

nickhedstrom
05-14-2012, 10:45 PM
When i meant same speed i meant speed im getting now with my boat (70mph GPS)

Mark
05-15-2012, 10:01 AM
Nick
You are just set up wrong. It can be fixed.
The 27p prop is way too stiff for that setup. I am surprised you are getting even 5300 rpm. If you have 1.62 gears you are also seeing 17% slip. Way too high. If I had to guess, you are trimming the motor right up to get more rpm giving you massive slip and making it unstable at speed. Your holeshot must be brutal.

If you really have a 1.62 gear case you should be running a 23p prop at most. Trophy is a good bet for these hulls. 2.5"-3" below the V and you should be good for 75 MPH.

I have a 250 Etec and run a 25p Rev4. Good for 74 mph. I would think the 250xs should be faster.

Mark
05-15-2012, 02:15 PM
One other thing. The hydromotive 4B although a great prop is probably made for a high speed bass boat like a Bullet. They have numbers stamped on them as well as the model. If you phone the factory they will tell you what configuration it is. The Quad IV X O/B which is made for outboards came in 3 styles. http://www.hydromotive.com/int_quad4X_OB.html Most often they are class A or B and are made for surfacing situations and very light hulls. Unless it is a class C it will be a dog on a Starflite. Aside from being too much pitch you, are fighting against that prop instead of it working for you.

denis leblanc
05-15-2012, 10:19 PM
Nick
You are just set up wrong. It can be fixed.
The 27p prop is way too stiff for that setup. I am surprised you are getting even 5300 rpm. If you have 1.62 gears you are also seeing 17% slip. Way too high. If I had to guess, you are trimming the motor right up to get more rpm giving you massive slip and making it unstable at speed. Your holeshot must be brutal.

If you really have a 1.62 gear case you should be running a 23p prop at most. Trophy is a good bet for these hulls. 2.5"-3" below the V and you should be good for 75 MPH.

I have a 250 Etec and run a 25p Rev4. Good for 74 mph. I would think the 250xs should be faster.

Yes Mark you are wright thats what I said before Nick you have to start with a low pitch prop with that gear ratio and work your wat up and make sure you keep the rpm up (6000 - 6300)

denis leblanc
05-15-2012, 10:25 PM
Back in the day there were some with 300 V-8 OMC's that ran upwards of 80 and from what I read on here they are pretty stable at those speeds for a boat that was probably never intended to run that fast. Unfortunately it isn't the most efficient hull for high speed running but it does do very well in some pretty heavy chop for a relatively small boat.

If the set up is right then the driver doesn't have to be crazy. ;)

John

I know they ran realy good with the V-8 because the motor is heavy and it was easier to get the bow up with the proper prop and engine thorque is a lot more so you were able to run a prop with more cup

denis leblanc
05-15-2012, 10:43 PM
Nick there is a big diff. in prop the one you have the 27p is made to run on a boat with a pad (hydrostream) so running that 25p will be a good start. You said that you know someone with same boat,set-back,prop,motor and he does 80-85mph does is steering hard also can he turn right and left to drive through a chine? is he running same gear ratio? You see the more you trim to get the prop to spin at 5300 the boat runs like a snake because you are running out of bite on the prop you must have a high rooster tail ? and that tells you that you are trim too much at top speed the tail should be the height of the motor

gees too bad I am not close to you I would love to set it up with you:brickwall:

nickhedstrom
05-16-2012, 12:21 AM
Yeah its a pretty neat sight behind the boat, but if i trim the motor down so the rooster tail is bout the height of the motor i lose speed cause more boat is in the water. I found a 24p 4B Trophy Plus in wisconsin for 450.00 new. I should get it but i wish it was a 25p but if i dont like it i guess i could resell it. I think thats gonna be my next step so i can see how the boat reacts and then ill let u know. BTW where in Ontario are you, i go to Chapleau several time a year. (its straight north of the Sault St. Marie)

nickhedstrom
05-16-2012, 01:01 AM
I have my choice of a 24p or 25p 4b trophy plus new. With what ive said what one should i start with?

Needafunboat
05-16-2012, 02:04 AM
Would like to try a 25p or 26p 4B Trophy if i could get my hands on one.

I have a nice 26p trophy I'm looking to sell. It's not the plus - so you can't use standard vent hole plugs but it also has thinner blades than the plus and is supposed to be a little faster. Nice prop - worked well on the starliner with a light load but the 24 p was better all around with my 225.

