Throttle valve adjustment

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supertruck

Unretired Old Fart stock car racer
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Vehicle is a 73 Sport 340 with the 200-4R transmission. Just finishing my restoration. Looking at adjusting the TV cable. Videos on YouTube all have slightly different methods. Some say extend the cable fully, open the linkage to WOT, and that's where the cable attaches. Others say to seat the adjuster, attach the cable, and go WOT one time and it will self adjust. Some show adding a small spring between the lock nut and the carb linkage. Others leave it out. Can any of you 200-4R guys who came ahead of me give me a definitive method that worked for you?
 
Vehicle is a 73 Sport 340 with the 200-4R transmission. Just finishing my restoration. Looking at adjusting the TV cable. Videos on YouTube all have slightly different methods. Some say extend the cable fully, open the linkage to WOT, and that's where the cable attaches. Others say to seat the adjuster, attach the cable, and go WOT one time and it will self adjust. Some show adding a small spring between the lock nut and the carb linkage. Others leave it out. Can any of you 200-4R guys who came ahead of me give me a definitive method that worked for you?
Does it have a factory GM tv cable? Those were adjusted at wide open throttle and push the button if I remember correctly. (that was over 30 years ago so I could be mistaken)
 
Vehicle is a 73 Sport 340 with the 200-4R transmission. Just finishing my restoration. Looking at adjusting the TV cable. Videos on YouTube all have slightly different methods. Some say extend the cable fully, open the linkage to WOT, and that's where the cable attaches. Others say to seat the adjuster, attach the cable, and go WOT one time and it will self adjust. Some show adding a small spring between the lock nut and the carb linkage. Others leave it out. Can any of you 200-4R guys who came ahead of me give me a definitive method that worked for you?
Maybe I'm not picturing this right, but if you extend the TV cable fully, open the throttle to WOT and attach the cable there, how could the throttle be able to return to idle?
I would get an actual GM service manual and use the factory method as best I could. YouTube is nice, but it's just like the rest of the Internet: Believe & Use at your own risk.
 
The idea is that as the throttle opens, the line pressure in the transmission increases. The TV cable does that - at WOT, the cable should be fully extended, which puts maximum pressure in the trans. When the carb returns to idle, the cable retracts and pressure is reduced. If it's not adjusted correctly, pressure can be too low and you'll burn the clutches up in a hurry. The issue is that some instructions say to open to WOT, fully extend the cable, and attach the plastic detent at that point, locking it in place with the cable nut. Others say to leave the carb at idle position, make sure the cable adjusting sleeve is fully seated, and attach the detent and lock it in place without extending it. Then, open the throttle to WOT one time, and the adjustment sleeve will automatically extend out to the proper position. Every set of instructions is slightly different. Since I know next to nothing about automatics, I want to get it right.
 
I don't care which instructions you follow, you're still going to have to play with it to get it right.
I realize that. I know you want the 1-2 shift to be between 15-20 MPH. Soft shifts too close together are what burn up the clutches. Lengthen or shorten the cable depending on whether you want harder or softer shifts and the MPH where the shift occurs. I only wanted to hear from some of the 200-4R guys on here on how they did it. But thanks for your input.
 
Butum, is the ratio right?
Do you mean the ratio at the carb linkage? If so. Yes. I have the pieces that bolt to the linkage to make sure the TV cable pulls the same as the throttle cable.
 
What I mean is this;
If the ratio is right, then you can set the cable per the FSM, and then the shifting will vary properly as to timing and intensity.
But if the ratio is wrong, you may be able to set it such that it is right at a particular load and rpm, but the further off-center you go, the timing and/or intensity becomes worse; and you end up chasing the adjustment around and around and around; see post #5.
And if the governor is wrong, you'll never get it to "work properly".

