Guys is doesn't matter 80psi, 160psi or 240psi we were talking about boats and here is what you need to think about and what are you going to do to overcome this?

Go on yacht world and look at pics of small express style sportfisherman with little Cats and Cummins you will see one common trait in both engines the air intake pipe between the turbo and aftercooler has discolored paint of a burnt brown color from being hot and that is with 30psi boost max.

Unlike your truck/tractors the marine engine is closed in, when you start to build boost the pipes and engine room is cool as you run longer and longer everything gets hotter. The metal pipes when from 70deg to 140deg because hot air is running through them. The bilge air is also hotter and hotter.

So now you take air and boost it to 50psi it goes into a 140 deg pipe, the air picks up that difference from ambient plus the temperature from boost and this just multiples as it continues to run, make more boost and get hotter.

That is why the aftercoolers have to be sooo friggin large if you want to run the kind of boost pressures you guys suggest above 50psi to start with. Aftercoolers are not light and take lots of room, you need multi-pass because each row of coils can only do about a 20-30 deg F delta, you have unlimited water but it's summer for the most part the water is 70 deg plus.

How do you propose to over come this with the triple turbo high boost engines you suggest?

Let's start Thanksgiving right and start to map out a plan to build a marine engine here on paper that is pactical as well as functional.

That is one of the main advantages to compounds, less heat. My primary's made about 20 psi at an overall of 80 psi inter cooled between stages. At 50 psi the primary's where at around 10 hardly even working them. My EGT's would hold at 1250 on the floor.

You could also add a water to air intercooler or even a C02 coil to bring down discharge temps.

JD - not following the "water to air intercooler", you would want to drop the air temp before it enters the turbo charger - correct? If so that could work, interesting concept but you could only get down a few degrees below ambient. If you mean after the trubo(s) if you did not do that the engines would fail, run flat or just plain not make good power without them sitting in the bilge.

The CO2, ya those things are all good if you drag race, carrying gaseous products or anything like that is tough, you race for an hour almost or poker runs are long runs between stops, I think it could get tough and who would want to keep getting it filled?

The 20psi in a pimary to get 80 psi in the cooler, one of the turbo still needs to be putting out 80 psi doesn't it? I would think you are building heat through each stage regardless the air temperature would have to be the same 80psi creates X rise over ambient, right?

The EGT at 1250 - how long (time wise) do you honestly hold the pedal to the floor with a near full load? You know my next remark before I say it, so could we get data from someone who runs the triples on a dyno for longer periods or do they just not do that?

The water to air would be into the motor. A CO2 coil could run at a particular EGT level. For example it does not turn on until 1400 etc, just an idea have no idea how fast it would burn through it. No none of the turbos would run anyway near 80 psi. When they run like that at 10 to 10 psi that keeps EGT's down. My truck would hold that EGT for a long time no creep was going on. One time I was pulling about 15 k up a 5 percent grade, I rolled into at 50mph and accelerated to 110 and EGT stayed below 1300.

How much boost up that hill?

70 to 80

you run an air to air cooler, do you monitor temp after the cooler?

This is some fascinating stuff. I know nothing about diesels but my dream rig would be something along the lines of a diesel fifty Nor Tech or that 38 Powerplay with the Yanmars although i think the 43 NT Jassman built may top the list. I am really enjoying reading all your different angles on the subject course it's all Greek to me

JD do you have a pic of a triple set-up like yours not in the truck but on a stand?

Just had a stock inter cooler in my truck. No never monitored that, had 2 boost gauges and a pyro. Never needed to worry about it since the EGT's where so low.