No chance, or unreasonable, to buy exhaust from Banks ?

I totally struck out with them. If someone had a connection it might happen, same for marine diesel in Texas, they want to sell their motors, not help someone else build one.
They are not really that hard to build but like most of this one off stuff, your done by the time you figure out how to streamline the job.

I think Kid had someone in Calif who would cast them but he needed volume.

I recently committed to ordering 2 of those Banks marine intakes with the Cupronickel heat exchanges at $4500 each, and they told me NO on the exhaust manifolds. I don't believe they actually have anything made up to sell. Same answer from the TX boys, not interested in selling any custom pieces alone.

In a couple pics and videos from Banks, you can see he's using Nicson jet boat manifolds on the Duramax setup. Closer looks shows an adapter plate between the head and manifold. So I did a little asking around, seems 392 HEMI shares similar port shape and dimensions. If that's correct, you can pick up those Nicson cast aluminum manifolds used off eBay for a couple hundred and likely be running for well under a grand. For fresh water use only of course..

[ATTACH=CONFIG]555758[/ATTACH]

As Hoodoo mentioned I've worked with another Dmax boat owner on casting some manifolds in aluminum or stainless steel. We could 3D print the molds, then cast them as needed. But that first set was quoted at about 10k, so need to sell more than a couple.

That leaves us with custom SS headers or log style manifolds as the reasonable choice. After checking out pricing from CMI, and returning the set built by a small independent shop, my friend in Cali ask me to build a set. So I followed the approach Hoodoo took with the simple log design header.

[ATTACH=CONFIG]555763[/ATTACH]

More on these next.

Interesting.

I was referring to these from Banks.
Pics: http://banksmarine.com/

And on video:
https://www.youtube.com/watch?v=M32tIPCchTA

Yeah those are what I ask about. Same intakes I ordered also. Think I got the last pair of them if it tells ya anything..

Since choices for good water cooled 6.6L Duramax manifolds or headers can be counted on one hand with several missing fingers, I've attempted to find a good SS tig welder to take on this task. First I contacted the marine exhaust pro's, where prices came in between 6-9k per set. Next checked with a couple big welding shops that specialized in stainless, they all passed.

[ATTACH=CONFIG]555773[/ATTACH] [ATTACH=CONFIG]555774[/ATTACH] [ATTACH=CONFIG]555775[/ATTACH] [ATTACH=CONFIG]555776[/ATTACH]

Finally I found a local welding shop who submitted a reasonable quote, if I supplied all materials and flanges including the mandrel bend tubes. After designing flanges in SolidWorks, getting those waterjet cut and purchasing all the tubing, I dropped everything off to the welder. Forty five days later with only about 20% complete, they bailed on the job... Luckily a professional welder friend of mine stepped in and helped finish the prototype set. Total cost on this set came in at $3500, only $500 over budget.

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I chose to go with all 316L stainless for these prototypes. After a bunch of reading I found that most cracks occur when two different grade metals are used. Sourcing matching radius mandrel bends of 2" & 2.5" 316L wasn't easy. Head and turbo flanges were cut from a single 1/2" thick 316L plate. Because there is no place for flexible bellows like the factory pipes, I chose a Vband configuration with custom made 316L flanges to connect the manifolds to the up pipes. This allows a little wiggle room on install, and a flex point for heat expansion when running. All the 1/2" NPT water ports and 1/8" NPT EGT sensor ports are also 316L SS.

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Learned a lot from building that first set. Making a couple design changes to the manifolds that should cut time and labor cost by about 10 hours or so. I'm getting ready to start on two more sets, so if anyone's interested in them let me know soon. I have a couple new bids on building these, but am also always open to suggestions.

Few more pics for anyone who wants to see what the jacketed or tube in tube process entails. Basically figure how long you think it should take and double it...

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Installed and plumbed on the test engine.

[ATTACH=CONFIG]555786[/ATTACH]

Believe Hoodoo may some good pics of his custom set being built to share also.

Have you tried this company?

www.mesamarine.com

Believe I spoke with them couple year ago about building them. I'll hit them up next week.

I've talked to him a few times, probably a good source. But if I remember right they will need a set to copy.
Not sure if they meant they could work off a stock manifold or if they actually need a water cooled set to copy. I think the first set would be expensive, then less and less as more get built. At the time I thought he did cast but he told me the other day that they only weld.
They are pretty easy to cut and fit but hard to weld without warping.
Need to use an old block and heads for a jig.

