M1031 Build

[dkdiesel]

Made a few changes to the M1031 I recently picked up. 4" lift (ORD rear shackle flip, BDS front springs) 35's on black steel wheels painted green. Led headlights. Pretty happy with how it turned out, actually rides pretty good for a square body. Rear driveline angles are not right but I can't feel any vibration at any speed so I'm gonna leave it for now.

 

[Skinny]

Looking good! I dig the light bar.

Mine is very close to your setup and the driveshafts are butter smooth up to the top speed.

Best investments...overdrive and crossover steering. Well and the AC too.

 

[dkdiesel]

I'm guessing the light bar was not a military-installed part? It does work perfectly though so it's gonna stay! For now I'm gonna keep it as is, don't want to put much $$ into the drivetrain, I've got a 12v cummins and 47re that will eventually make its way into it. The generator/governor works well currently but I would like to install the Apec's controller and almost pulled the trigger on it the other day but can't justify buying the interface cable for just one install. I sent a PM to the fellow that was selling them a few weeks ago but have not heard back. I would be more than happy to buy it from him if I could get ahold of him.

 

[Mullaney]

Made a few changes to the M1031 I recently picked up. 4" lift (ORD rear shackle flip, BDS front springs) 35's on black steel wheels painted green. Led headlights. Pretty happy with how it turned out, actually rides pretty good for a square body. Rear driveline angles are not right but I can't feel any vibration at any speed so I'm gonna leave it for now.

.
Sharp looking truck!

 

[Skinny]

I'm guessing the light bar was not a military-installed part? It does work perfectly though so it's gonna stay! For now I'm gonna keep it as is, don't want to put much $$ into the drivetrain, I've got a 12v cummins and 47re that will eventually make its way into it. The generator/governor works well currently but I would like to install the Apec's controller and almost pulled the trigger on it the other day but can't justify buying the interface cable for just one install. I sent a PM to the fellow that was selling them a few weeks ago but have not heard back. I would be more than happy to buy it from him if I could get ahold of him.

I got one from B4Thunder many years ago but not sure if he is still selling them. I don't think he is. I don't think the programming is hard. Just need to know how many teeth on the tcase gear the pickup is reading . How much is the cable these days?

Personally I'm not a big fan of doing anything to the engine and trans. I think an LS with a 4L80 and air conditioning compressor is the cheapest way into a better truck if you can go gas. But the 6.2 stays for awhile for me.

 

[Keith_J]

I have an M1031 with functional generator and governor. I am designing a light turbo to mimic the Banks Sidewinder performance plus eliminate lag so it has boost from 1200 to 3600 RPM. Just 10 PSI but with modern technology. Twin turbos..twin variable geometry turbos . 200 to 240 Horsepower is what the pair will support. Don't know if the DB2829-4520 injection pump will move enough diesel. Needs 95 mm2

Once those are working, overdrive transmission.

I've gotten an honest 20 MPG at 45 MPH. But 12 MPG at 65 MPH. This engine is most efficient at 2000 RPM.

 

[Skinny]

8.1 is almost 500 foot pounds just sayin...

I'm guessing you are building your own manifolds? Do you have a build thread on this? I am curious...asking for a friend

 

[Keith_J]

8.1 is almost 500 foot pounds just sayin...

I'm guessing you are building your own manifolds? Do you have a build thread on this? I am curious...asking for a friend

Manifolds from lightly massaged 1-1/2 Sch10 stainless (1.9" OD, 0.109" wall thicknes). This pipe will match the oval port on the exhaust. Port spacing almost perfectly matches standard tee dimensions for this pipe size. I'm burning individual flanges like HMMWV headers..

Just waiting on delivery of parts. 50 amp plasma torch, Miller Dynasty GTAW, Solar B flux and argon back purge kit.

 

[Skinny]

Waiting

This will be epic. Condolences to the crankshaft.

Seriously I like the idea of two little turbos on the 6.2 for sure.

 

[Keith_J]

Waiting

This will be epic. Condolences to the crankshaft.

Seriously I like the idea of two little turbos on the 6.2 for sure.

There will be a control system monitoring manifold pressure and opening the turbo vanes to keep it under 10 PSI. Both intake and exhaust manifold pressures. Drive pressure limits the GMX turbo systems. The free.floating Banks Sidewinder only benefits higher engine speeds. Both systems are plumbing nightmares and thermodynamically less than optimum.

The Banks turbo is a twin scroll but fed from a common port. And the GM manifold feeds through ports for cylinders 6 and 8.

