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budget 258 rebuild
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DaemonForce View Drop Down
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Originally posted by TheBirdman TheBirdman wrote:

...now if only my fluid coupling worked. Im putting an np229 or 242 on the dear santa list.

Viscous clutch?! I'm doing the NP229 conversion later. If you ever get the chance, go 242. Otherwise, I may get to documenting such an involved build before you.
Originally posted by Pdok Pdok wrote:

Too many variables, no telling where the throttle is. It's easier than that, though. Just add tension to the cable until it shifts where you want it. Shouldn't take much at all. It's always going to shift up at low throttle earlier anyway, it's the downshift that counts when you put your foot in it.

Pretty much this. The one and only thing I didn't like about the TF998 was the upshift behavior but if you're having downshift issues, just tension the cable until it feels correct. You don't want it downshifting while accelerating unless you're really putting your foot into it.
1971 Javelin SST
American 304 2v | FMX | AM20-3.31
1983 American Limited
Jeep 4(.7)L S-MPFI | 1982 NWC T-5M (4.03/.76) | Dana30IFS/35-2.72
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The throttle valve (TV) must always, always, always be fully depressed when the carburetor is wide open. That has to happen. The TV should also be fully released against its adjustable stop screw when the carburetor is fully closed. In other words, fully depressed on the TV must coincide with fully open on the carburetor and fully released on the TV should coincide with fully closed  on the carburetor.

Now I know what you are thinking. "I'll just adjust the TV stop screw so that it just barely contacts the TV with the throttle fully closed." NO!. That is not what the stop screw is for. It is there to adjust the hydraulic throttle pressure developed during closed throttle. It is the closed throttle baseline setting, like the idle speed screw on your carburetor. It seldom needs to be messed with. 

If you have adjusted your linkage so the TV is fully depressed at full throttle but the TV is not just barely touching the adjustment screw, then you needs to change the mechanical leverage in the linkage with a longer or shorter effective length on the TV bellcrank on the outside of the transmission, or where the other end of the linkage attaches to the carburetor. 

The TV system exists to exactly follow the movement of the throttle, that's it. The TV system is not intended as an adjustment for shift firmness or shift timing. Those tasks are handled by the line pressure and the governor pressure. I DO NOT advise messing with either the line pressure adjusting screw on the throttle body or messing with the governor unless you absolutely positively know what you are doing, have somebody around who does know what they are doing to guide you, or if you don't mind the high risk of literally blowing up your transmission by experimenting with fire. ....but line pressure and governor pressure are technically the right ways to adjust shift firmness and timing. That is how the engineers working for Chrysler did it. 

That all being said, adjusting the TV linkage tighter so that the TV is depressed more at any given throttle opening is a shortcut way to make shifts firmer and later. It's not the right way of doing it, but it's the way most people do it because not many people know how to literally reprogram the brain of a Torque Flite. Just remember that the TV must ALWAYS reach fully depressed at the same time the carburetor reaches wide open. You probably need a longer effective length bellcrank on the TV to accomplish this.
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The early shift at light throttle is intended for economy. It should shift a bit more aggressively at heavier throttle application. If it's not to your liking you can make small adjustments to the cable, but not much. Get a "towing" or "RV" shift kit for firmer and slower shifting.
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If memory serves, my tsm talks about adjusting shift that way. On mine, it only takes a couple millimeters to notice a change.
76 Grem X 258/904,4.0 head/MPFI, Comp X250H cam, Hughes springs, Clifford header, serpentine swap.
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Originally posted by FSJunkie FSJunkie wrote:



The throttle valve (TV) must always, always, always be fully depressed when the carburetor is wide open. That has to happen. The TV should also be fully released against its adjustable stop screw when the carburetor is fully closed. In other words, fully depressed on the TV must coincide with fully open on the carburetor and fully released on the TV should coincide with fully closed  on the carburetor.

Now I know what you are thinking. "I'll just adjust the TV stop screw so that it just barely contacts the TV with the throttle fully closed." NO!. That is not what the stop screw is for. It is there to adjust the hydraulic throttle pressure developed during closed throttle. It is the closed throttle baseline setting, like the idle speed screw on your carburetor. It seldom needs to be messed with. 

