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Highest HP ever out of a 6.5

6.5quest

6.5quest

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Location
Nordland, WA
So I am working on a friends 6.5 with a goal of 350 wrhp. So far the highest I have ever been able to achieve is 303 wrhp and 590 ft. lbs. What I would like to know is if any of you think this is possible and if you have any suggestions that I might not have thought about. I will talk more about the truck and what we are doing if this discussion takes flight.
 
It's possible, PEN has a 400HP 6.5 at the flywheel which would put you close to 350 at the flywheel. The problem I see is the bottom end of a 6.5 isn't really meant to take it for very long. Also what IP are you using? I don't think even the best DS4 is up to the task of supplying that much fuel. 100MM3 of fuel is roughly 300-325HP in a good diesel, but I believe even the hottest of DS4's can only output roughly 94-95MM3 of fuel. Obviously you can use propane and nitrous to get the extra fuel needed and WMI to try and keep the pistons from melting into ashtrays.
 
How did PEN get his flywheel HP numbers? Did he dyno just the motor or what? I was using a very well built motor when I worked at Heath Diesel along with nitrous, propane, water/meth, and every other bolt on mod available and put down 303 wrhp which would put me at about 375 engine HP at the most. What did he use? My one big disadvantage was that I only had a GM-4 turbo and didn't have the propane or meth to high. We are using a DS4 pump with Heath programing but are going to be using an A-Team non-waistgaited turbo along with 20:1 comp.
 
PENINSULAR's 400HP 6.5 is a twin turbo engine with a special hybrid IP that they build in house. It is one serious piece that they build on a very limited basis.
 
Oh, its Peninsulars marine engine with mechanical pump. I know what you are talking about now. I used to work with Matt a lot. I am more concerned with automotive motors, I helped build the Heath land speed truck with twin turbos so I know what you are talking about.
 
Well the good thing is it is not my money and I am just doing the install of all my old parts on a new truck with a brand new Diesel Depot motor. Why do you ask?
 
If you want to do a standard performance build you are stuck. As you know, there aren't many off the shelf "performance" parts available for these engines. There are some things that I would suggest, but they take a lot of... time I guess you could say.
 
I think the use of the ATT to lower backpressure significantly will help achieve higher RPM reliably to drive higher HP. Also make sure you have a good lift pump, Like a 10+ psi Walbro or Airdog. The whole FTB mod, some threads on it. Need to modify the lower IP fitting for sure with the rest.

That along with a custom cam grind to reduce the gap around TDC and higher lift would help. Would need better rocker arm assemblies and springs to achieve higher lift and RPMs reliably. Forged crank I suppose if its to be on the road a while.

If working with custom tuning, you can try modifying the DTC programming to allow higher TDCO than -1.94 which would allow higher base timing to allow a higher max advance at high RPM. Terrible for cold starting, but could give more high RPM power.
 
Here is what this build has as of now. Heath PCM, GM-8 turbo w/ Turbo-Master, 4" exh. w/ twin out pipes, 2.5" x-pipe, (pyro, boost, trans, fuel pressure, rear diff temp) gauges, Heath HO-Inj., PMD-Isolator, removed vacuum pump, Penninsular upper intake, #7 fuel resistor, aFe stage 2 intake, hood vents and fender intake, Snow/Heath 6.5 MPG-Maxx water/meth system, Heath propane injection system, Zex nitrous, custom built 20:1 comp Diesel Depot motor. Motor has ceramic coated pistons, extruded intake, heads, & exh. manifolds, new A-Team dual spline non-waistgated turbo w/ heat wrap, Fluidampr balancer, dual 16" electric fans, balance-flow cooling upgrade w/ Heath HO water pump, and is getting the "Feed the Beast" mod very soon. As for cams, I have seen different cams used on these trucks and have yet to see an aftermarket one work as good as factory on a non-marine engine.

If anyone can think of anything else to use I would love to know.

Thanks
 
Hey Ian!

Check out my sig - blew up the 6.5 and am now running an LMM...

You already know how to get to 350...:thumbsup:
 
6.5quest said:
Here is what this build has as of now. Heath PCM, GM-8 turbo w/ Turbo-Master, 4" exh. w/ twin out pipes, 2.5" x-pipe, (pyro, boost, trans, fuel pressure, rear diff temp) gauges, Heath HO-Inj., PMD-Isolator, removed vacuum pump, Penninsular upper intake, #7 fuel resistor, aFe stage 2 intake, hood vents and fender intake, Snow/Heath 6.5 MPG-Maxx water/meth system, Heath propane injection system, Zex nitrous, custom built 20:1 comp Diesel Depot motor. Motor has ceramic coated pistons, extruded intake, heads, & exh. manifolds, new A-Team dual spline non-waistgated turbo w/ heat wrap, Fluidampr balancer, dual 16" electric fans, balance-flow cooling upgrade w/ Heath HO water pump, and is getting the "Feed the Beast" mod very soon. As for cams, I have seen different cams used on these trucks and have yet to see an aftermarket one work as good as factory on a non-marine engine.

If anyone can think of anything else to use I would love to know.

Thanks
Click to expand...

Big Daddy lift pump, and perhaps some form of shielding around you guys at the dyno if she flies apart!
 
A couple thoughts come to mind here.

The bottom end of the 6.5 is not and never was designed to take the sort of power levels you are talking about in a truck application.

The engines that Peninsular builds are specialty Marine engines and they are equipped with water cooled aftercoolers as well as the fact that a marine engine has all the water in the pond to cool the beast.

A pickup/Burb has a limited ability to cool related to the size of the radiator and how much heat the engine is building.

300 HP at the rear wheels is a real nice accomplishment.

If you can keep this monster together and not melt it I would be happy at these numbers.

The Boneyard over at "Crispyville" is full of melted and mangled 6.5's that have been overfed in a quest for "MORE POWER"

Jim Over at TDP built up a 300HP rig (Shaft HP I believe) a few years back and it has been on the road many many K miles and has held up well.

The 6.5 was designed to withstand (reliably) about 200 shaft HP.

The cooling system and such was designed around these parameters too.

Even with all the cooling mods and everything working to its tip top you are approaching the limts of reliability here.

300 RWHP is nothing to sneaze at, especially with the torque that your getting too.


best

Missy
 
I believe the cooling system will not be an issue. The reasons the engine gets hot may not be the same on modded engine. If you have made it more efficient there wont be as much waste heat. So you keep temps in check even at higher power. Reducing the turbine drive pressure goes a long way to reducing waste heat in the system. WMI also helps as well as propane.

Now no one can argue with the bottom end blowing up, but he likely has a forged crank and at least a girdle from diesel depot, as well as being balanced and has a fluidampr
 
Yeah I am not worried about the cooling system either. My truck that made 303 was my daily driver and still is. We will detune the truck as soon as the goal is met to make the drugs work best for fuel economy and towing. The electric fans are going to be used for just the dyno run, after we will put back on the D-Max fan and Heath clutch w/ new radiator.

So Chris what do you think of that LMM, I am going to get a D-Max as soon as I am done with training and get my first billet. Good to hear from you again!
 
You will never go back Ian.....trust me!

The 6.5 is a fun 'budget' diesel, but the DMAX is in a whole 'nother league...
 
Nothing on my farm gets an easy life....every machine is expected to pull its own weight....

I do agree though - more and more of these trucks are just seen as grocery getters for the guys in the burbs...sad really...
 
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