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I'm baaaaack...
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We have decided to keep the Cheetah. We took it out the past couple of days and had a blast running in a smaller boat, especially one that's paid for. The boat is nice and solid, has a 6.2/377 SBC Merc engine with a through transom exhaust. I'd like to replace the cast risers and manifolds with headers like my 600 SCi has, and I've seen on 525s. They won't need to be polished, but the weight loss, fewer gaskets (it always seems to spring a leak between the manifold and riser), and increase in power are all factors in my thinking here.

Does such a thing exist? Do they work for what I'm looking at? Is this question more for Teague or Rex?
 

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We have decided to keep the Cheetah. We took it out the past couple of days and had a blast running in a smaller boat, especially one that's paid for. The boat is nice and solid, has a 6.2/377 SBC Merc engine with a through transom exhaust. I'd like to replace the cast risers and manifolds with headers like my 600 SCi has, and I've seen on 525s. They won't need to be polished, but the weight loss, fewer gaskets (it always seems to spring a leak between the manifold and riser), and increase in power are all factors in my thinking here.

Does such a thing exist? Do they work for what I'm looking at? Is this question more for Teague or Rex?

You guys are rite! CMI is by far the best option for your SBC! They have the best look, best HP/torque gains, and are S.S. so they will hold up to our Colorado river water (we all know how that is on our boats)! The cool thing anout a SBC is that it is lighter than a Big Block, so when we add some power you will see and increase! CMI tested @ up to 40HP+ and 10% torque increases so exoect about a 300RPM increase! Most likely you will need a bigger prop (a very good thing)!

http://teaguecustommarine.com//store/index.php?main_page=index&cPath=198_828_486_490

SBC E-Tops Satin- $2199.97+ Tails ($3030.58 CMI retail)
SBC E-Tops Full Polish- $2499.97+ Tails ($3457.54 CMI retail)

Give me a call and i would be happy to provide more info and get you a quote for tails! -Eric


TEAGUE CUSTOM MARINE
661.295.7000
www.teaguecustommarine.com
 

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You guys are rite! CMI is by far the best option for your SBC! They have the best look, best HP/torque gains, and are S.S. so they will hold up to our Colorado river water (we all know how that is on our boats)! The cool thing anout a SBC is that it is lighter than a Big Block, so when we add some power you will see and increase! CMI tested @ up to 40HP+ and 10% torque increases so exoect about a 300RPM increase! Most likely you will need a bigger prop (a very good thing)!

http://teaguecustommarine.com//store/index.php?main_page=index&cPath=198_828_486_490

SBC E-Tops Satin- $2199.97+ Tails ($3030.58 CMI retail)
SBC E-Tops Full Polish- $2499.97+ Tails ($3457.54 CMI retail)

Give me a call and i would be happy to provide more info and get you a quote for tails! -Eric


TEAGUE CUSTOM MARINE
661.295.7000
www.teaguecustommarine.com
What are the intallation costs on something like this? It seems like a no-brainer but if you not installing yourself, I would imagine the total cost is pretty steep.

I'm not even sure how fast my boat goes, but we are always skiing, wakeboarding or carrying a load of people so I'm sure it would make a big difference.
 

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I'm baaaaack...
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Discussion Starter · #7 ·
You guys are rite! CMI is by far the best option for your SBC! They have the best look, best HP/torque gains, and are S.S. so they will hold up to our Colorado river water (we all know how that is on our boats)! The cool thing anout a SBC is that it is lighter than a Big Block, so when we add some power you will see and increase! CMI tested @ up to 40HP+ and 10% torque increases so exoect about a 300RPM increase! Most likely you will need a bigger prop (a very good thing)!

http://teaguecustommarine.com//store/index.php?main_page=index&cPath=198_828_486_490

SBC E-Tops Satin- $2199.97+ Tails ($3030.58 CMI retail)
SBC E-Tops Full Polish- $2499.97+ Tails ($3457.54 CMI retail)

Give me a call and i would be happy to provide more info and get you a quote for tails! -Eric


TEAGUE CUSTOM MARINE
661.295.7000
www.teaguecustommarine.com
Does the computer require reflashing, similar to the rejetting needed on a carb engine when you add headers?
 

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C M I - Bmall Block!