My design has minimum manifold volume, ensuring fastest spool. Only the slightest vane shift will be necessary for near instant boost. Almost like a positive displacement supercharger. Only without.the 50 HP penalty .

With EGT of 1100 °F, the cylinder pressure at BDC when the exhaust valve opens, is about 60 PSI. This is the exhaust noise, this pressure wave is the primary energy driving the turbo. Large volume manifolds waste this energy.

 

[Skinny]

I know nothing about turbo system designs other then the basics but the factory system is whack. Talk about design compromise in the manifold.

Also seems like the only source of a factory manifold is low quality aftermarket or used which isn't great either.

 

[Keith_J]

I know nothing about turbo system designs other then the basics but the factory system is whack. Talk about design compromise in the manifold.

Also seems like the only source of a factory manifold is low quality aftermarket or used which isn't great either.

Exactly why I am doing small twins. Computational fluid dynamics are now used to design modern turbos so I found turbo that were made by the millions for a European engine shared between multiple manufacturers.. Ford, Mazda, Peugeot, Citroen and Cooper used it on a free spinning 1.6 liter four cylinder mill. 5000 RPM at a pressure of 3 bar absolute is equal to a 3.1 cylinder 4 cylinder spinning at 3600 RPM and 10 PSI. Roughly 20 pounds mass of air per minute.

With these modern twins, 10 PSI of boost will be available at all engine speed. Meaning minimal exhaust smoke, unlike the Banks system. And at higher engine speed, minimal exhaust restriction, unlike the factory systems.

Other designs which work well use Holset turbo with entrance area of 14 square centimeters.. The turbo I selected have 8 square centimeter entrances..with two mounted closer to manifolds will work even better. And packaging the Barbie size Wuhan War Whistles is even easier as 2 inch diameter tube is perfect. And manifolds made from industry standard pipe fittings makes it way easy. Port spacing matches the length of the tees..

 

[dkdiesel]

I got one from B4Thunder many years ago but not sure if he is still selling them. I don't think he is. I don't think the programming is hard. Just need to know how many teeth on the tcase gear the pickup is reading . How much is the cable these days?

Personally I'm not a big fan of doing anything to the engine and trans. I think an LS with a 4L80 and air conditioning compressor is the cheapest way into a better truck if you can go gas. But the 6.2 stays for awhile for me.

Wow! looks like my thread got hijacked! I've been working on light duty diesel's for my entire career. Good luck to this guy installing turbo's on his 6.2 lol. We were involved with a 6.5 TD build years ago... Converted to mechanical pump, Hummer block, all the internal goodies that are available for the 6.5 to make it as tough as possible, ARP everywhere, performance turbo, custom injectors etc... Engine was blueprinted and clearances were correct. It made 300 hp at the tires on our dyno and it was clean. I was impressed. Engine was in a suburban with a 4l80e and was daily driven. The owner drove it like an old man and rarely used all of the 300hp. We did all the service work on it (LOF every 3k) without fail. The bottom end made it about 35k before the bearings started to give up and shed material. The cause of failure was overloading. Timing and fuel was set very conservatively. The bottom line is the rotating assembly on the 6.5/6.2's can't handle a bunch more hp/torque due to design. So unless u leave them alone good luck with any longevity.

The calibration kit is around $350. I will buy it eventually if I can't get ahold of B4Thunder. I've looked at the diagrams on both the stock setup and the apecs controller, wiring is no factor, I'm just being cheap on the calibration kit that I will never use again.

 

[Skinny]

Detroit Diesel - lesson learned

Sorry for the hijack. It's a shame that the only way to get something reliable is go with a $15k Navistar engine. I would be content with going with a new Detroit but having a grenade with the pin out isn't nice after spending $5k for a long block. Unless the newer stuff is ok. Maybe I'm wrong and the quality is better then the GM factory stuff.

I said before I'd be more then happy to take the calibration off of my controller if someone sends me a cable but only if he is no longer selling a turn key kit. I'm not going to step on his business of he is still selling.

Too bad it's not a Deep Sea or something with a more standardized interface cable.

 

[dkdiesel]

Detroit Diesel - lesson learned

Sorry for the hijack. It's a shame that the only way to get something reliable is go with a $15k Navistar engine. I would be content with going with a new Detroit but having a grenade with the pin out isn't nice after spending $5k for a long block. Unless the newer stuff is ok. Maybe I'm wrong and the quality is better then the GM factory stuff.

I said before I'd be more then happy to take the calibration off of my controller if someone sends me a cable but only if he is no longer selling a turn key kit. I'm not going to step on his business of he is still selling.

Too bad it's not a Deep Sea or something with a more standardized interface cable.

