Maybe Mr Cool didn’t have a full kit? I chatted with Russ from Mr Cool and he had no problem recommending the right direction to go with his line for my 509s. I didn’t quite go in his direction, but if I find the 454/502 heat exchangers are overwhelmed in warmer water, I’ll make adjustments from his suggestions.

The CP Performance kit that seafordguy used on the tall-decks in his Tiger would definitely do the job for you. About $2k each I think.

Maybe so, but I told him (Brandon) I wanted a fully closed system and he didn't offer too much.......What he was interested in was the topic of the DD15 exchangers. I sent him pics of ecuchips fabrication DD15 exchanger for his perf. race boat.
For comparative size (he said) ...a typical Marine big shell and tube system is far inferior to a much smaller detroit diesel exchangers cooling capacity.......point taken, but the DD15 is not a designed (ready made kit) for boats and getting it there
would require much fabrication....... There's a used Merc 454/502 Exchanger on ebay $975 salt water used - too small & too expensive for a saltine.

Okay. I got it now… full closed cooling. I guess I missed that somewhere. That’s going to be much harder to do with any performance big block.

I’m only doing the blocks. Exhaust was never a consideration.

Interesting about the conversation around the Detroit cooler. Maybe a new product idea for them?

Tom that's just what I thought also....He sent all the pics of the fabricated dd15 conversion to his design shop.

Jas, I've got B&M 420s I need to setup with heat exchangers. I have the massive thermostat housing extension (alum) that has a big cast iron housing and outlet to the manifolds.

I really really like how you pull coolant out of the intake to the exchanger.
​​​​
​​​​The thermostat is under the black intake manifold connector?

Do you have a water circulation system for when the thermostat is closed?

Just seeing that unique CC system that's fabricated to fit in a small space ....for a blower race engine?....real credit to the designer & fabricator!

Totally...this is the type of revolutionary stuff that was happening in the early days of hotrodding. Re-purposing quality parts with some mods.

For minimal outlay, I can make fully cooled system and keep my Stainless Marine manifolds fresh for a lot longer. Vs a multi-metal exhanger that would likely cost $3500 USD for just 2 exchangers sufficient for 650-700 HP full system.

I'm also excited to get rid of the heavy extended coolant fittings that came with my 420s. Bonus. Less parts...less seals...gtg.

Those pictures alone are worth a thousand words!...my first & only intentions were to rid the corrosion from ocean salt on expensive engine components ( 2 Imco manifolds, risers, coolers) ets; etc; ~ takes a $$ toll.
Plus the benefit for a consistent engine cooling adds so much more attractiveness in this CC system........I'd love to replicate what Jas did and apply it to my engines .....again, the idea to close cool 1100 hp with
smaller & far superior system is enough said......I have to just jump in & find (2) - DD15's ....and not worry about the next step.

There used available that are cleaned and pressure tested.

Even if they are tested...you need to test them before you start the mods...or you could end up chasing an issue that is not your welds.

Yes I agree!.....generally speaking, would you know where to shop for a good condition "used" DD 15 EGR Cooler?.....

Try locally first. You can get hands on and inspect. You don't want to be buying someone else's problem. Try a place that services them.

Good link with some info on what they are, and that cleaning is common. So getting them cleaned up from carbon clogging is a thing...and should be available. They seem to last about 80k miles.

https://www.roadwarrior-inc.com/what...-we-need-them/

There are other sizes as well, if you don't need the 1200hp cooling capacity.

Important to note, that 316L stainless is really only good for low temp salt water contact.

Heat exchangexchangem...using raw water as the cooling medium, would stay relatatively cool. The engine coolant would be gtg of course.

If hot water salt water contact if required, titanium is the preferred metal.
​​​
304 stainless is good for fresh water lakes, but not that great for salt water, even cold.

Nice! what is the lenght/diameter of this?

Thanks T, that's great reading!.....my n/a efi 572's are just under 700 hp ...a lesser capacity than dd15 egr cooler would work...finding the right cooler(s) need a formula for that proper fitment.

