6.2L Dream Build

[Tplane37]

i turboed my M1009 and ran 10psi on a stock engine..

I have access to a '96 C3500 SRW with the 6.5L / 4L80E in it (snapped a crank due to harmonic balance failure). The body of the truck is junk, but the drive train only has about 105k on it. I am curious, what all did you have to pull off the 6.5L to make the "kit" to put the turbo on your M1009?

My Civvy 85 C30 has a 6.2L in it out of an M1009, and well, sluggish wouldn't even begin to describe it. I eventually want to aim for the "Dream Build" or some variation of it that we come up with in this thread, but in the mean time, I want to do something to this 6.2L that I already have. I have a good deal of experience with performance upgrades regarding the 12V and 24V Cummins (even a touch on the 6.7L Cummins, tore one apart with 46 miles on it in 2007! Helping with research for one of the performance companies...okay, I was the grunt, but still!), and the 7.3L Powerstrokes (and the top ends of the 6.0L Powerstokes), I can change an oil pan gasket on a Powerstroke in less than 8 hours. But the shop that I learned all of that at absolutely REFUSED to work on the 6.2L/6.5L GM trucks, and the owner never told me why.

Also, I don't know all the numbers and designations on the Turbos, that is something I am still learning on. I understand the basic "workings" of them, and that small vs. large play different roles on when/where you want your power curve to kick in, but as far as knowing which turbo works where... I'm still researching.

 

[jdknech]

well i had to use
- upper and lower intake
- passenger exhaust manifold
-6.5 injectors (there shorter, and will clear the manifold better)
- turbo
- homemade wastegate controller
-and i turned up the injection pump 1/4 turn + a "tad" more

i then had a exhaust shop build me a crossover pipe, and a 3" straight pipe off the turbe that came out infront of the rear tire.. (it ran outside the frame rail) the exhaust work was under $150 total

 

[USAWEAPON777]

With the 6.2 being a v engine id probably go for a twin turbo setup as opposed to as running one into another which is known as compounding( due to space constraints). A healthy 6.2 would prob be able to spool 2 hx35's.

 

[Tplane37]

I did some more searching on the P400. Redundancy and inadequate information is what I came up with. So I decided to contact AMGeneral directly, we'll see what kind of response I get. Here's the message I sent, hopefully their eyes don't glaze over!

Greeting:

I am inquiring about the P400 Optimizer 6500 Engine (with full girdle replacing the main caps). I have found several write ups on this engine dating back to 2008, but have found very little on how/where to purchase the engine, and the available configurations.

I am a member of the SteelSoldiers.com community, and we have recently been discussing the "Ultimate 6.2L Build" for the CUCV vehicles that many of us already own, and for upgrades to our 2 1/2 Ton trucks that many of us also own, when a couple of members suggested the P400 short or long block as our building platform. We are very interested in the variety of configurations that we can obtain the P400 in, where to place our orders, and what pricing is set for the various available configurations, particularly:

(1) Short Block (rotating assembly with oil pan, without cylinder heads),
(2) Long Block (Short block with cylinder heads, cam and pushrods, and valve covers...without intake),
(3) Crate Engine (fully assembled engine, ready to drop in and run, including exhaust manifolds, possibly with cross-over pipe and turbo/supercharger)

In addition to pricing questions on the above configurations, we are interested in any other configurations available. We are discussing what our best options are for building a performance engine with comparable or better MPG's than our current 6.2L engines, and looking to build something more durable. With this in mind, there are a couple of other questions:

(A) Will the 6.2L components bolt to the P400 short block? To the long block?

(B) What is the compression ratio of the P400? What would it be with the 6.2L heads? The 6.5L heads? The 6.2L heads with a 0.010" thicker 6.5L head gasket?

(C) Is the P400 already setup for head studs? What size head studs/bolts are already utilized in the P400? Can the P400 be adapted to utilize M12 head studs and fire ringed heads?

