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Boredom project, LB7 dirtymax turbo on a 6.2

Superhondaz50

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So driving it around (the neighbors are hating me), when I floor it, I'm getting a ton of smoke coming into the cab (no doghouse yet). I took a go pro video and it looks like the collector didn't seal on the passenger side, buy I can't really tell. I'm gonna go to O'Reilly and get a set of aluminum collector gaskets and some gold rtv to try and seal it up, hopefully that works. It's also prob part of my low boost problem.
 

Bulldogger

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Gonna add a note, so the CDR connects in two places, to the intake mani, and to the oil fill tube. This is fine in a NA setup as the Mani is pulling a vacuum on the CDR. With a turbo, the intake is pressurized, so with the CDR installed, the pressure shoots right into the CDR and into the oil fill tube and case, kinda turns itself into a wastegate. So to make it work, you need to disconnect it from the intake mani, plug the Mani, then hook the disconnected part into the piping BETWEEN the air filter and turbo inlet, this will keep a vacuum on it, and allow your case to vent, without blowing seals from your boost.

And another snippet, some CDR valves are water fording ones, so they have two extra barbs for that. Mine is this type, I will be using a new standard CDR and plugging the fording lines, no water in the desert to ford anyways haha
My super-low compression 1987 6.2 would explode at every seam with that kind of pressure. Glad you diagnosed it. Sorry to hear of blown seals, but it's part of the process. It is very interesting following this thread and I'll join those who thank you for sharing this. (Fun side note, I have little to no obvious blow by, but boy is she tired.)

Bulldogger
 

Superhondaz50

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My super-low compression 1987 6.2 would explode at every seam with that kind of pressure. Glad you diagnosed it. Sorry to hear of blown seals, but it's part of the process. It is very interesting following this thread and I'll join those who thank you for sharing this. (Fun side note, I have little to no obvious blow by, but boy is she tired.)

Bulldogger
Yep
 
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Superhondaz50

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Well, out messing with the up-pipe this morning before work and noticed the #8 cylinder where the header bolts up is missing one bolt AND is leaking oil. I don't think oil should be leaking out a exhaust port, looks like it's been leaking a long time. Any ideas?
 
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Bulldogger

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Guy near me has a 6.2, appears in good shape, he wants just $500 for. But that's a ways from AZ for an unguaranteed motor. I decided to source a whole powertrain instead. Thought hard about the 6.2, as it would drop right in, but opted for MORE POWER!
BDGR
 

Superhondaz50

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Guy near me has a 6.2, appears in good shape, he wants just $500 for. But that's a ways from AZ for an unguaranteed motor. I decided to source a whole powertrain instead. Thought hard about the 6.2, as it would drop right in, but opted for MORE POWER!
BDGR
Nice! Ya, if this motor quits on me I want to do something different, LS is pretty straight forward, ideal would be a Cummins.
 

Bulldogger

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Nice! Ya, if this motor quits on me I want to do something different, LS is pretty straight forward, ideal would be a Cummins.
I hear ya.

I thought VERY HARD about a 4BT and nearly bought one.

If I had the space, i.e. a good shed or large garage, I would have DIYd a 4BT in there for sure. Considering how low my 6.2 compression is, I'm going to nearly double my Hp and torque by putting in a 45K mile 6.5 turbo setup.

Bulldogger
 

Superhondaz50

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Took off the up pipes today. Cut and re-welded them, that way all exhaust flanges fit perfectly bolted up. Still getting exhaust smoke in the cab through the doghouse opening. I'm wondering if the truck always smoked like that from the #8 cylinder. Got 7psi of boost, so with atmospheric pressure it's about 9psi, felt peppy, good enough. I think I'm going to build the doghouse, keep a fire extinguisher in hand and rock it as is, at least I can say I have a turbo HMMWV with fancy gauges.
 

patracy

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Great effort, but I think your main problem is the turbo itself. For what it's worth, the GM-4 turbo GM used on the 6.5 had 51mm inducer on the compressor side. And a exhaust side with a 51mm exducer. The Duramax turbo has a 60mm/61mm respectively. It's a lot more turbo than what the 6.2 would need.
 

Superhondaz50

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Great effort, but I think your main problem is the turbo itself. For what it's worth, the GM-4 turbo GM used on the 6.5 had 51mm inducer on the compressor side. And a exhaust side with a 51mm exducer. The Duramax turbo has a 60mm/61mm respectively. It's a lot more turbo than what the 6.2 would need.
I would agree. I'm prob gonna leave this right now, at least till fall, I have the option of getting a pedestal that'll hook up to my up pipes that'll fit pretty much any turbo, specifically a HX off a Cummins.
 

TOBASH

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I would agree. I'm prob gonna leave this right now, at least till fall, I have the option of getting a pedestal that'll hook up to my up pipes that'll fit pretty much any turbo, specifically a HX off a Cummins.
Saab used to use tiny Mitsubishi turbos In the 1980’s in the old version Saab 900 turbos. I wonder if that would spoil up faster.
 

TOBASH

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I've been toying with the idea of a 6.0 4L80E setup with a 76mm turbo.

Should give it a good kick in the ass.
So, large turbos work on gasoline engines because they push 6000RPM, gasoline is only 15% efficient so it makes more exhaust, and therefore they flow a lot of air.

Diesel engines turn lower RPM's, don't flow as much air, and Diesel fuel is about 40% efficient, so there is less exhaust airflow. Smaller cartridges that spool up faster with less exhaust volume are better, unless you're running a 4 engine setup at a tractor pull.

IMHO
 

Superhondaz50

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So, large turbos work on gasoline engines because they push 6000RPM, gasoline is only 15% efficient so it makes more exhaust, and therefore they flow a lot of air.

Diesel engines turn lower RPM's, don't flow as much air, and Diesel fuel is about 40% efficient, so there is less exhaust airflow. Smaller cartridges that spool up faster with less exhaust volume are better, unless you're running a 4 engine setup at a tractor pull.

IMHO
Makes complete sense. That 6.2 is redlined at 3k, I've only had it up to 2500 at 7psi, so at 3k I'd prob be pushing 10psi, just with a ton of lag. I'm gonna finish up my doghouse, then this winter prob convert it over to a HX35 sitting on a d-max T4 pedestal for better spooling.
 

Awol

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So, large turbos work on gasoline engines because they push 6000RPM, gasoline is only 15% efficient so it makes more exhaust, and therefore they flow a lot of air.

Diesel engines turn lower RPM's, don't flow as much air, and Diesel fuel is about 40% efficient, so there is less exhaust airflow. Smaller cartridges that spool up faster with less exhaust volume are better, unless you're running a 4 engine setup at a tractor pull.

IMHO
I understand that. I'm talking about a 6.0 LS with a 76
 
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