If you have adjusted your linkage so the TV is fully depressed at full throttle but the TV is not just barely touching the adjustment screw, then you needs to change the mechanical leverage in the linkage with a longer or shorter effective length on the TV bellcrank on the outside of the transmission, or where the other end of the linkage attaches to the carburetor. 

The TV system exists to exactly follow the movement of the throttle, that's it. The TV system is not intended as an adjustment for shift firmness or shift timing. Those tasks are handled by the line pressure and the governor pressure. I DO NOT advise messing with either the line pressure adjusting screw on the throttle body or messing with the governor unless you absolutely positively know what you are doing, have somebody around who does know what they are doing to guide you, or if you don't mind the high risk of literally blowing up your transmission by experimenting with fire. ....but line pressure and governor pressure are technically the right ways to adjust shift firmness and timing. That is how the engineers working for Chrysler did it. 

That all being said, adjusting the TV linkage tighter so that the TV is depressed more at any given throttle opening is a shortcut way to make shifts firmer and later. It's not the right way of doing it, but it's the way most people do it because not many people know how to literally reprogram the brain of a Torque Flite. Just remember that the TV must ALWAYS reach fully depressed at the same time the carburetor reaches wide open. You probably need a longer effective length bellcrank on the TV to accomplish this.


I agree. Right here. This is correct. Not doing it correctly is when you have problems.
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Originally posted by farna farna wrote:

The early shift at light throttle is intended for economy. It should shift a bit more aggressively at heavier throttle application. If it's not to your liking you can make small adjustments to the cable, but not much. Get a "towing" or "RV" shift kit for firmer and slower shifting.

If you want it to shift sooner, Don't mess with the Tv rod. Read what FSjunkie said. If you want lower shift points you change the springs in the governor.
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It only ended up being a little bit that it needed adjusted, but now its shifting at much more appropriate times. Before adding a little extra length to the tv linkage, it would go through all 3 gears before I even got through an intersection on a left turn. Perhaps its not the 100% kosher way of adjusting shift points, but it seems to me that its better to err a little on the side of too much tv pressure than not enough. With a car this old and worn, nothing is as precise as it was from the factory. That being said I will get someone to give me a hand and Ill check if they bottom out at full throttle at the same time.

Originally posted by farna farna wrote:

The early shift at light throttle is intended for economy. It should shift a bit more aggressively at heavier throttle application. If it's not to your liking you can make small adjustments to the cable, but not much. Get a "towing" or "RV" shift kit for firmer and slower shifting.

I did just install a TF-2 shift kit, but there is no way in heck that shifting that early is how it was intended to operate.

Originally posted by DaemonForce DaemonForce wrote:

Originally posted by TheBirdman TheBirdman wrote:

...now if only my fluid coupling worked. Im putting an np229 or 242 on the dear santa list.

Viscous clutch?! I'm doing the NP229 conversion later. If you ever get the chance, go 242. Otherwise, I may get to documenting such an involved build before you.

Yeah, the viscous clutch is hooped on this old bird. When I drained the ATF to change it, a good amount of silicone grease came out with it, and I have confirmed in the snow that if one rear wheel starts spinning, thats it, no front traction for you. I know that I potentially face the same issue with a second hand 229, but at least the 229 has a locked low range, so if I really needed front and rear traction to get out of a snowbank or something, I would have it. A 242 would be nice, but I like that aside from the speedo cable, the 229 is a direct bolt in swap. I guess it all comes down to which one I can find in a salvage yard once my annoyance at lack of traction outbalances my wallet.

Let me know if you end up swapping one in before me, Id be interested in your findings.

On an unrelated note, does anyone have a downloadable copy of an eagle owners manual? Id be interested to read up on a few features that I cant find information for on the internet.