(D) How much boost is the P400 designed to 'safely' accept? Is the supercharger availabe, and if so, where from and how much? (We are discussing a twin turbo (one turbo on each bank) over supercharger set up)

(E) What are the HP at RPM /Torque at RPM ratings for the various configurations of the P400? And do you have graphs available so that we can review the power curves. (Ideally, I would like to plug various numbers into my Desktop Dyno application to we can review potential effects of our modifications prior to assembly).

(F) what cam grinds are available for the P400? What is the bore? And Stroke? Are different pistons available for the P400? Price/Availablitly on different components?

I understand that I am asking a number of questions that you may or may not have the answers to. But this information is neccessary for us to configure our builds. Please answer what questions you can and provide any brocures that are available. And if possible, please copy this form to your reply so I can keep track of what I have already asked and the coresponding answers to prevent redundency in our furture communications. Additionally, some members will be interested in shipping costs, others like myself would be interested in knowing if we can pick up our engines at your loading docks (I travel to NE Ohio from Central Illinois monthly).

Thank you for your time, and here's to a good business relationship in the future. A final quetion would be: Is your company willing/able to provide a discount to SteelSoldiers members? If so, what would that discount be?

Respectfully,
Dustin ***

 

[wayne pick]

AM General is a contracted Government vendor. It is highly doubtfull they will sell anything to the general public. Here is one of many sources for 6.2-6.5-P400 engines. they range from short block 6.2,to drop in P400s, www.65engineparts.com... BTW a fully dressed P400 will run you 16 grand +,!

 

[Barrman]

Thanks for linking the diesel page books in Joe. I thought I did, logged off and haven't been back since.

Back to the books. They are a wealth of 6.2/6.5 knowledge. Want bigger exhaust and don't want to spend $800 to Stan's Headers? They have a template in the book to run 2.5 out of each stock manifold. I am using their wiring diagram to hook up a '86 and newer civilian glow plug controller on my 6.2 install in the M715. No temp sender, no glow plug card and it bolts to the engine out of the way.

However, we really are beating an almost dead horse here. Thanks to all the 6.2 haters that haven't posted on here yet by the way. Spending $16K for an engine that almost gets the power of a 15 year old 12 valve and P pumped 6BT is not exactly a smart thing to do. There are some applications where only a 6.? will fit and they are kind of stuck with it. However, if you are looking for power only. A 30 year old economy designed engine might not be the best choice. I have almost 5 6.2 powered vehicles and will probably end up with more, so don't think I am picking on them. However, my need is good economy, the ability to sit for weeks or months without the fuel turning into water and dependable low power driving. A 6.2 is perfect for that. Now, if a 4BT could be had for the same price. I might be writing things a bit different.

Interesting thread.

 

[Tplane37]

However, we really are beating an almost dead horse here. Thanks to all the 6.2 haters that haven't posted on here yet by the way. Spending $16K for an engine that almost gets the power of a 15 year old 12 valve and P pumped 6BT is not exactly a smart thing to do. There are some applications where only a 6.? will fit and they are kind of stuck with it. However, if you are looking for power only. A 30 year old economy designed engine might not be the best choice. I have almost 5 6.2 powered vehicles and will probably end up with more, so don't think I am picking on them. However, my need is good economy, the ability to sit for weeks or months without the fuel turning into water and dependable low power driving. A 6.2 is perfect for that. Now, if a 4BT could be had for the same price. I might be writing things a bit different.

Interesting thread.

I am planning to look into the books soon. As for the dead horse... I am actually surprised that it took 26 post before that came up! And I fully agree with you on the P-Pump Cummins (4BT or 6BT). Personally, my favorite diesel is the 6BT as they are simple to deal with, easy to tweak and tune, easy to get horsepower and torque out of for next to nothing, and as long as you don't let the injector pump run dry, the biggest thing you have to worry about on the 6BT is where to bend and weld your 11mm wrench to make adjusting the idle tolerable. I learned a lot about hot rodding the 6BT right after I got out of the Navy and for about 5 years after that from working in a performance diesel shop in Southern California. But one thing I never understood when working there is why the 6.2/6.5 was not only neglected, but avoided with a passion. I saw countless customers coming through the door wanting us to do anything from routine maintenance to full out power build with binders of technical data... but the owner of the shop always turned these particular customers away stating that he refuses to work on these engines, and only these...nothing more.