Just popped into this thread, have not read much but I am very familiar with MDS in Sweden having been involved in countless MDS/Duramax/Konrad packages. If you are looking for a pair of exhust manifolds, you might want to shoot an email direct to MDS http://www.marinedieseleurope.com/en...es/vgt-series/ I'm sure replacement parts can be purchased.

Thanks Biggus. I ask both Sweden and TX contacts a couple years ago, they said only available as replacement to existing customers. This may have changed, so would like to hear what they tell someone else now.

One reason I've been focused on building SS headers with a universal Vband attachment, there is really no need to stick with the stock GM turbo location in a marine build. GM placed it there out of convenience to clear the hood and fit multiple vehicles. If keeping the with stock VNT turbo and power levels, then up pipes will need to be as shown above. However if you change to a T4 turbo design, then why not move everything out of the intake valley?

[ATTACH=CONFIG]555828[/ATTACH] [ATTACH=CONFIG]555829[/ATTACH] [ATTACH=CONFIG]555830[/ATTACH] [ATTACH=CONFIG]555831[/ATTACH] [ATTACH=CONFIG]555832[/ATTACH] [ATTACH=CONFIG]555833[/ATTACH]

The acceptation here may be when replacing the engine in a Bravo1 setup. Room between turbo and transom becomes an issue. As you can see below, routing the exhaust to factory thru-haul locations can be tight. This exhaust setup has a short 3" dia by 8" long inside tube dumping exhaust into the 4" dia outside tube which Y pipes off to each thru-haul with flappers. All engine cooling water exiting the boat sprays into the 4" pipe right back of the turbo, off a manifold of 3x3/4" tubes. The inside 3" tube keeps everything flowing in the right direction, and stops water from making it's way back into the turbo.

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I've been slacking on updates, but for good reasons. Actually started on a nice twin engine conversion with another forum member. So have been trying to put everything together to get things moving. Once it gets rolling I will start a new thread, but for now lets just say it's 40' and will be spinning WMD's and was previously twin 900's with 6's...

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Cooling System
 

Now that we have our engine together and ready to drop in the boat, we need to design the cooling system layout. The choices here will ultimately depend on how and where you plan to use the boat.. The easiest and most economical design is an open loop cooling setup, and what the first Duramax boat relied on. The only down side to this setup is lack of heat exchanger, meaning no long term salt water usage. I ran mine in the gulf a couple times, flushed it thoroughly with salt-away after each use. But keep in mind you have aluminum heads, end covers, water pump, and a water cooled turbo system that were never designed for that harsh environment. So let look at our cooling system parts one by one.

Starting out with the seawater pump options. The Merc 46-807151A9 with serpentine belt pulley below will work for most installations. This is the same impeller based pump found on a majority of small block and big block GM based engine packages. In an open loop setup, it will supply enough water to cool all the Duramax components up to about 650 hp. I designed a simple mounting bracket that attaches this pump to the front of the block in the mounting location show below. Bang for the buck this set does the trick fine.

[ATTACH=CONFIG]556631[/ATTACH] [ATTACH=CONFIG]556629[/ATTACH] [ATTACH=CONFIG]556630[/ATTACH]

For added volume performance upgraded, the Hardin 1075 replacement pump also fits in this same location, This one allows you to easily split the charge cooler from engine cooling supplies.

[ATTACH=CONFIG]556628[/ATTACH] [ATTACH=CONFIG]556632[/ATTACH]

Which ever setup you go with, be certain it has sufficient inlet supply line and good quality sea strainer. A flush out port and shut off valve are also worth plumbing in there before the pump.

I came across your thread my Father Bought a new cheetah deck boat 26' fast cat and put a duramax in it. He has built his own headers and all a very clean build. running 2200 rpm it runs 82 mph with imco scx drive with 32" prop If i remember correctly here is a link to it via youtube it was in performance boat mag as well.

https://youtu.be/SQdzUaWqPoI

if you want to know more or anything hit me up and I will get you in contact with my dad.
Good luck.

That's a cool build also. I believe we've spoken before, several years back when I was working on the Warlock.