What are the intallation costs on something like this? It seems like a no-brainer but if you not installing yourself, I would imagine the total cost is pretty steep.

I'm not even sure how fast my boat goes, but we are always skiing, wakeboarding or carrying a load of people so I'm sure it would make a big difference.
Hey RodnJen,

Installation on your boat is going to be pretty easy, since it is a single engine v-bottom! I would predict it would be about 4-5 hour to remove the old and install the new and have it ready to go. I say if you are half way mechanicly enclined, you could install these in a day..

You will pick up top speeds, but your bottom end and midrange is really going to improve. Your Engine being able to breathe easier, will accelorate better from the bottom end (pulling a skier onto plane w/ too many people on the boat) and your mid range will increase the same way (pull away from your friend who thinks he is hot s#%t).

Remember, you will need tail pipes for these bad boys, so i attached the links for you to print and fill out.

Shop Build Sheet-
http://www.custommarine.com/pdf_docs/CMI_form01_ShopBuildInfoSheet.pdf
Transom Layout-
http://www.custommarine.com/pdf_docs/CMI_form02_SingleEngineTransom.pdf

If you guys have any questions, feel free to give me a call! -Eric

TEAGUE CUSTOM MARINE
661.295.7000
www.teaguecustommarine.com

 

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Does the computer require reflashing, similar to the rejetting needed on a carb engine when you add headers?

hkunz,

Good Question! This system does not require any re-programming of your computer (EFI) or carb. adjustments.. Just bolt them on and go! IF you decide to go farther into your engine w/ upgrades you will have to work your computer/new carb. @ that point, but your CMI exhaust will be there for you forever! -Eric

TEAGUE CUSTOM MARINE
661.295.7000
www.teaguecustommarine.com
 

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I would think we'd all benefit from a re-flash to free up these small blocks either way.
Just think of it as adding a chip to your car or truck...right???

The guys at Oregon Custom Marine re-flashed a 350 mag SBC with Lighting headers and picked something like 6 - 8 MPH on a 22' Nordic, they got 68-70 MPH
The way I've always read was 10HP per MPH so we're talking a good HP bump here right?
Correct me if I'm wrong
 

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i cant believe how much SBC headers cost for boats ! i was just thinking about up grading my headers from my volvo manifolds, but now i think im happy where im at lol. i paid 2800 for my entire boat on the trailer. i dont think i could swallow that same amount for just headers
 

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jeffz0rz- This is why it is often cheaper to build a performance big block than a small block.
with a BBC there is Availability of good used performance parts- like exhaust.

Problem with cheaping out here is that this one mod- exhaust, is the foundation that all other performance mods will "stand on" in the future.

There are good parts from both coasts.

Cut a deal with your manufactuerer directly, or a local builder to put them in.

Uncle Dave
 

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this is all new to me. definitely about as green as they come when it comes to the performance side of boating. guess ill start saving my bottles and cans for my big block swap in the future.
 

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this is all new to me. definitely about as green as they come when it comes to the performance side of boating. guess ill start saving my bottles and cans for my big block swap in the future.
Welcome to the "circle jerk" of speed.

When your boat reaches 80 MPH- put aside another 5/10 K for a "real" hydraulic steering system.- or you boat just goes straight no matter what you do with the wheel.

by the time youve put some higher HP hours you'll need to rebuild the drive and thats like another 5K ......

and... you get the ideal.

However- boast are one of the last frontiers of speed that isnt ridiculously overrated.


Welcome to my world....

Uncle Dave
 

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I just bought an Ultra with a 6.0 Vortec and it has a set of IMCO "Thumper" manifolds on it. They sound pretty good, not too loud, and give the little engine pretty good throttle response. Surely not as much of a gain as the CMI's, but I think these run just over a grand for a set.

Something to think about at least...
 

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Welcome to the "circle jerk" of speed.

When your boat reaches 80 MPH- put aside another 5/10 K for a "real" hydraulic steering system.- or you boat just goes straight no matter what you do with the wheel.

by the time youve put some higher HP hours you'll need to rebuild the drive and thats like another 5K ......

and... you get the ideal.

However- boast are one of the last frontiers of speed that isnt ridiculously overrated.


Welcome to my world....

Uncle Dave
Where else can you build up a BBC and run it WFO for more than a few seconds without breaking any laws!
 
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