I have found that most shops are the same way, and those that will work on the 6.2/6.5 family know very little about them and merely state that they are a PITA to work on and that's why they don't like them. I don't buy it, there has to be something more. The PITA part I'll buy that excuse to an extent, but only to the point that it means that there are certain tricks that must be known about these engines. All engines out there have their good points and there bad. A Cummins is intollerant to running out of fuel for any reason...the IP will blow the rear bushing. The Powerstoke is intolerant to dust and fine dirt/sand... even though most turbos are intolerant to grains of anything getting into them, the variable velocity turbos on the Powerstoke are the worst about it that I know of, and lets not even get into the engineering failure of the heads on the 6.0 powerstoke and the genius who decided not to ensure enough firewall clearance to change a head gasket or enough frame clearance to change an oil pan gasket. Then you have the Duramax and their injector problems, which I believe Isuzu finally took care of after about 6 years of trial and error testing on through mass production of failed parts. The end story is the same with all the diesels, they all have their nitches, but that is where research and diligence pays of for a good mechanic...learning what to do with the engines you specialize in. And I have not found a reputable shop that specializes in the 6.2/6.5 family.

For the concept above is the reason I mentioned in the OP "If money is not a factor." I want to know the week point of these 6.2/6.5 engines, particularly the 6.2. I want to run this engine because everyone tells me not to, and because most technicians are afraid of it. I want to know what can be done to rectify the weakest link in this engine, and then what becomes the next weakest link, how to fix it, and so on.

And I am going to agree that we are "beating an almost dead horse" but not a "dead horse." Sometimes you just need to give the horse a little Ace to get him to calm down enough to have the vet come out to pull the nail out of the hoof that caused the abscess that is causing the horse to much pain to kneel down and eat. Given the time, care, and effort, the "almost dead horse" can be nursed back to health and back into the show ring making you money once again. It's all about perception.

***
I do, however, appreciate your input thus far. To keep this thread going, I have attached another PDF about a high performance 6.2/6.5 crossbreed built by Heath Diesel. I am curious why he would have gone with the 6.5 heads, but modified them to accept the larger valves of the 6.2... why not just rework the 6.2 head? What is different?

View attachment 500hp 6.5L Diesel Race Engine - Heath Diesel, Inc..pdf

 

[5m0k3y]

a quote from 2MuchJunk off Deisel Bombers
"A 6.2 head will bolt to a 6.5 the only problem is the injector is at a different angle and can cause problems putting the injector line on and clearance between the injector and the turbo."

 

[wayne pick]

My Banks turboed 6.2 does everything I need it to do. I can merge on to the highway without getting killed, and still get great fuel milage with it if I only use the turbo when I need it. The 6.2 was never ment to be modified. It was built for fuel economy. The block casting and cast iron crankshaft are too weak to withstand any high horsepower modifacations. With the price of fuel going up every day, Im happy with the fuel milage im getting, about 25mpg with a 700-R4 and 285/16 tires.

 

[Tplane37]

a quote from 2MuchJunk off Deisel Bombers
"A 6.2 head will bolt to a 6.5 the only problem is the injector is at a different angle and can cause problems putting the injector line on and clearance between the injector and the turbo."

I haven't seen the exact post you referenced, but similar information is available in another thread on that forum that I have been reading.

http://www.dieselbombers.com/6-2l-6-5l-performance/68582-6-2-performance.html

My Banks turboed 6.2 does everything I need it to do. I can merge on to the highway without getting killed, and still get great fuel milage with it if I only use the turbo when I need it. The 6.2 was never ment to be modified. It was built for fuel economy. The block casting and cast iron crankshaft are too weak to withstand any high horsepower modifacations. With the price of fuel going up every day, Im happy with the fuel milage im getting, about 25mpg with a 700-R4 and 285/16 tires.

