P400 Turbo Diesel 4x4 Dually

I can see my boost easily run up to 11-12 under hard load. I dont worry much about the boost level but instead watch the EGT carefully.
(My engine is a stock compression unit)

Once the temp starts aproaching the lower end of the crispy zone I get my boot off the loud pedal and allow things to cool or at least keep the temp in a safe area.

Even at 10-12 psi the aftercooler is only marginally effective.

The air to air coolers come into their own when you get to 15- 20 on up.

For lower boost pressures I would really be inclined to recommend a water alky injection setup.

This adds power, keeps the little monster cool and also steams out the combustion chambers and they will stay far cleaner.

Best

Robyn

Thanks everyone.

The P400 was designed to run with a charge-air cooler on the HMMWV's... so it will be interesting to hear what the Franklin engineer recommends.

Many people have told me an intercooler will provided a noticeable difference in power.... that is why I plan to install this. I will also look into your water/alcohol injection suggestion Robyn.

;)

Increasing air flow through the 6.5 lowers EGT. I ran my stock compression engine at as high a boost levels as the GM-4 would go...18-19 psi below 2300 rpm tapering off to 11 psi at 3600 rpm...for thousands of miles. The GM-X series turbos are simply too restrictive on the exhaust side if you want to do anything besides daily driving.

With my 18:1 and my new turbo, I peak at 23-24 psi (for now) at 3600 rpm when loaded. Normal acceleration sees around 15 psi on a daily basis.

Stay at 8 psi if you want to, but you'll melt your engine down if you try to work it.

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Originally Posted by JetBoater

Thanks everyone.

The P400 was designed to run with a charge-air cooler on the HMMWV's... so it will be interesting to hear what the Franklin engineer recommends.

Many people have told me an intercooler will provided a noticeable difference in power.... that is why I plan to install this. I will also look into your water/alcohol injection suggestion Robyn.

;)

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Having an intercooler will lower boosted air temps by 100-200 degrees F, depending on lots of factors. A water/alc injection system can as well. However, adding both won't double the cooling effectiveness. It's all about delta T. Water/alc won't make a significant difference when combined with an intercooler - for most 6.5 owners. I tried water/alc on an intercooled 6.5, and found adding water didn't make a measurable difference in EGT (constant load on a 6% grade, then switched water on/off).

An IC is the best solution. It's always there; no space is lost to a water/alc tank & plumbing, no need to replenish a consumable supply, and no worry about winter freeze-ups.

Competition diesels are benefited from having both, mostly due to big boost numbers.

Jim

Sounds logical about the IC; in my case, although one would continue the concept of "logical", there's nowhere to mount one...

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Originally Posted by rustyk

Sounds logical about the IC; in my case, although one would continue the concept of "logical", there's nowhere to mount one...

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Who says it needs to be in the engine compartment? Think outside the box, with a couple electric fans. I would imagine there is all kinds of room under that thing.

Here is the Franklin engineer's answer.

Michael
Here is what they came back with on the Boost,

(max boost is 195 kpa or 28 psi)

Rod Townsend
Defense Business Development
W W WilliamsI would obviously require a bigger turbo such as a Holset HX35 to move into this range. I have no plans to go there.

I did ask for a "recommended boost level" based on my 20.2:1. I'm still waiting for that answer.

The motor pulls very nice over 2400 rpm... so I'll likely stick with the initial plan of rebuilding a GM-4 or GM-8 and running an intercooler.
;)

Rod did get back to me with more information on boost… he asked me not to post it as it may be misinterpreted.

Long story short, the more power… the more cooling capacity required. The cooling system on the 6.5 is designed for 195 hp /440 ft lbs of torque. This is inadequate for forcing further horsepower out of the engine.

He also advised that when moving up from 150hp to 190hp on the old AC1 to ECV…. a 30% larger Rad was required to cool the extra 40 horsepower.

Cooling is the key on this engine... so here is the plan:
An intercooler, 4” exhaust, less restrictive turbo, along with my high capacity cooling system in mint condition will assist longevity while “pushing” the engine hard. Oh… my extra oil capacity (15.5 liters/4 gallons) should help a bit too.


I do tow up a few mountain passes… twice a year, not a huge issue for me.
I’ll provide updates on separate threads as things progress.

I just towed my 32' travel trailer to Indy and back. It is 95F here today with high humidity. I never saw the coolant temperature exceed 195F and never saw EGT over 1050F pre-turbo. I am making considerably more than 225 HP at the wheels. The turbocharger is the key...

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Originally Posted by ronniejoe

I just towed my 32' travel trailer to Indy and back. It is 95F here today with high humidity. I never saw the coolant temperature exceed 195F and never saw EGT over 1050F pre-turbo. I am making considerably more than 225 HP at the wheels. The turbocharger is the key...

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OK RJ...you have left us in suspense for long enough. What turbo are you using?

Also, the links in your sig are dead.

Ron, if the turbo charger is the key, I am all ears... keep in mind that I don't have the 18:1 you do, and won't be running your 18-24 lbs of boost.

I just ordered an intake adapter from Peninsular for my upcoming intercooler project. The turbo is on my list of upgrades so your thoughts and recommendations are appreciated.

Now that the truck is dialed in and I finally am happy with it... boating season is ending for the year. Us salmon fishermen now switch from the larger Fraser river, to the smaller rivers in southern BC.

Here's a few shots of the truck ready for the fall fishing/camping season.

I have 3 foot wide by 5 foot long trailer bar for towing the jet boat behind the camper. It doubles as a step (not shown in picts).

http://i97.photobucket.com/albums/l2...r/IMG_1501.jpg

http://i97.photobucket.com/albums/l2...r/IMG_1502.jpg

http://i97.photobucket.com/albums/l2...r/IMG_1507.jpg

Interesting to me that ronniejoe's temps run the same as my duramax. Coolant and transmission oil usually run 100 degrees above the outside temperature. Works for me. Of course I haven't been in any desert locations where the temp. may be 125 or so, but when it hit 112 in Texas last summer, my temps were running about 210. Yeah, I know thats hot, but the stock cooling systems can't transfer anymore heat than that at least in my case.
So far no problems, nearing 130K miles. Some of my buddies have learned the hard way not to change out the grill to one of those fancey closed looking ones, they turned out to be an overheating problem, put the stock grill back on and problem went away.

old post but interesting.....

did you ever get pics of the inserts from your first post?

"My mechanic buddy is having this block repaired using inserts which are machined into the fractures of the block. I'll share photos after it has been done. Apparently they have been repairing cracked blocks for years... without issues. If it works, I have 2 more to fix.

My pics can be found in a separate post... see this link:
http://www.thedieselpageforums.com/t...ad.php?t=32921

I ended up selling the block along with all the parts some time ago. These fixes keep the cracks from getting worse. They also add a measure of strength depending on the lock or stitch.

I am a fan of these since they essentially save the blocks from the scrap yard.

;) Jetboater