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-   -   69 K20 NV4500 Converstion Questions (https://67-72chevytrucks.com/vboard/showthread.php?t=654158)

The Youngen 12-27-2014 12:58 PM

69 K20 NV4500 Converstion Questions
 
At the moment, i am building a 69 K20 and have a few donor trucks. The 69 had no engine but a SM465/NP205. 82 K20 Suburban with 6.2 Diesel with hydroboost system/TH400/NP208. 95 Chevy K3500 6.5 Turbo Diesel/NV4500/BW Transfer Case (Driver Drop). 71 C20 (originally 350/TH350) with no Engine/Tranny but everything else.

I'm going with the 6.2 for fuel economy, nv4500 and np208. The 6.2 has already had the heads off, cylinders and heads cleaned and reassembled. I'm sticking with the 6.2 course heads since they are in significantly better shape than the 6.5 heads and block. The turbo setup is going on the 6.2 with a double exhaust gasket. The NV4500 is attached to the 6.2 with the 95 bellhousing, new slave cylinder, new clutch. I was in luck that the np208 from the 6.2 was 32 spline so that was a bolt-up.

This whole setup is already attached to the frame via small block motor mounts.

So now the questions...
I'm planning on attaching the NP208 to the frame, same as the 205.
How do i support the NV4500/NP208? Which crossmember should i use? What mounts should i order? Im currently thinking about cutting out the center section of the 95 crossmember and welding in the 69, then use the 95 tranny mounts. Everything I've researched includes using the AA adapters.

I have 4 different crossmembers to choose from, 69 SM465 manual, 71 auto, 82 auto and 95 manual.

franken 12-27-2014 06:08 PM

Re: 69 K20 NV4500 Converstion Questions
 
The NV4500 has a mount and I doubt the NP208 does, so I'd first try the crossmember and mount from the truck that originally had the NV4500.
The NP208s generally need a new chain so you might want to check that.
The NP205 is about 1000 times better than the NP208 BTW, but has a less desirable low range and would need an adapter.

SunSoaked 12-27-2014 10:02 PM

Re: 69 K20 NV4500 Converstion Questions
 
I'm guessing the ONLY reason your using the 208 over the 205 is because its the older figure 8 style?

I have done something similar. If you search my posts you will see many useful pics of the 4500 I put in my 69 K20 (CUCV suspension). I used the 69 x-member but I moved it and the motor mounts 2 inches forward. This gave me room between the distributor, (not a factor 4 U) but even better it put the shift tower and stick dead center of the original shifter hole and cleared the bench seat.

I had to use a 2 inch spacer between the x-member and trans mount pad to level the drivetrain out. I used the factory trans mount. Don't forget the upper bolts are metric.

I did NOT mount the xfer case to the frame in anyway. That's a whole nother hotly debated topic.

SunSoaked 12-27-2014 10:14 PM

Re: 69 K20 NV4500 Converstion Questions
 
2 Attachment(s)
A few pics I found on my desktop.

72 Copper C-10 12-29-2014 03:59 AM

Re: 69 K20 NV4500 Converstion Questions
 
There is nothing wrong with a 208, they are way stronger than what people give them credit for.

The Youngen 12-30-2014 12:24 PM

Re: 69 K20 NV4500 Converstion Questions
 
I'm using the NP208 since it is lighter, has a better low range ratio and bolted right up with no modifications. The NP205 would require a lot of modification.

After more research, i decided against the transfer-case mount.

Thanks SunSoaked for the pictures and advice! After looking at your thread, I decided to use the stock 69 cross-member, 95 transmission mount and shim the difference. I'm going to use the factory motor mount positions since it will be better for weight distribution.

I'm not overly concerned about the strength of the NP208 since the engine will only be outputting 150 HP and 250 FtLb at best. Plus, only 1 out of a 500 miles will actually be in 4x4.

Redcap 12-30-2014 04:01 PM

Re: 69 K20 NV4500 Converstion Questions
 
Quote:

Originally Posted by The Youngen (Post 6977502)
I'm using the NP208 since it is lighter, has a better low range ratio and bolted right up with no modifications. The NP205 would require a lot of modification.

After more research, i decided against the transfer-case mount.

Thanks SunSoaked for the pictures and advice! After looking at your thread, I decided to use the stock 69 cross-member, 95 transmission mount and shim the difference. I'm going to use the factory motor mount positions since it will be better for weight distribution.

I'm not overly concerned about the strength of the NP208 since the engine will only be outputting 150 HP and 250 FtLb at best. Plus, only 1 out of a 500 miles will actually be in 4x4.

The 208 should work just fine for you then.

1972RedNeck 01-01-2015 10:03 PM

Re: 69 K20 NV4500 Converstion Questions
 
Quote:

Originally Posted by 72 Copper C-10 (Post 6975541)
There is nothing wrong with a 208, they are way stronger than what people give them credit for.

I've seen a lot of them shelled out behind stock 6.9 Fords - maybe the Chevy engine just isn't up to the task?

Redcap 01-01-2015 11:22 PM

Re: 69 K20 NV4500 Converstion Questions
 
Quote:

Originally Posted by 1972RedNeck (Post 6981060)
I've seen a lot of them shelled out behind stock 6.9 Fords - maybe the Chevy engine just isn't up to the task?

I've windowed them with BBCs. The 208 is pretty fragile, really.


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