The fuel mileage is another reason I am interested in the 6.2L. I am more interested in higher torque than higher horsepower, but obviously, increasing the output of one will increase the other as well. Some of the structural issues with the block (provided we are starting with a good block, meaning no cracks, etc.) can be improved by having the block cryogenically processed which will "correct" some of the molecular imperfections by equalizing their "layout" in the casting.

As for the crank, I have read that the crankshaft is a weak point, but mostly from a collateral damage perspective due to a spontaneously failing harmonic balancer and/or weak main caps. This leads to more questions, of course. The issues with the main caps can only be addressed so much without changing the block casting itself (such as with the P400 6500 block). But what about the crankshaft? Are their forged cranks available for the 6.2? Where can I go to find the specs on the main and rod journals? At one point, I had found a company that could custom grind just about any crank you could come up with, I remember having a discussion with them about a custom ground crank shaft for a high HP 4.3L GM V-6 back in 2004. The pricing wasn't to extreme, but it wasn't cheap either. I also know that I can get custom ground cranks for my Hudson and Terraplane straight 6's and straight 8's... this leads me to believe that the 6.2 should also have something out there to take care of a weak crank shaft.

Also, with the recomendations that the harmonic balancer on a 6.2/6.5 be changed religiously every 100k miles, one would presume that there is a performance upgrade for these as well. And thinking about my Hudsons, their blocks are balanced and blueprinted from the factory (and their blocks are actually a chrome-moly type variant)... how well would balancing and blueprinting the 6.2 work out for us? The article I posted above about the race engine implies that this was done (as well as other fairly extreme measures) and that the 6.2 connecting rods were used for strength reasons.

And I am still looking for the exact differences between the 6.5 and the 6.2 heads. I have read that putting the 6.5 heads on a 6.2 makes a screaming bandit... for a short while, until the EGT's get to high and that's all she wrote. But if the valves on the 6.2 are larger than the 6.5, all I can think of is that the intake/exhaust runners are different between them and/or the precombustion chambers are different. But which one is the cause of the massive gains from putting the 6.5 heads on the 6.2, and what can we do to keep this combination from grenading the engine shortly after the build?

 

[Barrman]

Glad you didn't take offense about the BT comments. I have run into the same thing when looking for parts. Here is the tip off for me. The owner of the local race engine machine shop has a bone stock 6.2 in his daily driver truck. He heard me pull in with my 6.2 powered Suburban and came out to see what it was. We got to talking. Same things that have been discussed here. New IP every 5-10 years, new balancer every 100K. Change the oil, keep the glow plug system working and don't be in a hurry. It will last forever and get great mpg's. Plus, replacements are dirt cheap.

There were I think 5 different pre combustion chambers offered in the 6.2/6.5 series. Mixing and matching them leads to really different power rates and economy rates. However, everytime you read about this part put on that engine. You really need to find out which IP they had and what injectors. There are dozens of DB2 model numbers out there. Each is slightly different from the other. Some could be the same as another and some are so different you have to run different injectors for the engine to even idle. Put a turned down 6.5 IP on a 6.2 and it will feel like a new engine. Put an early 6.2 pump on a J code 6.2 and you will think half your engine is missing.

So, if somebody is going to list out what the "dream engine" is going to be. Please include block casting, head casting, precup number, injector model, the entire DB2 number and what results you got.

 

[Tplane37]

Glad you didn't take offense about the BT comments. I have run into the same thing when looking for parts. Here is the tip off for me. The owner of the local race engine machine shop has a bone stock 6.2 in his daily driver truck. He heard me pull in with my 6.2 powered Suburban and came out to see what it was. We got to talking. Same things that have been discussed here. New IP every 5-10 years, new balancer every 100K. Change the oil, keep the glow plug system working and don't be in a hurry. It will last forever and get great mpg's. Plus, replacements are dirt cheap.