I've been trying to get data on good simple formulas and rules of thumb for exchanger sizing. It's hard to do ..largely as the marine HE manufacturers don't use a BTU # for their various models.

I'm seeing putting oil coolers on that are 3"×22". Those would cool a SBC mIn coolant system. So pretty big, but if you want to run WOT continuously, you need some beefy BTU shedding systems.
​
I'm trying to see if the EGR cooler housings are also 316. The cores typically are...but I've seen 304 for the housings.

Depending on costs, I was looking at 1/4" stainless tubing, and fabbing up my own. The EGRs use flat rectangular tubing, vs the round...so they have better surface area for conduction.

Keep us posted T on your move to fabricate.....I'm a Jersey ocean boater nothing would be more suitable than CC for my engines. I take it your from bc Canada?

Yeah, from Vancouver Island.
​​​​​My Formula 233 has a full system for the SBC, so I don't need to do that one, but the Cobalt will need 2 exchangers. Helps that I have lots of bilge room to remote mount.

Nice...beautiful part of the world!.... wish you were closer for a joint effort......What size engines in the Cobalt?

Yeah, there is not many go-fast boats around here.

I've got 454HOs with 420 Blowers power Arnesons.

Doing rebuilds, the blocks were frost cracked when I got it....and fresh water cooled.

Orig Owner mentioned chine walking issues, so I'm not even sure I can use all the 650HP they were making before. I'll be porting the 088 heads and doing some basic cleanup.

I'll for sure document my process here with lots of pics.

Reviving this... I read through here and it doesn't seem like anyone found a good commercially available solution. I've been looking for a closed cooling system for an 1100hp marine engine with no luck. I called Perf Pro Tech a few months ago and they no longer manufacture their solution, which would have been perfect. The DIY setups many have made here are incredible but I have no problem admitting they're outside of my skillset and I don't want to risk ruining my engine investment doing it myself. Did anyone find a good solution here, even something that can be easily retrofitted from another application?

ecuchips's posts & fabrication for big hp seems to be in the capacity for a 1100hp application .....but like yourself, I also don't have the skill set.....he's halfway around the world!

Have you tried contacting Orca Marine ? They make industrial sized heat exchangers and many replacements as well. Just a thought

I'm still on the drawing board on what to do. Don't 'need' them just yet. The DD15 is 304 stainless housing with 316 tubes. Hot salt water and 304 stainless do no go well together. Zincs would be required for sure. Hot salt water needs titanium to be impervious. Even 316L does not like hot salt water.

I don't see the raw water getting too hot in the exchanger.

I was investigating fabricating stainless from raw materials vs the modded DD15. It's more about access to the stainless tube.

Are you twins or single? Why not run 2 exchangers in series to get your 1100hp capacity?

I appreciate everyone's thoughts above. I'm running a single. I would certainly run two in series, I just could not find any evidence of people doing that elsewhere (maybe I was picking the wrong keywords) and was hoping to get some validation before trying that. This is for a racing application so cooling is of course a huge consideration I don't want to get wrong. I will try to look into that further to see what people have done.

I would call innovation marine or Bam. I think they both ran closed cooled systems in engines that big years ago....

When in series, a dual heat exchanger would likely add some flow restriction. You'll have a circ pump on the engine, it should be ok for flow.

Raw water pump only has to pump through the exchangers...an oil cooler, PS cooler, maybe a trans cooler...then into the exhaust manifolds. No engine block/head flow restriction of a raw water cooled setup. Should be easier on the raw water pump.

A single would be far better for sure.

Not sure if that`s what youre asking but I run 2 coolers in series for oil.
Bellhousing cooler then to tube cooler.
I could have gone with a smaller cooler, the temps stay around 130ish cruising and 160ish at wot

https://cimg0.ibsrv.net/gimg/www.off...1af138878f.jpg
https://cimg7.ibsrv.net/gimg/www.off...20a885a9aa.jpg

On the Mercury 700's all of the coolers (engine oil, PS, tranny, fuel) get raw water. The only thing the exchanger with antifreeze is feeding is the engine block itself.