Hey that's another thing - my boat never ran well with a 3 or even 5 blade prop. Trophys were the only thing it liked. A rev 4 might be good too.

Anyhow PM me if you're interested - I live near brighton.

Rob B
05-16-2012, 07:38 AM
Back in the day there were some with 300 V-8 OMC's that ran upwards of 80 and from what I read on here they are pretty stable at those speeds for a boat that was probably never intended to run that fast. Unfortunately it isn't the most efficient hull for high speed running but it does do very well in some pretty heavy chop for a relatively small boat.

If the set up is right then the driver doesn't have to be crazy. ;)

John

That's Robz boat Starflite you're talking about. http://checkmate-boats.com/forums/showthread.php?t=11429

http://checkmate-boats.com/forums/showthread.php?t=12370

atc250r
05-16-2012, 09:13 AM
Nick,

If you're going to buy new I would suggest checking out blades site. Their prices are competitive and their prop trying program can't be beat.

John

Mark
05-16-2012, 02:04 PM
I have my choice of a 24p or 25p 4b trophy plus new. With what ive said what one should i start with?

I think you are crazy to buy a new prop before you have figured out where you should be pitched. I would try any prop I could get my hands on to get closer to my optimal RPM and then go from there.

Stiffer prop does not mean faster boat. The right prop means faster boat.

A 25p Trophy could make 5600-5700 RPM, a 24p 5750 - 5800, a 23p 5900-5950. Best guesses. If you have a 1.62 LU (I would verify that fact) then the 23 would be my choice.

I always prop my boats for max RPM. Better holeshot, better handling, better load carrying... usually just as fast.

atc250r
05-16-2012, 02:07 PM
Just wanted to fix the typo in my last post to avoid confusion, the site is www.bblades.com.

BagMan
05-16-2012, 03:50 PM
I think you are crazy to buy a new prop before you have figured out where you should be pitched. I would try any prop I could get my hands on to get closer to my optimal RPM and then go from there.

Stiffer prop does not mean faster boat. The right prop means faster boat.

A 25p Trophy could make 5600-5700 RPM, a 24p 5750 - 5800, a 23p 5900-5950. Best guesses. If you have a 1.62 LU (I would verify that fact) then the 23 would be my choice.

I always prop my boats for max RPM. Better holeshot, better handling, better load carrying... usually just as fast.

Absolutely right. Not to mention avoiding detonation/meltdown.

denis leblanc
05-16-2012, 08:47 PM
I have my choice of a 24p or 25p 4b trophy plus new. With what ive said what one should i start with?

I would start with the 24p its up to you and you can always sell it. the person you are buying the prop from would he be willing to let you try it? I am running a 25p 3b Tempest Plus that I had to get modified to be able to run 6100rpm to get 88mph

denis leblanc
05-16-2012, 08:52 PM
Yeah its a pretty neat sight behind the boat, but if i trim the motor down so the rooster tail is bout the height of the motor i lose speed cause more boat is in the water. I found a 24p 4B Trophy Plus in wisconsin for 450.00 new. I should get it but i wish it was a 25p but if i dont like it i guess i could resell it. I think thats gonna be my next step so i can see how the boat reacts and then ill let u know. BTW where in Ontario are you, i go to Chapleau several time a year. (its straight north of the Sault St. Marie)

Nick Chapleau is still 10 hrs. away from me

denis leblanc
05-16-2012, 08:59 PM
I think you are crazy to buy a new prop before you have figured out where you should be pitched. I would try any prop I could get my hands on to get closer to my optimal RPM and then go from there.

Stiffer prop does not mean faster boat. The right prop means faster boat.

A 25p Trophy could make 5600-5700 RPM, a 24p 5750 - 5800, a 23p 5900-5950. Best guesses. If you have a 1.62 LU (I would verify that fact) then the 23 would be my choice.

I always prop my boats for max RPM. Better holeshot, better handling, better load carrying... usually just as fast.

