Th400 kickdown issues

[HotRodPC]

Thanks for the info boys.
Shifting under normal conditions is perfect. It’s only on WOT where I think it could hold gears a little longer.

It is a fully rebuilt box with a 2500 stall. I believe it was out of a Chev truck of some sort. It is apparently longer than a normal one.
Car is a 78 Holden but it does have the kickdown switch mounted on the throttle and it does have power.

OK, now I know what we're talking about. So yes the switch can be on the carb for certain like GM cars did in the 60's. So you need to test that switch at the carb. It's either ON or OFF, so it's either GOOD or BAD. No inbetween. You can easily test that with a test light. Next, test to see if you have 12 volts going to that power side of that switch. If you have the 12 volts and the switch is good, then you should have 12 volts at the plug on the side of the transmission unless there is a damaged or grounded out wire.

Assuming you have 12 volts and the switch is good. There's is only 3 others things it can be and all 3 will require the pan coming off. 1, the plastic plug on the side of the case has broke the spade that runs through the plastic plug. 2, The kickdown solenoid wire has come disconnected from the internal spade of the plastic plug, 3, The solenoid itself has gone bad and needs replaced. Very easy to change if it needs it.

 

[Honky Kong jr]

Up shift is controlled by vacuum threw the modulator. Is your engine creating enough vacuum to do this? They make adjustable modulators to fine tune shift points. Also what, if any , shift kit is in your trans? That may have a lot to do with you holding gears issue.

 

[74 Shortbed]

If it came out of a heavy truck or setup for heavy loads, the shift points are going to be way higher than what's needed in a lightweight car, sounds to me all it needs is a little tuning..

 

[1987_chevy_]

Up shift is controlled by vacuum threw the modulator. Is your engine creating enough vacuum to do this? They make adjustable modulators to fine tune shift points. Also what, if any , shift kit is in your trans? That may have a lot to do with you holding gears issue.

Yes it upshifts fine

 

[1987_chevy_]

Has to be a "jerry rig"... He's running this carburetor on a 383.. https://www.holley.com/products/fuel_systems/carburetors/quick_fuel/hot_rod_series/parts/HR-650

Lmao Dude it's an aftermarket kickdown switch, so it is not jerry rigged! Not everyone has access to OEM parts! It's meant to sit on the carb like it does And second off, that's not the fricken carb I'm running! There is a difference between quickfuel and Holley! Go on google and type in quickfuel ( believe it or not the 650cfm hotrod series carb will pop up, if you open your eyes)

 

[RustyPile]

Lmao Dude it's an aftermarket kickdown switch, so it is not jerry rigged! Not everyone has access to OEM parts! It's meant to sit on the carb like it does And second off, that's not the fricken carb I'm running! There is a difference between quickfuel and Holley! Go on google and type in quickfuel ( believe it or not the 650cfm hotrod series carb will pop up, if you open your eyes)

First off, I'm not a "dude", you snotty nosed little brat.. That link came from your other "dyno tuned carb" thread, where you were asked by several to post a picture your carb, WHICH YOU NEVER DID.. So I, along with several others don't know which ******* carburetor you actually have..

TH400s came out in the '60s, and originally the kickdown switch was located on the Quadrajet carburetor.. Later, it was moved to the throttle pedal bracket.. So if your carburetor isn't a Quadrajet and the kickdown switch is located on the carburetor, then yes, Mr. dyno tuned carb man, your switch is jerry rigged...

You have your nerve coming on here asking, in one breath, for advice from a group of guys that actually worked on these old trucks long before these trucks ever reached "classic" status, and in the next breath, start name calling..

Listen punk, I was working on these trucks before your DADDY was born. And I was building race cars and race engines when your grandfather was a young man.. There's NOTHING you can tell me about any of this. But it'll be a cold day in hell before you get ANYTHING from me again.....

LMAO that in your bong and smoke it....

 

[Honky Kong jr]

You must be registered for see images attach

To soon?

 

[HotRodPC]

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To soon?

