Request advice - P400 coming

[Sharecropper]

I have just ordered a new P400 long block from Leroy Diesel. It will be installed in my M1028 in front of a new 700R4 Level 2 transmission from Bowtie already on hand. Having said that, I would like to invite comments on my next course of action.

Yes Doghead, I have searched until I am blue in the face and feel like I have read the Library of Congress on here.

The P400 will come as a fully assembled long block. I had planned to move all of my other stuff over from my factory 6.2, such as intake, IP, injectors, glow plugs, crossover, water pump, alternators, pulleys and v-belts. But now I am having second thoughts, and would like to consider adding a serpentine belt system and 6.5 IP and injectors. My thought process is this - it seems sacrilegious to pay upwards of $9,000 for the P400, which is capable of 250 HP NA, and then dress it with 30-year old CUCV technology and belt system. So I am leaning towards the serpentine system, but what to do about the dual altenators and dual voltage system? Yes I know about the Rosscommon conversion, but I am not sure that is the best way to go. What would be wrong with using a HMMWV dual voltage alternator to feed both 12-volt and 24-volt circuits? I thought about keeping the front battery as the stand-alone 12-volt power source, but then sit two (2) 12-volt batteries on the rear shelf wired in series for the 24-volt power source. Seems to me it would work, although it would require a complete rewiring of the truck, which I do not mind at all. Please chime in with your comments.

My goal is to have these decisions made and everything in place for assemply and install when the P400 arrives in 8 weeks. Thanks in advance for everyone's input.

 

[NDT]

Option b is the civi dual alt system for serp that was available for ambulances etc. Look for a GMT400 platform 6.5.

 

[Iceman3005]

If it where me, I would get a new db2-4911 pump then turn the fuel screw up, add some new higher pop pressure injectors.

Install a turbo, I know you didn't want to mess with it, but what a difference the turbo makes. Before the turbo it took almost 3/4 throttle to keep it at 70 mph. Going up a hill and speed would drop off quickly. Now that I have the turbo, what a difference. Barely have to touch the throttle and it stays at 70, and if I encounter a hill it takes only a slight increase in throttle to keep it at 70. Heck one day I was doing 80 up a 4% grade without any effort!

That engine you are purchasing is quite the beast. I bet that thing could take 400 hp and over 700 ft. lbs. of torque.

As for the belts, in my opinion I think the V-belts work just fine. If it where me I would just leave it like it is. I have never had any problems. Installed new belts 5 years ago and I just replaced them a couple of weeks ago. V-belts work just as good as a serpentine in my opinion.

Add water-meth injection, keeps the egt's down (no need to install an inter-cooler for the turbo) and it can add up to 100 hp.

 

[Sharecropper]

If it where me, I would get a new db2-4911 pump then turn the fuel screw up, add some new higher pop pressure injectors.
Install a turbo, I know you didn't want to mess with it, but what a difference the turbo makes. Before the turbo it took almost 3/4 throttle to keep it at 70 mph. Going up a hill and speed would drop off quickly. Now that I have the turbo, what a difference. Barely have to touch the throttle and it stays at 70, and if I encounter a hill it takes only a slight increase in throttle to keep it at 70. Heck one day I was doing 80 up a 4% grade without any effort!
That engine you are purchasing is quite the beast. I bet that thing could take 400 hp and over 700 ft. lbs. of torque.
As for the belts, in my opinion I think the V-belts work just fine. If it where me I would just leave it like it is. I have never had any problems. Installed new belts 5 years ago and I just replaced them a couple of weeks ago. V-belts work just as good as a serpentine in my opinion.
Add water-meth injection, keeps the egt's down (no need to install an inter-cooler for the turbo) and it can add up to 100 hp.

Thanks Iceman. Here is what I think I will do - When the P400 arrives, I will transfer my original and recently-rebuilt DB2 pump over to it, along with my lines and new Bosch 6.2 injectors, and then run the thing for a while to see how it feels. One of my goals, in addition to having a strong and reliable engine, is to have an economical engine to operate. And we all know that the only way to produce power is to burn fuel (was that Einstein that said that?). Because I already have the pump, lines, and injectors, I have nothing to lose or invest to see what happens. If my DB2 pump/injectors seems to starve the engine, all I have to do is upgrade to the larger pump and injectors. No biggie. If all this fails to provide sufficient power, I guess a turbo could be in my future.

