[Detroit-Diesel]

Hey guys, new to the site. Was wondering if anyone has any ideas or ever heard of anyone making a stroker kit outta a 6.2 with 6.9 parts. I found a few threads but nothing real concrete. Thinking about buying a cheap 6.9 and playing around with a junk 6.2. Any thoughts if this could be done??

 

[bobbywalter]

What?

The db2 pump.....or the actual engine?

That ... Have you seen a 6.9?

 

[Detroit-Diesel]

I've been around them very little. I mean pistons and rods. Couldn't you bore out a 6.2 to 6.9 pistons and have a crank build for the rods? Is that even possible? I'm not entirely sure just looking for input. Thanks

 

[OkDually]

I've been around them very little. I mean pistons and rods. Couldn't you bore out a 6.2 to 6.9 pistons and have a crank build for the rods? Is that even possible? I'm not entirely sure just looking for input. Thanks

Bad idea..
The 6.2 and 6.5L blocks are known for poor metallurgy issues with thin cast blocks and are known to crack the webs and mains in stock form.

 

[Detroit-Diesel]

Bad idea..
The 6.2 and 6.5L blocks are known for poor metallurgy issues with thin cast blocks and are known to crack the webs and mains in stock form.

How about a p400 block. If money wasn't a problem what would you guys do. I hate to throw the idea away. I think it would be neat to do but that just my 2 cents 🤷

 

[OkDually]

How about a p400 block. If money wasn't a problem what would you guys do. I hate to throw the idea away. I think it would be neat to do but that just my 2 cents 🤷

Although the P400 is the more robust block ( metallurgy changes and block thickness) it will still be prone to cracks

 

[ProCycle]

With a turbo diesel it's much simpler, less expensive and more reliable to increase fuel and boost than it is to try to increase the displacement.
Also, just increasing displacement won't really make more power without also increasing fuel and adding boost to burn the additional fuel.

Even a N/A 6.2 will have much bigger and better power gains with a modest turbo system than it would ever have by increasing the bore or the stroke.

 

[Detroit-Diesel]

I'm very familiar with 6.2s and 6.5s but this came to thought and I would like to eventually accomplish it just to be a rebel I guess. I take the IDIs as a challenge you could say. If money was limitless to the sky and back, I was just wondering what all would be needed to do such thing. Even if a custom built block was needed. Sorry if I didn't fully make myself clear. Any help would be appreciated. Thanks

 

[OkDually]

I'm very familiar with 6.2s and 6.5s but this came to thought and I would like to eventually accomplish it just to be a rebel I guess. I take the IDIs as a challenge you could say. If money was limitless to the sky and back, I was just wondering what all would be needed to do such thing. Even if a custom built block was needed. Sorry if I didn't fully make myself clear. Any help would be appreciated. Thanks

You're in the realm of un-obtainium with an old horse.. Thanks to the GM bean counters and Engineers
If you're looking for 6.9 torque and power then finding a Duramax block and building it up would be more suitable to handle those needs..

 

[ProCycle]

You're in the realm of un-obtainium with an old horse.. Thanks to the GM bean counters and Engineers
If you're looking for 6.9 torque and power then finding a Duramax block and building it up would be more suitable to handle those needs..

Or just swap in a WHOLE 6.9

 

[Detroit-Diesel]

I was mor

You're in the realm of un-obtainium with an old horse.. Thanks to the GM bean counters and Engineers
If you're looking for 6.9 torque and power then finding a Duramax block and building it up would be more suitable to handle those needs..

I was more interested in making a 6.2 stroker just for the fact that no one has done it. It's a not about how much power or torque I can get, its just the simple fact that I would like to do it. Thanks

 

[ProCycle]

I was more interested in making a 6.2 stroker just for the fact that no one has done it. It's a not about how much power or torque I can get, its just the simple fact that I would like to do it. Thanks

A stroker could certainly be built but I can't see how parts out of a 6.9 would be helpful in any way.

 

[Detroit-Diesel]

A stroker could certainly be built but I can't see how parts out of a 6.9 would be helpful in any way.

I just figured since the bore is very close to the same that maybe you could bore out a 6.2 to fit a 6.9 piston. Or are the walls too thin to make this possible?? I have no clue. Never done anything too major on a 6.2 yet

 

[ProCycle]

I just figured since the bore is very close to the same that maybe you could bore out a 6.2 to fit a 6.9 piston. Or are the walls too thin to make this possible?? I have no clue. Never done anything too major on a 6.2 yet

The walls are not thick enough to take much of an overbore. You could probably be safe boring it to fit 6.5 pistons. But there are lots of other critical dimensions besides the bore. Wrist pin diameter, deck height, valve clearance cutouts, etc. Also, the 6.2 and 6.5 pistons have Ricardo chambers to create turbulence. The 6.9 pistons also have the Ricardo design but it's critical that they align with the pre-combustion chamber to work correctly.

As far as using a 6.9 crankshaft - the cylinder spacing and main bearing spacing would have to be identical and the bearing journal diameters would have to be extremely close. Then there's the matter of how much actual room there is in the 6.2 block for a longer movement of the connection rods. Since you couldn't make the block 'taller' you'd have to have shorter connecting rods or pistons with shorter compression height so the longer stroke didn't push the pistons out the top of the block. Then there's the problem of attaching the GM flywheel or flex plate to the 6.9 crank and modifying a front pulley to work as well. And what about timing chain gears? Front and rear main oil seals?

Those are just the immediate concerns that spring to mind. No doubt there are a countless other details that would have to be sorted out.

 

[Detroit-Diesel]

The walls are not thick enough to take much of an overbore. You could probably be safe boring it to fit 6.5 pistons. But there are lots of other critical dimensions besides the bore. Wrist pin diameter, deck height, valve clearance cutouts, etc. Also, the 6.2 and 6.5 pistons have Ricardo chambers to create turbulence. The 6.9 pistons also have the Ricardo design but it's critical that they align with the pre-combustion chamber to work correctly.

As far as using a 6.9 crankshaft - the cylinder spacing and main bearing spacing would have to be identical and the bearing journal diameters would have to be extremely close. Then there's the matter of how much actual room there is in the 6.2 block for a longer movement of the connection rods. Since you couldn't make the block 'taller' you'd have to have shorter connecting rods or pistons with shorter compression height so the longer stroke didn't push the pistons out the top of the block. Then there's the problem of attaching the GM flywheel or flex plate to the 6.9 crank and modifying a front pulley to work as well. And what about timing chain gears? Front and rear main oil seals?

Those are just the immediate concerns that spring to mind. No doubt there are a countless other details that would have to be sorted out.

Very very true. You mentioned a few things I hadn't even thought of. Appreciate the info. Definitely alotta things to keep in mind. Would no doubt be quite a project. Would be neat to do it someday when the time is right. Again thanks for the info.