Flywheel differences

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SquareRoot

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Hey Franken-, what did you accomplish on the conversion this weekend?

I spent most of my time cleaning up wiring, painting the firewall and swapping the hydro boost unit. Slow going but it's cleaning up nicely. Also got the wiper unit apart, cleaned up and basically rebuilt while I had it off. And the clutch master cylinder in.
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Frankenchevy

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Hey Franken-, what did you accomplish on the conversion this weekend?

I spent most of my time cleaning up wiring, painting the firewall and swapping the hydro boost unit. Slow going but it's cleaning up nicely. Also got the wiper unit apart, cleaned up and basically rebuilt while I had it off. And the clutch master cylinder in.
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I got the interior stripped, steering column out, pedals out, re-wrapped the interior harness, pulled the th400, pulled the sniper and sold it.

Going to reinstall the interior harness and work the pro-flo4 harness into the truck before moving forward.
 

SquareRoot

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@Franken,

How about a progress report...with pics?

I spent yesterday finishing up the wiring harness. I needed to remove unused wires, reroute and loom the circuits and map and document every circuit I have modified. This was a task as I have replaced the original gauges with Dakota Digital, yanked out all the OE cruise control, emissions crap, carb and choke crap and replaced the AC with Vintage Air and of course the Edelbrock EFI. Needless to say factory wiring diagrams don't help me much anymore. :superhack:
 

Frankenchevy

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@Franken,

How about a progress report...with pics?

I spent yesterday finishing up the wiring harness. I needed to remove unused wires, reroute and loom the circuits and map and document every circuit I have modified. This was a task as I have replaced the original gauges with Dakota Digital, yanked out all the OE cruise control, emissions crap, carb and choke crap and replaced the AC with Vintage Air and of course the Edelbrock EFI. Needless to say factory wiring diagrams don't help me much anymore. :superhack:
Well, I have three pedals now. That part is all done. Repainted and rebushed the pedal assembly and disassembled the steering column to clean it up. Not quite finished with how I’ll route the wiring. I might unwrap it all and use mesh loom instead.
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Frankenchevy

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@SquareRoot , well minor setback. I was cleaning up the 208 and found a split in the input oil seal. It’s not leaking any oil, but I don’t want to risk ATF getting into my new trans and smoking it. I need to either get it rebuilt, rebuild it myself or switch to a round pattern 205.

The only round pattern 205 readily available is probably an ORD unit.
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edit: scratch that, ORD only has figure 8 pattern 205
 
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SquareRoot

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That seal is easy enough to replace. Why replace/rebuild the t-case? I rebuilt mine, it's fairly easy, just time consuming. If you swap to a 205, you're gonna end up with driveshaft mods.
 

Frankenchevy

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That seal is easy enough to replace. Why replace/rebuild the t-case? I rebuilt mine, it's fairly easy, just time consuming. If you swap to a 205, you're gonna end up with driveshaft mods.
That’s just it, time...

What rebuild kit did you use?

The upside to a 205 non slip yoke is I could run a drive line brake.
 

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I don't recall. Maybe a kit from Torque King.

Do you not have the cucv drum brakes anymore?
 

Frankenchevy

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I don't recall. Maybe a kit from Torque King.

Do you not have the cucv drum brakes anymore?
No, I have disc brakes off a 78 caddy eldorado. The parking brake is so-so.
 

Frankenchevy

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I’m leaning towards the USA standard gear kit for the 208. Seems to have all the goodies short a couple things for the front drive.
 

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Wow, very cool there are two guys doing almost the same thing with their trucks at the SAME TIME. Its great to be able to bounce your ideas and frustrations off each other. I found it very difficult to garner the information I needed to do my tranny swap. Couldn't find anyone that was doing what I did in recent years. Went to a Chevy dealer who also runs a speed shop for information about clutch compatibility and they said it couldn't be done. I did get some help from a custom clutch shop in New York. Once he helped me through that phase I had even more questions. After almost a year I now have the ruck running (able to move under its own power) but have some more fine tuning and adjustments to do. I have gotten pretty good at pulling that 250lb. tranny. I went total hydraulic with a concentric bearing. So if you guys need anyone else to bounce ideas and trouble shooting issues give me a shout, I'll help where I can.
By the way , my swap was an '03 ZF 6s 650 out of a 3500 Silverado bolted on to a '91 R3500 3+3 with a 454BB. The truck already had a SM465 tranny so I didn't have to add the clutch pedal assembly, but I did install the 03 clutch master cylinder and that was a total custom R & D project.

Good luck with your projects!
 

papstruck454

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Dale a……. I know this is an older post but I have a truck similar to yours and I’m very interested in swapping to a 5 speed something with overdrive. I was thinking nv4500 but zf6 may be just as good. I’m running sm465 behind 454 now and just want an overdrive for interstate travel. How you like your combination and please just tell me all about it. What’s the hardest part of the swap?
 

Frankenchevy

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Dale a……. I know this is an older post but I have a truck similar to yours and I’m very interested in swapping to a 5 speed something with overdrive. I was thinking nv4500 but zf6 may be just as good. I’m running sm465 behind 454 now and just want an overdrive for interstate travel. How you like your combination and please just tell me all about it. What’s the hardest part of the swap?
Are you planning to stick with mechanical clutch linkage or converting to hydraulic?

Also, it’ll alert @Dale A to your question if you quote him, as I’ve done to you here; or simply put the @ in front of a members name, like I’ve done to Dale A above. Just some stuff I had to figure out, not being social media savvy myself.

Good luck on the swap!
 

papstruck454

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Wow, very cool there are two guys doing almost the same thing with their trucks at the SAME TIME. Its great to be able to bounce your ideas and frustrations off each other. I found it very difficult to garner the information I needed to do my tranny swap. Couldn't find anyone that was doing what I did in recent years. Went to a Chevy dealer who also runs a speed shop for information about clutch compatibility and they said it couldn't be done. I did get some help from a custom clutch shop in New York. Once he helped me through that phase I had even more questions. After almost a year I now have the ruck running (able to move under its own power) but have some more fine tuning and adjustments to do. I have gotten pretty good at pulling that 250lb. tranny. I went total hydraulic with a concentric bearing. So if you guys need anyone else to bounce ideas and trouble shooting issues give me a shout, I'll help where I can.
By the way , my swap was an '03 ZF 6s 650 out of a 3500 Silverado bolted on to a '91 R3500 3+3 with a 454BB. The truck already had a SM465 tranny so I didn't have to add the clutch pedal assembly, but I did install the 03 clutch master cylinder and that was a total custom R & D project.

Good luck with your projects!
Dale I want to know more about your trans swap. Sounds like we have similar trucks except I’m sporting the sm465. It does great around town really but you know how they are. Slow, dump truck stuff and no overdrive. Mainly wanna pick up the range and mpg improvements with having an overdrive. How’s the zf6 fit up between the 454 and np205?
 

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