I would think the exchanger for the QC4V 1650 would be plenty adequate for any blower motor above 1000hp:

Cooling Components (mercruiserparts.com)

I spoke to Innovation and unfortunately they don't have any solutions north of 800hp. I spoke to Hardin a few months ago and they also didn't have any solutions. Will chat with Bam tomorrow.

302Sport - I had the same thought and was going through those parts catalogs last year. I think it is a potentially great solution. I don't see why it wouldn't work, but was hoping to at least pick a solution that confirmed worked for someone before investing the time, energy, and money to set it up and then potentially having to go back to square one. Perhaps I'll be the first to take the jump...

Yes I will be feeding raw water for everything else - antifreeze only for the engine.

I really like how ecuchips has that additional outlet in his heat exchanger for the ballast fill. I run a ballast tank that has an additional pickup on the transom, so another option would be two heat exchangers in series that each draw from one of my pickups and then can 'steal' from one of them when I fill my ballast. Could play around with multi stage water pumps to split the water (from one pickup) between each exchanger or even two water pumps, one for each exchangers, using both pickups. Spitballing ideas to overcome potential flow/restriction issues... Haven't thought the whole thing through so hopefully those ideas aren't too dumb.

For those following here is what I'm going to attempt:
-Two of these:
https://www.hardin-marine.com/p-7394...per-brass.aspx
-A two-stage water pump

1. Raw water enters boat / strainer / water pump
2. Raw water exits one stage of the water pump and enters Heat Exchanger 1
3. Raw water exits Heat Exchanger 1 and enters oil & power steering cooler combo
4. Raw water exits oil & power steering cooler combo and enters exhaust on one side
5. Raw water exits out exhaust

Then on Heat Exchanger 2:

1. Raw water exits the other stage of the water pump and enters Heat Exchanger 2
2. Raw water exits Heat Exchanger 2 and enters the exhaust on the other side

Heat Exchanger 1 & 2 will be mounted on top or next to each other outside of stringers.

1. Thermostat opens and coolant exits engine, entering Heat Exchanger 1 inlet
2. Heat Exchanger 1 outlet is connected to Heat Exchanger 2 inlet; coolant goes from Heat Exchanger 1 to Heat Exchanger 2
3. Coolant exits Heat Exchanger 2 and enters engine circulating pump

Those Hardin heat exchangers have 2 raw water outlets that are supposed to go one to each exhaust - I expect I will plug one on each, since each of my heat exchangers will only empty to one side exhaust each (assuming this makes technical sense)

The purpose of the above with a two-stage pump is to get equal temperature water into each heat exchanger for better efficiency, rather than having warmed up water exit one and enter the next.

Any thoughts on if I should have the raw water go to the oil & power steering cooler first instead of the engine heat exchanger?

Did you speak with BAM?.....interesting enough, he has a set of engine heat exchangers, brackets, tanks for both of his 1,000 plus hp engines that he fabricated quite a few years ago for his Cigarette.

All that seems like way more trouble than it`s worth and $$$$$$!!

MR. Cool will make you any cooler you want , quick and very reasonable.

https://www.mrcool.us/

$4k is a big chunk of change for the 2x BBC exchangers. Plus the mounting costs etc.

Dan mentioned Mr. COOL.

https://www.mrcool.us/coolers/univer...xchangers.html

They have some universal exchangers that don't have expansion tanks attached to them. So you can set up an expansion tank in a convenient location.

They may even make you a custom setup. Or a single. They should be able to place the outlets where you want them.

^^^^ agree 100%

They made me some custom fuel coolers in like 2 days and extremely resonable.

+3 For https://www.mrcool.us/

Thanks all. I ended up getting in touch with Marc at BAM and bought his heat exchangers. I did call Mr. Cool but they weren't able to make anything for 1000hp+ - I think the highest they said they could do was like 800hp? They do have a 1000hp oil cooler option though. Their sales guy was very nice.

For anyone who stumbles on this thread I did buy both of the BAM heat exchangers in a package together, but I only need one if someone is looking. Will edit this or post again if someone ends up buying the other from me one day.

Thanks again for everyone's help and advice! Will let you all know how it goes.