Every trans I have worked on has three principle pressures that have to be balanced, to either work together at times or to work against eachother at other times. Throttle pressure is just one of those. Additionally there is line pressure and governor pressure. There are others as well.
Line pressure is the primary pressure. It protects the vitals at modest throttle settings, and sets the tone for the shifts.
Governor pressure comes along and tries to command a shift in direct relation to the speed of the vehicle.
But throttle pressure delays the shift, by command of your right foot, and simultaneously affects the intensity of the shift, a by-product of increasing pressure to the clutches.
If you find that your right foot is in an awkward position at the time of an upshift, it is probably because the governor is out of sync. When you get it right, you will be able to command Part-Throttle shifts with your gas pedal, and she will be a joy to drive.
If you find that the shifts are not timed well between eachother, that is a pressure issue at the valve. For instance, if at a particular Part Throttle setting, the 2-3 shift seems to be too early or too late, as compared to what the 1-2 was, at about the same setting, then the cure for that is in the individual springing of the shift-command valves. I find that to be horribly annoying.
In the TorqueFlites, it seems to me that the 2-3 is often too early, and with the wrong governor, the trans will sometimes go from first, almost straight to third, unless I increase the throttle opening right after the 1-2 shift. That is nuts, and I can't take it, so off comes the VB.
After those are synced, I fix the governor, so the throttle pressure works the way I want it to at PT.
I don't care much about WOT shifts because that, to me, is what the manual shifter is for. And in my car, it spends maybe 90/95% of it's life at PT, NOT WOT, so I concentrate on making it fun to drive.
So, to recap; you have TWO or even THREE ratios;
1) the sync between the roadspeed and governor pressure, which is governed by the rear gear ratio and tire size, and
2) the sync between the Throttle Pressure and all others, which is governed by the distance the cable moves, which is governed by the distance between it's anchor and the center of the throttleshaft, and cable-slack. and
3) the sync between the shifts, governed by the individual shift-springs.
 
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I've rebuilt the 2004R and installed upgrades and shift kits. Others already posted how to set it initially, so there was no purpose for me to repeat their input. Personally, I resent any discussion of a non-mopar transmission on this site anyway. Next they'll be talking about 327's in the engine forum.
 
I've rebuilt the 2004R and installed upgrades and shift kits. Others already posted how to set it initially, so there was no purpose for me to repeat their input. Personally, I resent any discussion of a non-mopar transmission on this site anyway. Next they'll be talking about 327's in the engine forum.

That's a .060" over 318, right?
 
The idea is that as the throttle opens, the line pressure in the transmission increases. The TV cable does that - at WOT, the cable should be fully extended, which puts maximum pressure in the trans. When the carb returns to idle, the cable retracts and pressure is reduced. If it's not adjusted correctly, pressure can be too low and you'll burn the clutches up in a hurry. The issue is that some instructions say to open to WOT, fully extend the cable, and attach the plastic detent at that point, locking it in place with the cable nut. Others say to leave the carb at idle position, make sure the cable adjusting sleeve is fully seated, and attach the detent and lock it in place without extending it. Then, open the throttle to WOT one time, and the adjustment sleeve will automatically extend out to the proper position. Every set of instructions is slightly different. Since I know next to nothing about automatics, I want to get it right.
Supertruck is right. The outer cable needs to be fully retracted in the adjuster (pull the outer cable out of the adjuster as far as it will go) then attach the cable to the carb and with the tab released (locked) fully open the throttle. You should hear a "zip" sound as the it self adjusts. Then you can adjust the cable about one eighth inch at a time in or out to fine tune.This will only work if the brackets and pivot points are correct of course. Oh, and I sure hope you had that thing built or at least had a valve body kit installed. They weren't the toughest trans GM made. I did not like to see one come into the shop lol.
 
Thanks, Wally-T. Thats what I was looking for, the cable to self adjust as a starting point. And yes, the trans was rebuilt to be pretty stout.
 
So

So why then didn’t u ask the trans builder? U have been told a few times already how to adjust it. Kim

Well you know......horse, water, lead.....all that.
 
Thanks for the smart *** responses above. My original question was about which method to use. I've seen 3 separate "do it this way" videos and descriptions. And the transmission builder has retired and moved out of state. Sorry if I only gave the so-called experts some troll fodder.
 
Thanks for the smart *** responses above. My original question was about which method to use. I've seen 3 separate "do it this way" videos and descriptions. And the transmission builder has retired and moved out of state. Sorry if I only gave the so-called experts some troll fodder.

If you weren't being an askhole, you'd see through the smartass remarks and actually see everyone was trying to help. Was. You got the right answer the very first time and were too hard headed to see it. WTF would you come here askin for advice, then go to other video sources and come back arguing their way against what you were told here? Stupidity?

Whether you choose to believe it or not, the method you were told here was correct, regardless of what TYPE linkage, cable, twigs or "whatever" your setup. Look in the mirror. There's your problem right there.
 
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