I've wondered how the Cheetah and your dad is doing. Haven't seen anything new in a while. Fell free to post some updates like hours logged so far, issues and such.

as of now he has just started working on it again he had prostate cancer and went through treatment but now he is up and going again. since he has built his own headers, when I spoke to him last night he was going through a later version wire harness to run. He is trying to get it back up and running for 4th of July to run it in Havasu. He picked up a 35 foot advantage on memorial weekend with twin 502's and black hawk drives it was a steal of a deal. ill try to get some pics and info of hours run next time i go to Havasu to work on my boat project.

Charge Cooling
 

Once again apologies for falling behind on these postings. Been busy sourcing parts for an actual marinization project I'm working on. One of these parts fits with our next topic here, air charge coolers also known as an after cooler.

Biggest difference between an automotive setup and a marine setup is how we cool charged air, or boosted air. In a truck the charge air goes from the turbo to a big air to air exchanger mounted in front of the radiator then to the main intake. Reason they are so big, thermal efficiency on these air to air exchanger is very poor. However a water to air charge cooler can easily obtain 80-95% thermal efficiency when sized and supplied properly.

First thing you need to know, the charge cooler should be first in line off the sea water pump. When using a single stage pump, I run all the water to the cooler before even adding a pressure bypass. The outlet air temp of the turbo can exceed 450F under heavy load. We need to get this air into the sub or low 100's before feeding it into the engine. While there is plenty of cheap aluminum charge coolers on the market, pay close attention to the CFM and water flow ratings. Better to buy a good unit the first time than find out it can't do the job after you've plumbed it all in.

Popular on Volvo and Yanmar engines, these double pass breadbox style coolers are proven trouble free units that typically mount on the engine. With proper water flow [40gpm] they should work fine on a stock 6.6L Duramax. I wouldn't push them much above stock power levels though.

[ATTACH=CONFIG]557174[/ATTACH]
Specification: Double Pass Air, Single Pass Water, In Production Since 1991 O.E.M. Peninsular 6.5 GMC 300 HP @ 3400 RPM Air Flow 500-600 C.F.M. Air Temperature 'In' 187' F Water Temperature 'In' 80' F Water Flow 40 G.P.M. Air Pressure +15 (Hg) The 3800 would achieve: Air Temperature 'Out' 90' F Water Temperature 'Out' 82' F Air Pressure Loss 2 ("Hg) The Thermal Efficiency is 90.6 %

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Another unit I've tested with are the Frozen Boost coolers. Their largest units are actually very affordable, and capable of handling 1000hp diesel needs. Size does make them a bit awkward to mount on an engine, but each application is different. They are also an aluminum core, so using in salt water for extended periods without flushing will likely limit the life expectancy.

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Next thing to consider is mounting locations. If you move the OEM turbo, or are going for that clean OEM look, you'll likely be tempted to place the charge cooler above the engine. I have some experience with this setup that tells me not to do it. When I first purchased the PPE boat the cooler was on top of the engine and turbo as shown above. While it looked nice and clean, several cylinder walls showed signs of etching from water setting on top the pistons when I tore it down. I felt this was most likely due to condensation out of the charge cooler running down into cylinders after shutdown. While not an issue when the engine is running, heat soak after shut down could cause water droplets to form and drain directly into the main intake runners. I moved my cooler to front of the engine to insure it couldn't happen after the rebuild.

I'd much rather have a condensation puddle in the charge cooler mounted low, cause it gets blown into the engine where it's evaporated on start up. I know it's common on gas engines to place the coolers under the blower, but I can speak from experiences. My friend who recently removed his Frozen Boost charge cooler mounted above the transmission for servicing another issue, thought he had a core leak. He reported several cups of water drained out of the charge tube when he removed the clamps. After pressure testing the cooler, it was all from condensation...

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One design that took this issue into consideration was the Banks Marine intake which I recently purchased a pair of. While they mount directly on top of the head, Banks used an up flow design that puts the inlet below the cooler core and the intake runners above. According to his engineers, this condensation issue was his reason for this design. While it has a great design and a cupronickel core that can withstand harsh salt water environment, it does require 80gpm of water flow to function properly. That's more than a single stage Merc pump is rated for.. So it will take some heavy duty plumbing to feed this thing with the 900hp engines it will be cooling.

While doing some research on water flow and pipe size, I found a cool calculator that takes orifice sizes and pressures then gives a maximum GPM flow rate possible. Figured I should post these values here so everyone can use it when designing the rest of our cooling system layout.

