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Discussion Starter #1 (Edited)
OK, here is round 2 of this quest. Found a serial number 44264889 which is a CPL858 that came with the GM adapter plate and flywheel. The adapter plate in this particular setup is the 9 bolt model which will mean either the engine or transmission will be tilted. Note that this adapter plate does not have the threaded port for a tach sensor. I'll post the part number of the 8 bolt GM adapter plate as an alternative and I just found a second alternate which I'll call 5b. Sort of interesting that the parts list says this one takes 9 or 10 attaching bolts. The 2 top ones must attach to the head. Had never noticed this before. Many of the part number you'll see here are the same as the Ford adapter assembly. So here we go starting with the adapter plate assembly. As in the previous Ford unit the number will match the diagrams. As before, some part numbers may have changed but this is what Cummins shows.

5. 3916101 Transmission Adapter tilted
5a. 3910516 Transmission Adapter (not sure if this is tilted or not tilted)
5b. 3914428 Transmission Adapter (not sure if this is tilted or not tilted)
6. 3920447 Bolt to attach adapter to engine M12x1.75x40mm flange head 9 required(8 required on 5a and 10 bolts on 5b)
7. 3916094 Cover Plate
8. 3902735 Self Tapping bolts for Cover Plate M8x1.25x21mm 2 required
9. 3910270 Dowel Pin 2 required
10. 3910260 O Ring Seal
11. 3910248 O Ring Plug

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Next up is the starter, starter spacer, and bolts.

3926960 Starter (Denso part 128000-0545)
3906647 Starter Spacer (new number 3934080)
3910901 Starter bolts M10x1.50x55mm flange head 2 required
Note that these parts are exactly the same as the Ford setup

Now for the flywheel assembly

3913055 is the part number for a complete flywheel with ring gear
1. 3913056 Bare Flywheel
2. 3905909 Ring Gear 14.60" OD 146 Teeth
3. 3901395 M12x1.25x32mm hex bolts 8 required
4. 3900269 Plain Washer 8 required
For your info, the part 3 and 4 are swapped in the diagram as well but I made the part numbers match the diagram. Cummins does have a mistake every once in a while. In this case the made the same mistake twice. Probably just copied the Ford diagram.

As with the Ford no pilot bearing is not listed. The bearing for the standard GM is 15x42x13mm which is a number 6302.

128237

Below are photos of the 3 different GM adapter plates in order 5, 5a, and 5b. The GM stuff tends to be kind of confusing.
 

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Char,
Looks like a typo with 9 and 10, No 9 in the drawing and 10 would appear to be the dowels.
 

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Discussion Starter #3 (Edited)
Like me, you are overlooking some bolts. There are 7 inside the adapter and 2 at the very top on that vertical plate which makes a total of 9. The part 3914428 has 8 inside the adapter plus the 2 outside for a total of 10. The 2 dowels are in the outside perimeter to align to the transmission bellhousing and no where near the bolts that attach the adapter to the engine. Like most people, I had always referred to the tilted bracket as 7 bolts and had never paid any attention to those on the outside. I guess Cummins thought it might fall off with only 7 bolts. LOL. I just discovered that one with a provision for 10 bolts today. Talk about overkill. I'm really in question as to where those 2 extra bolts go. Don't see any holes in the head for them. There must have been some type of brace in the GM vans where those attach. Someone who may have disassembled one of those P30 vans might have a better idea.
 

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When I pull mine out I will be taking a look at the part number and bolt situation. And now that I see what the starter spacer looks like I am going to take a closer look to see if it's stuck on the adapter and I just didnt notice it when I pulled the starter out. I think the Ford uses the same pilot bearing that number looks real familiar, I think that's what.i got for my zf5 thats going in with my ford adapter.
 

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Like me, you are overlooking some bolts. There are 7 inside the adapter and 2 at the very top on that vertical plate which makes a total of 9. The part 3914428 has 8 inside the adapter plus the 2 outside for a total of 10. The 2 dowels are in the outside perimeter to align to the transmission bellhousing and no where near the bolts that attach the adapter to the engine. Like most people, I had always referred to the tilted bracket as 7 bolts and had never paid any attention to those on the outside. I guess Cummins thought it might fall off with only 7 bolts. LOL. I just discovered that one with a provision for 10 bolts today. Talk about overkill. I'm really in question as to where those 2 extra bolts go. Don't see any holes in the head for them. There must have been some type of brace in the GM vans where those attach. Someone who may have disassembled one of those P30 vans might have a better idea.
There are 10 M12 bolt holes in every FGT B series block. Those top two bolt holes are still 3" below the deck surface of the block.