Nawww, That ain't gonna happen. Appears there's a disagreement of words between just those 2 so leave it at that.

 

[1987_chevy_]

First off, I'm not a "dude", you snotty nosed little brat.. That link came from your other "dyno tuned carb" thread, where you were asked by several to post a picture your carb, WHICH YOU NEVER DID.. So I, along with several others don't know which ******* carburetor you actually have..

TH400s came out in the '60s, and originally the kickdown switch was located on the Quadrajet carburetor.. Later, it was moved to the throttle pedal bracket.. So if your carburetor isn't a Quadrajet and the kickdown switch is located on the carburetor, then yes, Mr. dyno tuned carb man, your switch is jerry rigged...

You have your nerve coming on here asking, in one breath, for advice from a group of guys that actually worked on these old trucks long before these trucks ever reached "classic" status, and in the next breath, start name calling..

Listen punk, I was working on these trucks before your DADDY was born. And I was building race cars and race engines when your grandfather was a young man.. There's NOTHING you can tell me about any of this. But it'll be a cold day in hell before you get ANYTHING from me again.....

LMAO that in your bong and smoke it....

Lmfao, dude I can call you what I want! Just because it's not factory does not mean it's jerry rigged! I don't need to post a picture of the carb all you have to do is go online and look it up! I fucken told everyone is not a Holley. And your ******* post a link to a Holley carb Idc how long you have been working on vehicles, you sure in the hell don't know everything! So why don't you go smoke your bong, because I'm not a fucken retard that smokes weed!

 

[CSFJ]

Lmfao, dude I can call you what I want! Just because it's not factory does not mean it's jerry rigged! I don't need to post a picture of the carb all you have to do is go online and look it up! I fucken told everyone is not a Holley. And your ******* post a link to a Holley carb Idc how long you have been working on vehicles, you sure in the hell don't know everything! So why don't you go smoke your bong, because I'm not a fucken retard that smokes weed!

But, you have no qualms about getting on a forum asking for help and not providing all the information requested. Then, you want to act like you have all the answers and be disrespectful. You're right, a person could google a random picture of whatever carb you claim to have, but that wouldn't show the people who could help you exactly what YOUR carb set-up looks like, to help sort your problem. But since you seem to have all the answers, keep us posted on how it turns out.

 

[HotRodPC]

Lmfao, dude I can call you what I want! Just because it's not factory does not mean it's jerry rigged! I don't need to post a picture of the carb all you have to do is go online and look it up! I fucken told everyone is not a Holley. And your ******* post a link to a Holley carb Idc how long you have been working on vehicles, you sure in the hell don't know everything! So why don't you go smoke your bong, because I'm not a fucken retard that smokes weed!

You've got some things to learn and I'll leave it at that. If you're not happy with the help you've gotten here, perhaps you might try www.pirate4x4.com. Them guys know their **** over there.

We don't get into calling people stupid and ********* here and certainly don't intentionally offend anyone unless it's in good fun but this obviously isn't in good fun. I know many people who smoke weed. You ever seen a person suffer to death of cancer or have cluster seizures? I'd hate to see what happened to you if you got near their families and called them fucken retarded. At any rate, try arguing as an adult rather than name calling and offending people, especially those who are not even involved in your disagreement.

 

[da_raabi]

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In other news, someone was asking about not being able to downshift to first at high speed. I believe that is a built-in safety feature in the TH400 valve body. If you really want to be able to do that, and possibly blow up your engine in SPECTACULAR fashion you can install a Transgo 400-1&2 shift kit. It will allow you to take control and downshift at any time. Otherwise I don't think the TH400 would let you downshift to first at that speed.

 

[Honky Kong jr]

When is it my turn?????? Soon?

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[CSFJ]

When is it my turn?????? Soon?

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For some reason No one wants to start **** with the guy who has Super Sarcastic Man under his avatar, lol.

 

[Honky Kong jr]

For some reason No one wants to start **** with the guy who has Super Sarcastic Man under his avatar, lol.

I like to play......and I’m good at it too.lol