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Premium Member
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Discussion Starter · #1 ·
I'm looking to get the most out of my 600sci and I don't believe the current prop is doing it. I am running a 15 1/4 x 28p, but my peak rpm is around 4,900 to 5,000. I was wondering what size prop other people are running with this motor and the type of performance numbers you are seeing. My boat is a DCB 28 Extreme....I hit 78mph on GPS, but I think she might have a little more left in her....

Thanks,
B
 

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Still Boatless :-(
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I'm looking to get the most out of my 600sci and I don't believe the current prop is doing it. I am running a 15 1/4 x 28p, but my peak rpm is around 4,900 to 5,000. I was wondering what size prop other people are running with this motor and the type of performance numbers you are seeing. My boat is a DCB 28 Extreme....I hit 78mph on GPS, but I think she might have a little more left in her....

Thanks,
B

What is the red line on your engine? I seems to me the prop is about right. If you want more RPMs you would have to go to a lower pitched prop and your top speed would go down (and you might over-rev the engine).

If you go to a higher pitched prop, your RPMs would go down, you would be putting a greater load on the engine (especially at take off) and you probably wouldn't get any more speed.

:)bulb
 
G

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I'm looking to get the most out of my 600sci and I don't believe the current prop is doing it. I am running a 15 1/4 x 28p, but my peak rpm is around 4,900 to 5,000. I was wondering what size prop other people are running with this motor and the type of performance numbers you are seeing. My boat is a DCB 28 Extreme....I hit 78mph on GPS, but I think she might have a little more left in her....

Thanks,
B
Seems like a 600sci spinning a 28 at 4900 to 5000 is on the light side. You might want to have a good prop person check out the pitch and cup on your prop. I'm able to spin a Merc labbed 28 4900 with an HO with headers.
 

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Floatin dirty
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I'm looking to get the most out of my 600sci and I don't believe the current prop is doing it. I am running a 15 1/4 x 28p, but my peak rpm is around 4,900 to 5,000. I was wondering what size prop other people are running with this motor and the type of performance numbers you are seeing. My boat is a DCB 28 Extreme....I hit 78mph on GPS, but I think she might have a little more left in her....

Thanks,
B

You might want to look at a Hydromotive P5X. It is a very good bow lifting prop and I used it on my 29 Lavey V bottom after Teague took it out for water/prop testing for me. It provided far better mid range speed at various RPM's and my top end increased as well.
 

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The Insurance Guy
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I think you have the right prop. Having it labbed would be a good idea though. My boat is about the same size as yours, I am running around the same power with a 28p and my best day so far was 78gps. I can tell you that a 30p would be too big for my boat, so i would imagine yours will be the same.
 

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I have a 600 sci. I sent the ecm to Whipple for a stage one reflash.

After the reflash and with a 28 pitch 5 blade Maximus at 5800 rpm I have run 90. The fastest I have been in the boat was 93 mph. Typically the boat runs around 88 mph loaded and depending on temperature and load. With the 4 blade Bravo one props I get a slower speed by 2-3 mph and a slower cruise speed. I think there is alot more in the motor. Have Dustin do a stage one or stage 2 for you and wake that thing up.
Stage 1 670 hp
Stage 2 I am not sure what hp but I think 750 hp

The 600 motor is identical to the 700 except the cam and pulley.

I would prop test and get those rpms up in to the 5400 range.

Good luck
 

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Ultra 27 Shadow
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I have a 600 sci. I sent the ecm to Whipple for a stage one reflash.

After the reflash and with a 28 pitch 5 blade Maximus at 5800 rpm I have run 90. The fastest I have been in the boat was 93 mph. Typically the boat runs around 88 mph loaded and depending on temperature and load. With the 4 blade Bravo one props I get a slower speed by 2-3 mph and a slower cruise speed. I think there is alot more in the motor. Have Dustin do a stage one or stage 2 for you and wake that thing up.
Stage 1 670 hp
Stage 2 I am not sure what hp but I think 750 hp

The 600 motor is identical to the 700 except the cam and pulley.
I would prop test and get those rpms up in to the 5400 range.

Good luck
I would look into some five blades and labbing. Take the prop over to Bronson Hill and have them look at it as well.

The 700 has a larger intercooler than the 600 if I am not mistaken.
 

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Floatin dirty
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I have a 600 sci. I sent the ecm to Whipple for a stage one reflash.

After the reflash and with a 28 pitch 5 blade Maximus at 5800 rpm I have run 90. The fastest I have been in the boat was 93 mph. Typically the boat runs around 88 mph loaded and depending on temperature and load. With the 4 blade Bravo one props I get a slower speed by 2-3 mph and a slower cruise speed. I think there is alot more in the motor. Have Dustin do a stage one or stage 2 for you and wake that thing up.
Stage 1 670 hp
Stage 2 I am not sure what hp but I think 750 hp

The 600 motor is identical to the 700 except the cam and pulley.

I would prop test and get those rpms up in to the 5400 range.

Good luck

Did you leave the diffuser ring on the maximus or have it cut off?
 

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Shipping guy... you are right on the intercooler, sorry.