GM Used a 15MM pilot therefore a 6302 bearing.

Ford used a 17MM pilot therefore a 6303 bearing.

I have not seen a GM adapter with a Cummins part number that was not tilted. All the ones in your pictures look tilted to me. The sides of the GM bellhousing are straight vertical and the 4 lower bolts in the cummins block pattern are perfectly horizontal/symmetrical. That last picture there looks just as crooked as every other GM adapter out there.
 

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Discussion Starter #6
Good to know about the top bolt holes. I wasn't sure if there were 8 or 10 in the block. Those last 2 are just below the head. There was mention that they did make a non tilted version but wasn't sure whether either of these were the one. That one might be super rare like the Ford version for a C6 automatic. I didn't believe that one existed until one showed up recently. It could be the other 2 are less tilted versions or earlier designs. Without having the parts it's kind of hard to judge them from the photos. There may well be a 4th part number I didn't find. It's sort of strange that Cummins had 3 different adapter plates for GM application. I did change the description in the one I said was non tilted to questionable like the 3914428. Try to make my data as correct as possible. In theory, the part numbers would indicate that 3916101 is the latest version. One thing I noticed is there appears to be a bellhousing bolt hole on the passenger's side of that one that couldin't be possible with 8 bolts inside the adapter. With 3910516 and 3914428 that bolt couldn't be there. Maybe it was redesigned for that.
 

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You sir are a god sense for all the detailed info. If I could buy you a beer or a case I so would.

Any how just went down to Summit Racing since there local in my town and they had the Advance Adapters small block chevy to my year NV4500, the 94 year granny low, bolt pattern. So from looking at solely the bolt layout it would seem for this specific bellhousing the first or in your terms #5 would be the one to Matt up the 4bt to a 94 Chevy NV4500.

Up next is to locate that specific adapter and check bolt patterns as well as clutch setup. Most likely will have to run an internal slave cylinder as my rig will be a drive drop from drive line.
 

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Discussion Starter #8
The #5 adapter plate is the latest model based on the part numbers. It will be the one with 7 bolts inside the flywheel housing. Any of them are small block Chevy pattern but that one has an extra bellhousing bolt hole that the other 2 don't have. With the adapter and proper flywheel the GM NV4500 should be a direct bolt up. To my knowledge, no internal slave for the GM setup. Those were all external, either mechanical or hydraulic. Just be sure your GM transmission has the proper bellhousing since that early transmission has an odd ball bolt pattern. The main thing will be to dig up the parts. They are out there but GM flywheels aren't extremely common. The vast majority of the P30 vans were automatics. The parts are possibly still available from Cummins but the price is frightening. CPP sells the 3916101 adapter new for $1991.96. Diesel Parts Direct has it for $1890.80. New flywheels are in the same price range and that doesn't include the ring gear. See what I mean by frightening. Chad McKinney sells the parts used for $995 + $64.95 freight. That's about 1/4 the cost of a new pair. Should you happen to get an adapter plate he also sell the flywheel only for $695 + $49.55 freight.
 

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Ya definitely frightening. I'm gonna do some hunting around and see if I cant source something. Worst case is I just bit the built and sell my current NV, as I know it will easily fetch 2K on craigslist. Might be able to have one of the handful of company's out there building the NV's from the ground up to possibly use the dodge casing but the lower gearing internals, cause as far as I can tell the bearings are all the same. The Advance Adapters bell housing that I got is there part # 712577 which is a direct bolt on to my year tranny. So only thing left to source would be the adapter plate as well as what flywheel will work with what clutch I finally decide to run. Still sorta exchanging emails with a couple clutch company's whom also offer a flywheel within there kit. As for the internal slave I think there are some of these clutch company's whit whom offer the internal slave cylinders but could be wrong, again if its all external slave cylinders that are options then well I'm gonna have front drive line issues as my front axle will be a driver side drop which the same side as the Chevy slave cylinders location, but an internal one would eliminate that.

For the adapter plate I would much like to get the '#5' one due to the extra bolt hole versus the rest ot them, seeing how the chevy bell housing only has 7 all together to mount to the engine side.
 

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You can get the GM flywheel brand new for 500$ish dollars from First Motion Products In MO. I just bought one a couple months back had 40ish some in stock.
 

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Discussion Starter #13
Live Free, the difference there is the one in you photo is not a genuine Cummins part but an aftermarket replacement likely made in China. Nothing wrong with that but the OEM part is horribly expensive.
 
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