There were I think 5 different pre combustion chambers offered in the 6.2/6.5 series. Mixing and matching them leads to really different power rates and economy rates. However, everytime you read about this part put on that engine. You really need to find out which IP they had and what injectors. There are dozens of DB2 model numbers out there. Each is slightly different from the other. Some could be the same as another and some are so different you have to run different injectors for the engine to even idle. Put a turned down 6.5 IP on a 6.2 and it will feel like a new engine. Put an early 6.2 pump on a J code 6.2 and you will think half your engine is missing.

So, if somebody is going to list out what the "dream engine" is going to be. Please include block casting, head casting, precup number, injector model, the entire DB2 number and what results you got.

Now that is something to consider! I guess a starting point would be to make up a database with all of the available variations... Then hopefully we can find folks that have ran at least some of the combinations for feedback on there results. Now it's getting even more interesting.

 

[dragogt]

Now that is something to consider! I guess a starting point would be to make up a database with all of the available variations... Then hopefully we can find folks that have ran at least some of the combinations for feedback on there results. Now it's getting even more interesting.

Most of you're questions can be answered here..

http://www.thetruckstop.us/forum/forumdisplay.php?218-6-2-and-6-5-Technical-Reference-Library

http://www.thetruckstop.us/forum/forumdisplay.php?229-6-5-Performance

TTS Is The site for 6.2/ 5 info..

 

[wayne pick]

If you are dead set on building a 6.2, the 599, 929 and 1982 660 "red block" are most desireable. Most 660 blocks other than the 82 red block were prone to cracking. I have a red block that was rebuilt 75K ago. It is in storage for that rainy day. Diesel power magazine did a nice 82 red block build. www.dieselpowermag.com.

 

[dragogt]

Now that is something to consider! I guess a starting point would be to make up a database with all of the available variations... Then hopefully we can find folks that have ran at least some of the combinations for feedback on there results. Now it's getting even more interesting.

Most of your questions can be answered here..

http://www.thetruckstop.us/forum/forumdisplay.php?218-6-2-and-6-5-Technical-Reference-Library

http://www.thetruckstop.us/forum/forumdisplay.php?229-6-5-Performance

When it comes to 6.2/ 5 tech and performance TTS is leaps and bounds ahead of everybody else....

 

[dragogt]

Ok so for what feels like the third time posting this...

Most of your questions have already been answered; Take a look at http://www.thetruckstop.us/forum/forumdisplay.php?218-6-2-and-6-5-Technical-Reference-Library and http://www.thetruckstop.us/forum/forumdisplay.php?229-6-5-Performance

There has been some big improvements made in the lowly 6.2/ 5 world thanks to them; Take a look around there is even 3 or 4 venders dedicated to these engines...

 

[southdave]

I had 3 rebuilt last Oct. worth every penny. Apparently the Rods have issue took 4 engines to get enough for 2 engine the 3 were knew, and it took 10 to get eight..

 

[Tplane37]

If you are dead set on building a 6.2, the 599, 929 and 1982 660 "red block" are most desireable. Most 660 blocks other than the 82 red block were prone to cracking. I have a red block that was rebuilt 75K ago. It is in storage for that rainy day. Diesel power magazine did a nice 82 red block build. www.dieselpowermag.com.

How do you tell the difference?

 

[wayne pick]

Block casting numbers are below the drivers side head on the rear of the engine block. All CUCV trucks will have the 14022660 engine block casting number. If the last three digits in the casting number end in other than 660, the engine is not original and was swapped out. The 1982 660 "red block" was produced for only one year, it was painted Allison red. Engines produced after 1982 were all painted black.

 

[Tplane37]

Makes me want to go out and look at my engine tomorrow...