I have had better luck with the five blade. Boat is a Howard Deck. I don't know if this would be better for a vee or not. I would definately try one.
 

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Did you leave the diffuser ring on the maximus or have it cut off?

I have one with and one without. My favorite is the one with it on. They are supposed to be faster without them and you can get more bow lift which is important with a modified tunnel. With a vee you everything could be different.
 

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There is a guy on the board with a Nordic Heat and a stage 2 and he is running 93-94 mph. Check him out. He posts mainly on offshore only but he is on this board also. He has alot of prop testing info and I believe his favorite is a hydromotive p5x
 

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There is a guy on the board with a Nordic Heat and a stage 2 and he is running 93-94 mph. Check him out. He posts mainly on offshore only but he is on this board also. He has alot of prop testing info and I believe his favorite is a hydromotive p5x
His name is Chris and he's definately done his homework.

Based on your slip numbers, your right in the 7-8% range which is too low for that boat. Single V's like to run the 11-12% range.

So the first thing he's going to tell you is that in order to run the 5 you'll need to come up with your drive. The 5's dont work as well with a deep prop shaft. His current set-up has the prop shaft approx. 3" below the keel of the boat and I'm guessing your going to be roughly 4.5". The 5 likes to be closer to the top in order to "free up". I personally have run mine as high as 2.5" below the keel and have no probelm hooking up it's just that my slip starts to push up and my speed falls (710 Ilmor in a 28 Nordic Heat)

If you put on a labbed 28 B1, you could see about 400 R's by loosing the extra blade and the labbing, which is right about where you want to be with that motor (which might get you a couple MPH's). Beyond that, it's all about set-up for your boat and hp to weight.
 

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Give Kevin a call at R&R Prop Shop in Vegas. ;)

www.randrpropshop.com

(702) 564-7502
I'll second this recommendation. What make prop do you have on there now? 15 1/4 x 28 5-blade, is that a Hydromotive prop? Maximus is 15 1/2, so probably not that.

Had Kevin run your numbers right quick and guessing at 5000# in the water, with 600hp, and he comes up with (funny enough) 78mph. Sounds like you're propped pretty well already.

That motor is designed for 4800-5200 max rev range according to Merc, so aything you do will likely trade RPM for slip. Going to a 30p 4-blade Bravo 1 for instance...more slip, more RPM, but the speed would likely stay about the same. Bravos are real common though...I'm sure you could find one to try.
 

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Discussion Starter · #18 ·
I'll second this recommendation. What make prop do you have on there now? 15 1/4 x 28 5-blade, is that a Hydromotive prop? Maximus is 15 1/2, so probably not that.

Had Kevin run your numbers right quick and guessing at 5000# in the water, with 600hp, and he comes up with (funny enough) 78mph. Sounds like you're propped pretty well already.

That motor is designed for 4800-5200 max rev range according to Merc, so aything you do will likely trade RPM for slip. Going to a 30p 4-blade Bravo 1 for instance...more slip, more RPM, but the speed would likely stay about the same. Bravos are real common though...I'm sure you could find one to try.
Sorry, it's a 15 1/2 x 28P Maximus...5 blade
 

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Those 5 blades bit hard BE CAREFUL....
I would try a labbed 30 4 blade and remember IT IS COOLING OFF... So that prop you have is a great summer prop, WITH ALOT OF BITE
 

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I'm looking to get the most out of my 600sci and I don't believe the current prop is doing it. I am running a 15 1/4 x 28p, but my peak rpm is around 4,900 to 5,000. I was wondering what size prop other people are running with this motor and the type of performance numbers you are seeing. My boat is a DCB 28 Extreme....I hit 78mph on GPS, but I think she might have a little more left in her....

Thanks,
B
I assume you are running a stock 28 Bravo and have a 1.5:1 Mercury Midwater XR drive? When you are running 49-5000 is that with a usual load/outside temperature? Do you feel the boat slipping throughout your midrange and how does it trim @ top speed? Either way, for a bit more RPM (w/ out losing speed) a labbed prop is your answer.

If you notice the prop slipping alot you might want to try a 15 1/4" x 27-28 Labbed Maximus w/ 5/8" cut off the diffuser. This prop will really help you get the boat onto plane and help carry the nose (lots of lift) w/ out having to trim it to the moon!

If the Bravo feels pretty good on the bottom end and mid range is good, a Mercury Labbed Bravo will work out great. It will slip a bit more, but you have your supercharger to compensate for this (don't break your drive though).. I would guess a 15 1/4" x 29 Lab Bravo 1 will be your magic number. You will pick up approx 150-200 RPM depending how much more it slips? It takes RPM to make speed.

I feel we can get 80 out of your package the way it is or.... Like these guys said, Whipple makes a few different upgrade kits for your engine that are very safe and effective! You can convert to a 700HP kit for approx. $2,200... If you are thinking of Whipple upgrades, a IMCO lower case might also be a performance thought!

Give me a call if you like and we can talk more and allow me to get more familiarized w/ your boat! Best of luck to you! -Eric

TEAGUE CUSTOM MARINE
661.295.7000
www.teaguecustommarine.com
 
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