Same here!!! Mark you are so wright:cheers:

denis leblanc
05-16-2012, 09:16 PM
Nick !! this may sound stupid but your boat may have a hook in the "v" area it happen to me before on on of my J-Craft. if your boat is stored on the trailer that does not support it properly for a good period of time in the cold or in the heat fiberglass has a tendency to shift a bit to check that is put the boat on the trailer and from the back of transom put a 6ft. straight edge at the "v"and there should not be a gap check it also on each side of all the stringer v up to the edge of the boat. If the boat has a hook the bow will never lift and chine walk like crazy

Mark
05-17-2012, 11:05 AM
It is easy to get frustrated trying to turn the Starflite/Starliner into something it was never meant to be... a rocketship. These boats have a stepped hull and a V shaped pad instead of flat. A step will, and is designed to, draw the bow down at speed. Typically this design works best for bigger go-fasts that will never 'fly' on pad. You can feel it happen on a Starflite at around 40 MPH. In our attempt to go faster we add more power and more setback and try to lift the step out of the water. You can also feel (and hear - aerating stops) that happen somewhere over 60 MPH. The 300 hp V8 Johnson back in the 80's did a good job of this because of the shear weight and horsepower of the beast. But we are really fighting against the way the hull was designed. Nose cones and super high engine heights are all counter productive.

In the 1990's Checkmate redesigned the hull with a flat pad and no step, which of course is the Pulsare. They must have realized the Starflite was too small to need a stepped hull. It rides very differently and horsepower for horsepower a Starflite will never keep up with a Pulsare. On the other hand they will arguably do better in the slop.

My feeling is that we should set these boats up to make the best of their design features. A heavy motor, moderate setback, and a 4 blade prop will lift the bow enough to avoid resistance from the step and ride high... but never really fly on pad. Depending on the horsepower it should be good for 65-80 MPH. Play with the setup, get the max out of it and ENJOY. To compare speeds to a Pulsare will do nothing but leave you frustrated.

atc250r
05-17-2012, 11:12 AM
I know one of the guys here added a pad to his, I'd love to know how it ended up working out and if it picked up significant speed.

Mark
05-17-2012, 11:33 AM
He hasn't been around since the fall. He never did give speed numbers with the pad but said it ran smoother. http://checkmate-boats.com/forums/showthread.php?t=21274

denis leblanc
05-17-2012, 10:20 PM
Mark you are so right again !! you know your stuff , and I mention in a post before back in the days we put v8 300hp Jonhson with lots of set back and ran fine because of the weight and thorque of those engines and was able to get the bow up. These starflite were never made to to be the fastess boat on the lake they look mean and ran 75mph we were all happy> I am going to do some home work and find out the weight of those v8 engines and compare it to the new 300XS Optimax and 250XS Optimax and compare the thorque difference and I will come back with the fax result

nickhedstrom
05-18-2012, 08:51 PM
Ok guys get this, tried 25P 4B Trophy Plus stock prop today and got the same speed and the same RPMs as my other prop (70mph at 5300-5400). The other prop was a Hydromotive 27P 4B worked and labbed. The chime walk improved very little. Noticed less chime the higher the motor (1 1/2 to 2" below the vee. One thing i noticed is that the hub on the Trophy is smaller than the lower unit so it doesnt look streamed line from lower unit to prop, (where the to meet). Could this cause a problem? Plus the higher the rooster tail the faster the boat went. I wonder if i got a problem with the motor not able to get rpms out of it. The motor only has bout 35hrs on it but i suppose a plug could have fouled out. It has some vibration at bout 1200rpms and sounds a little funny idleing. Could these motors still push a boat on plane and to 70mph on 5 cylinders? (08 250xs)

nickhedstrom
05-18-2012, 08:53 PM
BTW the new prop was run for 1 hour and the inside of the new prop was very black inside when we pulled it out of the water. Or is this normal?

denis leblanc
05-18-2012, 09:22 PM
BTW the new prop was run for 1 hour and the inside of the new prop was very black inside when we pulled it out of the water. Or is this normal?

Nick Yes this could be normal because at this time of the year the water is colder than the summer and the computer sends more fuel and the motor could run rich (black hub & black plugs) and the type of oil is important for the injection system but if you have this black soup in the hub in the summer time you have to take it to the dealer to callibrate the computer sometime these engines are set on the rich side because of the waranty. Do a speed run next time and when at full throttle shut it of in gear do not bring to neutral cause it will not have same reading keep the control at full and when you come to a stop pull all the plugs out and they should be light brown if they are not take it to the dealer because a engine that runs rich all the time is not good for the piston rings the grooves will get soupy and the rings can start sticking and you lose compression and power

Mark
05-18-2012, 09:40 PM
The hub is probably black because you are lugging the motor. The computer tells it to increase the oil. You still have too much prop for 1.62 gears. And no you would not get to 70 mph on 5 cylinders.