You are correct, it is a grenade with the pin out if you modify it. I personally think the majority of the issues with stock 6.2's in these cucv's is excessive rpm's due to gearing. Yes they will pull the rpm's if you hold the pedal down, no they don't seem to enjoy it. Leave them stock and they work just fine and usually for many miles, same with the 6.5's. The "hummer" blocks and the optimizer builds are fine as long as they are left STOCK or turned up conservatively and not beat to death. Personally, I wouldn't put a dime into building either a 6.2 or 6.5 unless I was happy with the performance of the engine in stock form. A 12v cummins puts them to shame on longevity and power output with the same or better mileage when tuned correctly. If my 1031 had an OD unit on it already I would leave the 6.2 in it as I don't need it to go fast but again I would rather take the cost of the OD unit and put it towards a drivetrain swap.

Programming the apecs wouldn't be an issue and I would rather do it myself so I fully understand the system and settings, thank you for the offer. I'm just being cheap on the calibration kit. If B4thunder isn't selling them anymore I would most definitely buy his calibration kit if was willing to let it go.

 

[Skinny]

I was always worried about the cruise rpm stock even with 37's. I'm much happier with the 4L80 and a tach now. I'm hoping that buys me some time. Speaking of it...probably should replace my balancer. It has been ten years.

I hate to say it, I think the 6.2 is an absolute pile of junk. But it makes cool noises, is very reliable, and doesn't drink a lot of fuel. So it's staying.

I just don't think the Cummins fits very well and I don't know where you are but they are approaching $8-10k for something with a quarter million miles on it.

There is no cheap diesel alternative to the 6.2 for this truck. I hate to say it but when that crankshaft let's go an 8.1 will probably go in.

 

[dkdiesel]

I was always worried about the cruise rpm stock even with 37's. I'm much happier with the 4L80 and a tach now. I'm hoping that buys me some time. Speaking of it...probably should replace my balancer. It has been ten years.

I hate to say it, I think the 6.2 is an absolute pile of junk. But it makes cool noises, is very reliable, and doesn't drink a lot of fuel. So it's staying.

I just don't think the Cummins fits very well and I don't know where you are but they are approaching $8-10k for something with a quarter million miles on it.

There is no cheap diesel alternative to the 6.2 for this truck. I hate to say it but when that crankshaft let's go an 8.1 will probably go in.

I wanted to do 37's strictly due to final drive ratio's but I am going to use this truck every now and then as a service truck and it was going to be a little to tall with 37's.

The cummins actually fits very well. They are getting a little spendy but I have accumulated a few over the years and we build engines and transmissions so for me it will work out well.

 

[chevymike]

There is no cheap diesel alternative to the 6.2 for this truck. I hate to say it but when that crankshaft let's go an 8.1 will probably go in.

Yep, that's my problem too. I keep trying to find a relatively inexpensive diesel alternative that swaps in without having to do a lift (i.e. Cummins needs a lift to clear front axle). I am fairly sure I have a failed head gasket or more likely, cracked head as I am loosing coolant but no leaks. Got a exhaust gas tester to check the coolant and see.

That said, I have a Gen VI 7.4L BBC I bought to swap in. Super low miles and cost less than a set of replacement heads for the 6.2. Just a pain as it adds another project to an already big project I have with the M1010.

 

[Skinny]

Yep, that's my problem too. I keep trying to find a relatively inexpensive diesel alternative that swaps in without having to do a lift (i.e. Cummins needs a lift to clear front axle). I am fairly sure I have a failed head gasket or more likely, cracked head as I am loosing coolant but no leaks. Got a exhaust gas tester to check the coolant and see.

That said, I have a Gen VI 7.4L BBC I bought to swap in. Super low miles and cost less than a set of replacement heads for the 6.2. Just a pain as it adds another project to an already big project I have with the M1010.

Is Gen VI TBI or MPI?

One nice thing is the big block fits right in with no issue regardless of the transmission. All the tough stuff is off the shelf same as the 8.1 engine. Not like a Cummins which yeah there are adapter parts but you are still putting something in there that didn't come from the GM factory.

Don't get me wrong, if I had an endless pile of money my M1031 would be 5.9 powered.

 

[Keith_J]

Head gaskets on 6.2 engines are a normal wear item. I'm in the same boat with my 1031. Most cast iron cylinder heads with induction hardened valve seats will crack since the hardened seat is very brittle. Furnace welding is a viable repair method that lasts since it leaves the material in a tough state. But hardened valve seats are required.

That being said, I have a source for such reworked heads at $325 each. Now if I can get my head gasket order filled..direct shipped from manufacturer.