Regarding the serpentine, the same mind-set is prudent. Because I already have everything to transfer over to the P400, I will hold-off trying to re-engineer the wheel until I see how things work with my original v-belt system. It will be an easy plug-and-play situation and all brackets will interchange. I will, however, install a new AC Delco 6.2 water pump because the serpentine water pump rotates opposite from the v-belt water pump.

This should be a fun journey. I will photo-document the whole process on my rebuild thread for all to see.

 

[85CUCVtom]

So jealous! I've been wanting to do this swap into my Blazer for a few years now. Have fun with the build- looking forward to seeing this build thread grow. Very interested to see how she fits in the truck.

As for the belt drive accessories, I would keep the v-belts. I would use what I have, get the engine installed and driving then re-assess to see what improvements can be made. Why spend money if you don't absolutely have too. Good luck! Post lots and lots of pictures!

 

[Iceman3005]

https://www.youtube.com/watch?v=O233fuYBPuw P400 OH YA!

 

[Sharecropper]

Yeah neat video. If you didn't already know, Peninsula Diesel went out of business a few months ago. Unique Diesel in Texas bought all the assets. I have an email to them now to see if they will continue to offer a HO CW rotation water pump which Peninsula offered for their marine engines.

I also understand the later model 6.5 CCW water pumps were redesigned to provide a 50/50 balanced water flow to both sides of the engine. Evidently the earlier pumps sent more water to the driver's side, which could be a contributing factor to the higher temps on the back side of the passenger side head. I have also read on one of the forums that these later 6.5 CCW pumps can be converyted to CW rotation by simply replacing the impeller. I thought I would look into this between now and when my P400 arrives.

 

[Sharecropper]

Looks like this has the information on the water pump -

https://www.steelsoldiers.com/showthread.php?158177-Water-Pump-Part-Numbers

 

[Iceman3005]

Rockauto might have it cheaper.

Sent from my SM-G928P using Tapatalk

 

[Iceman3005]

Part number acdelco 252611. $53 on rockauto.

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[Sharecropper]

Part number acdelco 252611. $53 on rockauto.

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I'm on it. Thanks.

 

[Iceman3005]

Looks like this has the information on the water pump -

https://www.steelsoldiers.com/showthread.php?158177-Water-Pump-Part-Numbers

That water pump is for a chevy 350 not a 6.2/6.5


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[Sharecropper]

That water pump is for a chevy 350 not a 6.2/6.5


Sent from my SM-G928P using Tapatalk

Yeah I discovered that and deleted my post but you beat me to it!

Thanks. I'm on RockAuto now.

 

[ken]

Flow-Kooler offers a HO water pump for the CW 6.2. I have one . It works great. Their part number is 1895.

 

[Burning Oil]

Need more pictures of your build.

 

[Sharecropper]

Need more pictures of your build.

It all starts at post #198 of my rebuild thread. I decided to keep everything together on my original thread instead of branching off into a secondary thread. You can access my rebuild thread by clicking the link in my signature below. Thanks.

 

[Burning Oil]

I'll check it out.

 

[camoyj7]

https://www.steelsoldiers.com/showthread.php?176113-Serp-belt-drive&p=2103522&highlight=#post2103522

 

[richingalveston]

I like the timing gear setup I put in my gep. the roller rockers are nice but they have issues, I am resolving these issues now with my Harland sharp rockers.

motor seams to have a lot less rattle to it with these parts.

 

[Sharecropper]

I like the timing gear setup I put in my gep. the roller rockers are nice but they have issues, I am resolving these issues now with my Harland sharp rockers.

motor seams to have a lot less rattle to it with these parts.

Rich I actually considered both options, but decided to leave my P400 intact as delivered from GEP. If I had planned to Turbo the engine, I probably would have installed the timing gear assembly and Harland Sharp rocker assemblies. But instead my goal is to have a strong reliable NA engine that runs cool and breathes.