NV4500: what to do?

[whateverpratt]

Hey all,
I picked up an nv4500 yesterday for cheap at a yard, and I'm putting it in my '63 c10 (has an sm420 at present). I am not going to use a hydraulic clutch, and I am not going to spend $400 on an aluminum aa bellhousing. I figure I have a few options as to completing this on the cheap, and I wanted to get some feedback.

The tranny:
Turns out it is a '96 2wd gm tranny with a fixed yoke. I think the fixed yoke is cool since I plan to convert the truck to 4wd in the future and plan to use a divorced t-case setup, but everything else sucks for my purposes as far as nv4500's go (5.6" input shaft bearing retainer, the 5.XX granny, etc.).

Option 1:
Use a GM bellhousing (don't have one, did not come with the transmission), and modify it for use with a mechanical clutch. I don't see this as a very good option since I don't really want to go cutting up a bellhousing I don't have, but I'm open to the idea.

Option 2:
Use an SM465 bellhousing. The SM465 bellhousing has a 5.125" bore for the input bearing retainer. That will not work because my tranny has the 5.6" bearing retainer. To fix this, I have a few options, and I don't know if they will work, so if you have done any of these or have seen it done, please let me know before I screw something up.

Option 2A: Swap the input bearing retainer from an earlier nv4500 that is 5.125". I'm thinking this won't work because I imagine the bolt pattern on the case is different, and I won't be able to just swap the retainer (that would be too easy). However, I don't have an earlier case or retainer on hand, so I don't know. Surely someone can help me rule out this idea.

Option 2B: Get my input retainer turned down to 5.125" at a machine shop. I'm not sure if this will work. It looks like the retainer just might have enough meat on it to get it turned down .475", but I haven't pulled it off to measure it yet. Has anyone done this? Again, this is probably too easy for it to work.

Option 2C: Have the SM465 bellhousing bored to 5.6". I'm visiting some yards today to see if I can look at one to see if it has enough meat to bore out. If it looks like it will work, would you guys use an aluminum or cast bell?
Cast is my default (I like the early years with the ears that have mounts like the SM420 bells), but I didn't know if for some reason it might be weaker than the aluminum after being bored. I could theoretically bore out the sm420 bell, but I don't know if the process would remove too much material. However, I need a sm465 bell to look at because they might be the same as far as webbing and thickness go.

If I can get the bore issue resolved by swapping the retainer, turning down the retainer, or boring the bellhousing, I'll just drill the NV4500 case for the saginaw bolt pattern and bolt that sucker up. Again, if anyone on here has actually drilled the NV4500 case to mount up to an SM465 bellhousing, I'd love to see pics, but I'm assuming no one has done it with a '96 and up since the few posts mentioning it that I have seen have used '93-'95 trannies.

Option 3: Make an adapter plate. If Option 2 doesn't come through for me, I can't think of another way to bolt a bellhousing up to the tranny without an adapter plate. However, my limited research has led me to believe that the stock GM unput shaft length is the same as an SM465, so if that turns out to be true, I will need a longer input shaft to make an adapter plate work. Luckily, the Dodge input shaft is longer than the GM, but I'm not sure how long because I have seen some places say .75" and some say 1" (can anyone clarify that for me?). Will a Dodge input shaft (1.125" 10 spline from a gas trans, not the 1.25" diesel) swap in to my '96 GM case? I think it will, but I'd like to know what you guys think. If it will swap, I could just swap the unput shafts, take some plate to a machine shop, and get some holes drilled.

That's my train of thought. Let me know what I've missed and what you think.

[1963c-10]

I don't have any experience with the NV4500, but I just did a hydraulic conversion for my big block build using a cast iron bellhousing. I think you have enough meat on the cast iron bellhousing to have a machine shop take out what you need to make the input you have work. I don't know the compatability of the trans to the bellhousing, so no help there. It will be close to the clutch fork pivot ball, but the only way to know will be to look at your bellhousing and take 1/4" off which will give you the 1/2" you need. I used a Novak clutch conversion and they are affordable. Gets rid of all the mechanical clutch linkage also. (I know you don't want hydraulic, but check out my build if your interested in what I did with the cast iron bellhousing and the Novak kit).

[Captainfab]

In my opinion any of your options above are more work than just getting the correct bellhousing and converting to a hydraulic clutch. I do sell a kit to convert to power brakes and a hydraulic clutch. With the kit I sell you could have power brakes and a hydro clutch in just a few hours.

I might be wrong, but I'm thinking the '96 NV4500 had the hydraulic throw out bearing.

[padresag]

the capt is right on. by the time you have a b/housing machined and find the right input shaft if there is. if it was so simple it would have been done by now
ron

[argonaut]

Unfortunately the AA bellhousing is your best bet.

[whateverpratt]

At this point I'm leaning towards option 3. The adapter plate should be super simple. Take some 1" plate, index the center to 5.6", drill 8 holes, counter sink the top two that bolt to the bellhousing, and tap the other 6. If the 1 1/8" Dodge shaft swaps in seamlessly, the only other thing I'll need to do is bore out a stock pilot bearing to fit the .75" diameter Dodge pilot, or turn down the Dodge shaft to .59". I think I have seen someone on here do something similar, or maybe they were on stovebolt.

[whateverpratt]

Well, I got that transmission in there. Here's the link to my post
http://67-72chevytrucks.com/vboard/s...=1#post6488778

[61K10]

whatever--nice job on a budget! glad there is someone out-there still making things work without throwing $$$$ about. sure it would be easier, but not everybody has the cash. as i said GOOD JOB!