Edited by TheBirdman - Dec/12/2017 at 10:11am
1983 Eagle Wagon
4.0 from 93 cherokee
AW4, NP242, and EFI from 99 cherokee
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Originally posted by TheBirdman TheBirdman wrote:

but at least the 229 has a locked low range, so if I really needed front and rear traction to get out of a snowbank or something, I would have it.

This is actually the entire reason that I looked into this in the first place. I was that guy that got stuck in a snow drift and couldn't move any tires because of extremely tall gearing and no low range. I may just end up dropping my gear ratios anyway but I don't look forward to it. There's too much wrong with running 2.72 gears on oversized tires. 3.08 would have given me the same issue. 3.31 would inch free and I proved it with the Javelin but I don't get that option in 4WD and that's on a 5L V8 with no low option. So I should probably look to a 3.08 set and add low.
Originally posted by TheBirdman TheBirdman wrote:

A 242 would be nice, but I like that aside from the speedo cable, the 229 is a direct bolt in swap. I guess it all comes down to which one I can find in a salvage yard once my annoyance at lack of traction outbalances my wallet.

1983-84 L6 G.Wagoneers and 1984-85 V6 Cherokees have them. I never considered the NP229 to be a bolt-in swap. In fact I'm looking at ripping mine apart for overhaul and reclocking it with parts from my NP129. Also, I need to do something with my speed sensor. I can tell that won't work with my 1996 electronics.
1971 Javelin SST
American 304 2v | FMX | AM20-3.31
1983 American Limited
Jeep 4(.7)L S-MPFI | 1982 NWC T-5M (4.03/.76) | Dana30IFS/35-2.72
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Originally posted by DaemonForce DaemonForce wrote:

Originally posted by TheBirdman TheBirdman wrote:

but at least the 229 has a locked low range, so if I really needed front and rear traction to get out of a snowbank or something, I would have it.

This is actually the entire reason that I looked into this in the first place. I was that guy that got stuck in a snow drift and couldn't move any tires because of extremely tall gearing and no low range. I may just end up dropping my gear ratios anyway but I don't look forward to it. There's too much wrong with running 2.72 gears on oversized tires. 3.08 would have given me the same issue. 3.31 would inch free and I proved it with the Javelin but I don't get that option in 4WD and that's on a 5L V8 with no low option. So I should probably look to a 3.08 set and add low.
Originally posted by TheBirdman TheBirdman wrote:

A 242 would be nice, but I like that aside from the speedo cable, the 229 is a direct bolt in swap. I guess it all comes down to which one I can find in a salvage yard once my annoyance at lack of traction outbalances my wallet.

1983-84 L6 G.Wagoneers and 1984-85 V6 Cherokees have them. I never considered the NP229 to be a bolt-in swap. In fact I'm looking at ripping mine apart for overhaul and reclocking it with parts from my NP129. Also, I need to do something with my speed sensor. I can tell that won't work with my 1996 electronics.

Weeeellllll, youre right in that a 229 isnt exactly bolt on, I was planning on swapping the rear case half of the 129 onto it as well. As far as controls though, it would be much easier to swap than a 242 because I could retain use of the vacuum shift, and cut a hole in the floor for the low range selector.
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I'm thinking of doing that with a linkage set I found on a late 70's Cherokee Chief. The NP229 uses the same old vacuum shift solenoids for 2WD/4WD modes and some exclusive control for HI/LO. It's been a few years since I've messed with it but if I remember right, those linkages go to the same track. So on top of an additional 40lbs, there needs to be a shift control that slips over the old shift bolt like a collar shifter. I need to check out some of the older Borg Warner units and how they handle the shift mechanism for this because I don't recall anything outside of a hard set mechanical Z-bar shifter in the V6 Cherokees. Swapping yolks is kind of nightmarish too. If anything, it would be easier to just fab up a bar link shifter under the driver seat rather than trying to duplicate the side by side console shift linkage that I was looking at when this car still had an automatic. Maybe it really is better this way.
1971 Javelin SST
American 304 2v | FMX | AM20-3.31
1983 American Limited
Jeep 4(.7)L S-MPFI | 1982 NWC T-5M (4.03/.76) | Dana30IFS/35-2.72
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