High EGT,s on HX55 WM, 4x560 diesel endurance raceboat

I have questions

- is this 1350f EGT across all 4 engines?
- how much boost and fuel flow at egt?
- any chances of boost leaks?
- what are air intake temps?

-All about the same.
-40-41 psi, 29-30 US g/h at WOT (110-115 l/h)
-no boost leaks
-do not know for sure
 
Pictures.
 

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Taken the numbers you posted on RPM and boost and looking @ the inducer size compressor I would expect a max compressor flow rate of 86.47LB/min more than able to make over 650Hp.
Some things do not line up and not knowing your AFR unable to tell if your EGT problem is drive pressure or your simply running out of fuel delivery as for having to small injectors having end of injection to retarded dumping a load of exhaust gas into the manifold boosting your EGT up so knowing your start of injection and injector on time will give a clear picture on that part.
I also think that your engine is what we call a Patrol craft short: the engine able to give max power just to pull the boat out of the water and after this the engine will settle is self @ max RPM reducing engine power to about 320Hp? but better read engine specification sheet but some will only say 20 hours a year on 100% power or some kind of load curve that’s is not real clear on how to read it as more intended for commercial Bla Bla.
We test a load of Volvo Penta and MAN D28 and most will make 700 to 900Hp easy but COP can be a lot lower on these engines and for the ones that ignore these recommendations on COP whey simple need a lot mote maintenance on leaking/damaged exhaust system if it will stay with this only………….
All we have done on our race engines is use up to 30% bigger injectors and find a way to run the engines more efficient dropping EGT and even boost to reduce thermal stress on engine parts but in the same time finding ways to spool the turbocharger not getting a load of smoke but this involves remapping the ECU or ECM a lot.
I’m not going to comment on the ones that are able to build good injectors giving stability on good fuel delivery but all I can say we only use OE injector parts but yes hard to get as some are only produced during the test phase of an new engine build but good thing is Euro6 or Tier4 final engines intend to have bigger injectors so on some engines this can be a step forwards as well.

I hope fitting a bigger TH to your engine will help but cracking a water cooled manifold or water cooled TH can be catastrophic as gas entering the cooling system will drop coolant flow giving engine damage in the next two minutes so better save that sorry install a water coolant pressure sensor as common on most big diesel engines. Also think twice before machining a water cooled TH as we seen the fail often even in there original state due to thermal wear. For the most parts on non commercial applications due to large load variations. Also take in mind a water cooled manifold system takes a way a lot of heat so calculation a TH can result in up to 20% less exhaust has volume needing a smaller TH resulting in more drive pressure.

Just my opinion but hope there is an easy way out getting more power.
 
Just to expand a bit I have a 12.7 detroit diesel. At 1600 to 1700 i make about 600 crank HP. That's right at 30 GPH. Compared to your engines the swept volume over time is similar so the math should somewhat translate. My compressor is 71/100 but my turbine is 88/96. My post turbo EGT at only 36 psi rarely goes above 920. It might hit 950 at high elevation.

I agree with tall boy the sizing of the compressor wheels aren't an issue. Maybe they can be updated to a newer style but that will only gain so much.
 
What do these races entail? Wot for long stretches or is there some portions with less throttle?

Almost impossible to go WOT all the time. These water racetracks change all the time..
But when chasing longdistancerecords you look for nice weather and sometimes the water can be flat for long periods.
Then you want to use the power you have but the EGT,s get to high and you need to back down to 80% speed.
 
Ok But how often are you switching from say 20% to 100% throttle? Is this more of a record chasing event than a race with other boats?
 
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Boats are night and day different than trucks. I have customers ask me all the time to "hop" up their 12v in their 30-35ft boats... I say No! Egts, prop pitch, lobe angle, trans final gear raito come into to play and they have to like eachother

Not to mention boat motors are under 100%load almost 95 % of the time..
 
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We built a 65 ft sporty, with twin cat c32 acerts. Cat would t sign off on the boat until that boat could run cool at 2300r @ 43 knots with no smoke. It was all in the prop.
 
We built a 65 ft sporty, with twin cat c32 acerts. Cat would t sign off on the boat until that boat could run cool at 2300r @ 43 knots with no smoke. It was all in the prop.

Yup had the same issues when we use to repower boats, the owners didn't want to change props when we went from an old Detroit to a new cummins :doh: but I wouldn't sign off for warranty until they did.
 
Yep as seen this other way around. They did sing of but short of power takeoff from the engine running max RPM 80% load. Jet pump supplier says it up to spec customer want a HP upgrade as for short on speed. Makes you think as well. It all has to work together.
 
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