The Trophy is a small hub prop and is meant to fit like that. It allows some of the exhaust to vent over the hub during holeshot to get you going quicker. At speed the water covers the gap and it has no effect after that.

Because you are still over-propped you are having to trim the crap out of it to get your rpm up. But you now are seeing 9% slip which is good. You just need to get the right pitch prop. I would still try (not buy) a 23p Trophy. You might need even less from what you are seeing with the 25. If you can get a 23 to spin 6000 rpm at 9% slip you would get 74 mph.

For a frame of reference my 250 Etec has a 1.85 gear ratio and I can turn 26 Trophy to 6000 RPM for 73 MPH. Do the math as to what prop you need with the 1.62 gears before you waste any more money.
http://www.go-fast.com/Prop_Slip_Calculator.htm

denis leblanc
05-18-2012, 09:45 PM
Ok guys get this, tried 25P 4B Trophy Plus stock prop today and got the same speed and the same RPMs as my other prop (70mph at 5300-5400). The other prop was a Hydromotive 27P 4B worked and labbed. The chime walk improved very little. Noticed less chime the higher the motor (1 1/2 to 2" below the vee. One thing i noticed is that the hub on the Trophy is smaller than the lower unit so it doesnt look streamed line from lower unit to prop, (where the to meet). Could this cause a problem? Plus the higher the rooster tail the faster the boat went. I wonder if i got a problem with the motor not able to get rpms out of it. The motor only has bout 35hrs on it but i suppose a plug could have fouled out. It has some vibration at bout 1200rpms and sounds a little funny idleing. Could these motors still push a boat on plane and to 70mph on 5 cylinders? (08 250xs)

Yes it will get it on plane and 70mph but this is probably why you are only getting 5300rpm with the new prop. for the prop not lining up with lower unit yes it is choking the motor a bit for you to run that prop you will have to get it to a prop shop and get them to drill vent holes in the prop and there is a proper place to drill to keep the prop balanced. And yes you could of fouled a plug that is normal it can happen any time especially when the water is very cold and your engine runs rich

denis leblanc
05-18-2012, 10:07 PM
Ok this is how a prop works ex. a 25p prop does 25in. for each rotation, a 27p will do 27in./rotation so rule of thumb if you can run a 27p @6000rpm you will get more mph 2 reasons : 1 the prop travels more and : 2 the more it travels it lifts the bow more and you do not have to trim as much and more bite more speed. So you ran the new prop today and got the same rpm & mph this is normal cause the prop is smaller and puts less load on engine and you were able to trim up a bit more and got the bow up a bit and got same mph. Just imagine if you can get that 27p prop to run @ 6000rpm you will be in the mid 80mph but the chances are slim with that prop and your boat so again like I say start with a low prop toget rpms and you will be surprise you may get more bow lift and mph and keep the rpm up

I love boating so much that I could talk all night

Nick do not quit try every thing this is how you acquire your experiance and you share with freinds

denis leblanc
05-18-2012, 10:14 PM
The hub is probably black because you are lugging the motor. The computer tells it to increase the oil. You still have too much prop for 1.62 gears. And no you would not get to 70 mph on 5 cylinders.

The Trophy is a small hub prop and is meant to fit like that. It allows some of the exhaust to vent over the hub during holeshot to get you going quicker. At speed the water covers the gap and it has no effect after that.

Because you are still over-propped you are having to trim the crap out of it to get your rpm up. But you now are seeing 9% slip which is good. You just need to get the right pitch prop. I would still try (not buy) a 23p Trophy. You might need even less from what you are seeing with the 25. If you can get a 23 to spin 6000 rpm at 9% slip you would get 74 mph.

