350 vortec swap into OBS

[doo_hicky]

Hi all.

I'm lookint to swap a 1998 350 vortec into a 1988 350 TBI 4sp FS, but with 1 big possible issue.

1. I'm doing a SAS and going with a NP205 transfer case and from what I have read there will be an issue with the VSS, is this correct? What can be done?

I will have the complete motor,cpu, and harness.

Thanks for the help

mike

[Wtfan18]

lol dont be surprised when this post gets taken over with people encouraging a GENIII swap haha. they did it to me but im so damn glad!!!

[NITROUS]

First off yes, you can make it work..........Drop an LSX motor and tranny in. LOL J/K You'll need to purchased a 40-tooth reluctor ring for a 1991 NP205 and mount it on the output shaft of the transfer case. Then you'll need to either weld in the old speedometer hole in the case or make a bushing that can be shrunk into the hole with the threads machined or tapped in it for the new VSS. The housing is cast iron so you better be a good welder and preheat the case prior to welding. You'll need to make sure the new VSS is oriented exactly perpendicular to the output shaft and reluctor ring to get a good signal.

[doo_hicky]

Ok, so it sounds like I will be able to do this. I have access to machines at work that would be able to make a bushing, or I could also weld the case(I know how to weld).

I'm going to have to plead ignorance here, so please be patient. Where does the speedo mount now(transmission, or transfer case?

Ok, I think I got it. The old speedo hole in the np205 will either need to be welded closed and then machined, OR a bushing made to adapt the VSS to the that case, right?(it's early, not enough coffee in me yet)


Option 2 would to locate a 91 NP205.

Option 3 would be delete the fuel injection and go carb.

I am on a very tight budget.

Since I have an old(73-87) NP205 case I could try the bushing/weld method. Does it matter what year the transfer case is?

I may be able to locate a a newer transfer case, but it'll probably not be cheap.

Option 3 would also cost me, but it would probably be less headaches, does this all sound about right?

Thanks, I'm sure that I'm gonna have more questions concerning this.

mike

[RedHeartbeat]

why not just leave to stock speedometer setup in there and buy a digital converter box?

[doo_hicky]

Did not know that that was an option.

What kind of $$$$ we talkin?

What exactly does the VSS do?

Thanks

mike

[RedHeartbeat]

Controls when to shift, rear wheel ABS if you have it and speedometer if you install an electronic gauge. some reference items Speedometer 8K Pulse Generator

[doo_hicky]

Ok, but with my sm465 4sp manual a VSS would not be necessary, what would the drawbacks be if any? Can it be disconnected?

The adapters are something that I may opt to go with.

I'm sure that the speedo in my 88 is electronic, but I'll have to check for sure. There is no ABS on my truck.

Thanks again

mike

[NITROUS]

Life would be much easier with the cable like Greg is saying.

[doo_hicky]

Yes

Those adapters look like the ticket.

My buddy is making an S10 blazer with 1 ton axles and he is interested in those adapters also.

It sounds like this swap may be fairly easy, it is not set in stone yet, been researching if/how easy it would be to do with little or no modifications.

mike