.50" Dia @ 20psi = 23.31GPM
.50" Dia @ 30psi = 28.55GPM
.50" Dia @ 40psi = 32.97GPM

.75" Dia @ 20psi = 52.45GPM
.75" Dia @ 30psi = 64.24GPM
.75" Dia @ 40psi = 74.18GPM

1" Dia @ 20psi = 93.25GPM
1" Dia @ 30psi = 114.21GPM
1" Dia @ 40psi = 131.88GPM

1.25" Dia @ 20psi = 145.71GPM
1.25" Dia @ 30psi = 178.46GPM
1.25" Dia @ 40psi = 206.07GPM

1.50" Dia @ 20psi = 209.83GPM
1.50" Dia @ 30psi = 256.99GPM
1.50" Dia @ 40psi = 296.75GPM


Also here are some links on water to air charge cooling for your reading pleasure.

Banks design testing of the intake above.

Dragzine tech article on charge coolers.

UK provider of marine coolers.

That core in the last picture looks just like the core from my Yanmar 6LP after cooler. But the airflow in mine passes through the core twice, from the turbo through the core, around the back of the core, and then through the core again into the intake. The second pass of air through the core is actually on the side that water enters the core. There are fuel and power steering coolers in front of my after coolers though. I had wondered about modifying the engines to add larger after coolers but I don't think they make enough HP to warrant the effort.

http://i272.photobucket.com/albums/j...psuvp3irhu.jpg
http://i272.photobucket.com/albums/j...psy9iuprio.jpg
http://i272.photobucket.com/albums/j...psrggpi93q.jpg
http://i272.photobucket.com/albums/j...ps01nwsnx9.jpg
http://i272.photobucket.com/albums/j...pss7lbfhyy.jpg

Very similar looking core isn't it. Any idea who builds those? Banks switched it up a bit in his design. Rather than passing the air through twice, he passes the water twice. See the small bar separating the upper and lower halves tubes of the core above. The other end you can't see is capped off. Same principle, but cold water inters the top and exits the bottom half.

I'll let you know how good they actually work in a few weeks, there is two of those Banks intakes in my shop right now.

No markings on the cores that I could see. The oil coolers and heat exchangers are made by SenDure I think.

Hi Kidturbo,

I really appreciate the wealth of info you've posted. I've been scouring the web for a few years for info like this because I have been planning on converting my 17,000 lb aluminum commercial fishing vessel to a duramax from my old detroit diesel. I'm currently keel cooled and I was wondering if you had an opinion on water to air intercoolers when no raw water will be used. Do you think returning coolant from the keel cooler should be routed first into the water to air intake cooler or do you think warmed returning water jacket water would suffice? Also, do you have a suggestion on marine gears? I was looking for a marine gear that would bolt up to a duramax and provide 1:1 ratio so that I could use my current prop but I'm not sure which gears are up for this level torque. My current arrangement is a velvet drive, I fairly certain it would rip apart in the first five minutes if I were to keep it.

My conversion will be quite a bit simpler than yours as I have a large dry exhaust stack and virtually unlimited room in the engine room. The engine room does get hot and I was wondering if you would recommend plumbing my air intake directly to outside air so it stays cool. I certainly don't need more than 500 HP so if you think this is an unnecessary step then I'll simply draw air from the engine room. Also I appreciate your discussion on manifold temperatures. I currently run a water cooled manifold but I'd like to save as much money as possible in this conversion. Do you think I could adequately insulate the manifolds with customized fiberglass wraps? It seems like a tall order to me. Thanks for the great info you've posted so far!

I have zero experience with keel coolers, so no real idea how efficient they are. But in a normal setup you'd want to avoid cooling the charged air and engine on a single closed loop system. Unless there's a massive amount of coolant involved with a very LARGE efficient exchanger. The air charge under load can reach 400F and requires upwards of 40-50 gallons per minute of coolant flow alone. I would look at the KW rating on your keel cooler and compare that to the old engine setup KW and a Duramax power ratings for a better idea. You could test with that setup, then at worst just move the charge cooler to a stand alone seawater pump if it doesn't work out.