For a frame of reference my 250 Etec has a 1.85 gear ratio and I can turn 26 Trophy to 6000 RPM for 73 MPH. Do the math as to what prop you need with the 1.62 gears before you waste any more money.
http://www.go-fast.com/Prop_Slip_Calculator.htm

Mark you are wright again I second the motion:cheers:

nickhedstrom
05-18-2012, 11:45 PM
This doesnt make sense though, i go from a 27P to a 25P which should be at least 500rpm, and the 27P is a 15" diameter and the 25P is a 13 3/4" diameter so i should gain rpms there too but i stayed the same (5300). This motor with 1.62 LU and 25P 4 blade should be all day 5800rpm no questions asked.

nickhedstrom
05-18-2012, 11:55 PM
Or more, Y dont they post or stamp on the outside of the motor what the ratio is like they did on I/O. 1.5, 1.62, 1.75 ect. From other boats simalar im missing 10mph plain and simple. All my speeds are true GPS handheld. BTW the air temp was 85 today and water temp was 60 but i know they got stats in them and if they read water temp they would run rich all the time. Dont they have a sensor in them to tell the computer thats its too rich or too lean like a O2 sensor on a car?

nickhedstrom
05-19-2012, 12:01 AM
Before i got this 250xs i had a 95 200xri efi with 6" less set back and a wrong prop on it and i still got 65mph GPS all day long. Didnt matter to much on engine height and trimmed it pretty good. This is crazy!!!!!

Mark
05-19-2012, 12:57 AM
If you have 1.62 gears your LU should have a nose cone and be silver. Although I am not an expert on Mercs.
Yes it is strange that the 25 and 27 are both turning the same revs. Not sure you are missing 10 mph though. Don't forget most everybody lies.

I had a 200xri on mine as well and saw about the same... 65ish. I figured I would get a lot more with the 250. But 74 is it so far. Kalugs22 is seeing 76 with the same motor as you.

Sometimes propping a new motor can be a pain. It is possible your motor is not running right, but I think you would be able to tell by how it sounds coming up to speed. Like I said before I would try every prop I could beg, borrow or steal until you figure out what your combo likes.

nickhedstrom
05-19-2012, 01:37 AM
Yes its silver and got a nose cone with low water pick up built in. Its got a massive skeg that looks like it would drag u down a ton. Dont need this LU cause this boat doesnt want a hi running motor.

Mark
05-19-2012, 01:10 PM
Yes its silver and got a nose cone with low water pick up built in. Its got a massive skeg that looks like it would drag u down a ton. Dont need this LU cause this boat doesnt want a hi running motor.

The Sportmaster LU is probably working against you. When you trim out a Sporty the nosecone actually creates drag. They are meant to be elevated until you no longer need much if any trim at all. It works great on lighter boats and will even work on a Pulsare, but it is not likely the right fit for a Starflite. You should be able to trade someone for 1.75 Torquemaster which should work well with your 25p Trophy. But you may want to check this out with someone more acquainted with these motors and LU's than me. SCT would know. Wildman or kct11.

nickhedstrom
05-19-2012, 06:16 PM
Thats what Todd said at Hydromotive, he wants to test trial and switch out my sporty for a torque master, he has a good friend that will let him. I also pulled the plugs on the motor and all 5 look good and the same but 1 has a bunch of carbon deposits on the arch part of the plug and is alot blacker. Another thing i saw is the plugs in it now are IZFR6J NGK and the sticker on the motor says IZFR6G NGK, which is the correct plug? Let me know. Thanks everyone for the help.

nickhedstrom
05-20-2012, 09:01 AM
Also do these plugs need to be indexed when installed?

denis leblanc
05-22-2012, 09:49 PM
Nick!! keep us posted on your next move and how you are making out

don't quit

Dan_az80
01-28-2013, 05:34 PM
The steering is so hard at WOT that its slips, i mean the steering wheel will turn but the motor doesnt.


Do you have the same problem with the 200 XRi on the back? Just a general question to all, what would cause the steering issue with a hydraulic set-up?

fox88gt
02-06-2013, 03:37 PM
I wish you the best of luck with your Starflite, I have one myself and they are wonderful, beautiful rigs, even when set up more modest (mine just has a 2.4 200 blackmax merc). I must say, I believe the SportMaster is making your life difficult at this time, as well as the 1.62 ratio. A TorqueMaster with the 1.75 (please correct me if I'm wrong) ratio will be better suited for the boat. Sporty's are meant for surface piercing applications, which a Starflite really isnt. The TorqueMaster will still have the low water pickups that you'll need. The pointy nose cone on a Sporty is meant to ride 1/2 out of the water. When fully submerged, the rounded nose of the TorqueMaster is actually more efficient. The nosecone on the Sporty is probably inducing much of the chine walk because it is fully submerged.

There's a ton of great advice on this site and I'm sure you'll figure it out in the end.....Plus, if you switch to a TM you can sell your sporty and possibly come out ahead:popcorn:

Jeff