Since your not looking to exceed 500hp, I'd stick with the Velvet drive. Maybe freshen it up with some good clutches while out. There is a couple members on here who build them to hold 1000hp plus gas engines without issues. Check out http://www.hubermarine.com/performance.html for options. Another member is currently installing two behind 500hp units right now. Maybe he will reply with any mods he did to them. The only other good choices out there to handle the power with gearing you want are ZF and Twin Disk. Both make good stuff. I'm working on custom trans builds right now, and it's a pain...

On the exhaust and intake, colder air means less work for the charge cooler. But if you have a large engine room, just wrap all the exhaust good and you'll be fine. Plan on exhaust temps in the 1300F range at wide open. I've toured a few mega yacht engine rooms, they typically have water cooled manifolds and turbos, then wrapped dry stacks.

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here is the link for the water Cooled headers that my dad has made for the duramax motors that will be for sale.
https://www.facebook.com/25733290763...type=3&theater

Thanks Kidturbo. I think I'll try the keel cooler and see how it does. There's no way to determine its rated efficiency based on the specs because its just a series of pipes welded to the hull, not a manufactured cooler. Ocean water temps are 60 on the hottest day of the year and generally the faster the boat moves the more cooling power the cooler has. With my detroit I'm unable to load the motor high enough to budge my running temperature under any conditions, so there is definitely extra capacity built in. The return end of the cooler doesn't even get hot enough to kill the barnacles growing on it! I'm hesitant to start pulling any seawater into the boat because it can freeze, and I'd hate to rely on a rubber hose to keep me afloat. Thanks for the info on V drive, I'll look into keeping it.

Dean those headers are Bad ASS..

Chris

Velvet drives upgraded to huber 1550's
I think they machine the shaft to allow room for 11 disc's and add an oil pan for more capacity

Kidd, on the subject of charge air coolers, I may have a guy here who can handle that but when I look at higher hp stock units like from cat or Cummins, there are some that exceed the desired hp levels but I wonder how the higher rpm duramax would factor in.
I'm working on heat exchangers now and will start charge air coolers next, then pull everything out and finish the engine bay, run the tunes on the stands and put them back in the boat.

and no the boats not as ratty looking as the engine compartment is at the moment

Xx

Boat is looking great. I stole a peak couple weeks ago while in town. Its' time to order the main engine heat exchanger for my project to. Plus it fits where I left off in this thread. So far I'm leaning towards a 5"x27" Cummins OEM unit. Since you have good contacts down there, any suggestions on custom suppliers?

Just a note-the new supercharged scarab jet boats are using closed cooling. They have metal plates built into the bottom of the boat at the running surface that they use as a heat exchanger. We have not had any issues with them overheating even with the twin engine boats-they are packed in there pretty tight.

I saw those sweet little rides at the Miami show. Impressive design and interior layout. I was so busy checking out that SC setup, didn't notice the cooling system. Keel coolers have been used on lager vessels for long time. I've just never done much reading on them for smaller scale boats.

I've been laying out the cooling system components this week for a pair of big Dmax HP engines I built for another member. Even with Merc 1075/1200 style pumps, it's a chore to figure how much flow goes where. Because it's for ocean use, there is currently 4 heat exchangers per engine. Each with it's own flow requirements and restrictions. You'd think moving 200+ Gpm of water would make it easier. Not so much.... Hope to catch up on this thread soon as I sort out this design since it fits where I left off.

Kidturbo , did you ever get a handle on the water cooled manifolds ? I've worked with 304-316-321SS ,Inconel and Ti in exhaust systems and other fabrications , for
20 some years. If you need some help fabbing up some tubes let me know.

Always looking for good options on exhaust. Nothing has stood out as a superior design yet, not even my own. What I'd like to find is someone with access to mandrel bending equipment, along with great SS welding skills. That way I could drop off a mock up engine, and pick up a few sets a couple months later. I've spent more time just trying to get these two CMI sets bolted to the heads than most would tolerate.

What about casting a manifold? I have access to a development firm that can make the molds, and have contacts with a couple aluminum foundries.

The whole process is a pain in the ass.
I cut and fit mine on the engine at night in my garage and tacked them with a mig then took them to work and had them tig welded. Take them back home and find out their almost too warped to bolt back on.

That was actually my first approach with another member a couple years ago. Est was around 10k for first set, then about 2k for each pair done in stainless after that. Problem was, we only needed 1 pair at that time.. :D

Banks has a mold, probably collecting dust somewhere.