Turbo 400 question or two

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bobehud

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i picked up a 91' 4x4 Burban with an early 80's 1 ton running gear.

I don't appear to have any type of kickdown at all,the trans is a fresh rebuild the PO had done,i changed to gasket and filter and it was bright red and super clean so i tend to believe that.I was also told by NAPA where i picked up the filter kit it was an early 70's HD 400 turbo,never heard of an HD 400 turbo.

Will not having that kickdown cause any damage..?
 

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i picked up a 91' 4x4 Burban with an early 80's 1 ton running gear.

I don't appear to have any type of kickdown at all,the trans is a fresh rebuild the PO had done,i changed to gasket and filter and it was bright red and super clean so i tend to believe that.I was also told by NAPA where i picked up the filter kit it was an early 70's HD 400 turbo,never heard of an HD 400 turbo.

Will not having that kickdown cause any damage..?
I know the earlier th400 had a button under the accelerater pedal and a plug in on the side of the tranny for kick down or passing gear. Not sure about later 400s.
 

bobehud

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According to NAPA it is a 72'
 

HotRodPC

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You're fine without having the kickdown hooked up. It does not regulate pressue like the 700r4 TV cable does. The 400 uses an electric solenoid. You should see a spade on the driver side of the trans, just above the pan. Your throttle pedal bracketry probably has the provisions for the Th400 kickdown switch. Its not hard to wire in at all.
 

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So is this a 91 4x4 Half ton Burb? What Transfer case do you have? If its carbed and Th400, your computer has been totally removed huh??? Its all Old School then I presume?
 

crazy4offroad

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His intro thread states, D60 front, 14b ff rear, and np205 t-case, aka 1-ton running gear... :deal:
 

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His intro thread states, D60 front, 14b ff rear, and np205 t-case, aka 1-ton running gear... :deal:

Cool, he got all the good ****. I was just trying to figure out if he will gas pedal kickdown provisions for his 400. In 91, if it was a half ton OEM, he might not. Might have to pull the throttle bracket assembly out of an older unit. Piece of Cake to do.
 

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OK, I found my pics of he gas pedal Th400 kickdown switch. Here is where it mounts and what it looks like.

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J Knight

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My 82 never had a th400 but its got the tab off of the firewall to mount the switch next to the pedal. I wonder if I have the wires?
 

HotRodPC

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My 82 never had a th400 but its got the tab off of the firewall to mount the switch next to the pedal. I wonder if I have the wires?

Since it's its own harness not likely not to have it, if the truck wasn't OEM Th400. Its not a big harness though and you can eaisly make your own since its just spades to the connectors and nothing special. One wire gets power from the fuse block, the other wire goes to the pedal switch to the spade on the trans. It gets its ground from the inside the trans. So when you activate the switch, it sends power to the solenoid therefore activating kickdown.

So see, people complain about Electronics in transmisisons and actually they have been electronic in nature since 1964. In fact, 64 & 65 when there was such thing as Variable Pitch torque converters, there was 2 soloenoids in the Th400. 1 for kickdown, and 1 for the varibale pitch TC. So if you see Th400 with 2 spades on the side of it in the same location, its a Variable Pitch trans. Very rare these days. I do happen to have one and do intended to use it someday. I'll be a 1800 stall, then hit a toggle switch and it will then be a 2500 stall. My little rice burner sleeper secret !!! I'll crush them little slant fishhead bastards. :roflbow:
 

bobehud

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Ok try this again.Thanks guys now i feel much better.Hotrod thanks for the input and yes its a beast 454 Edelbrock Intake Barry Grant speed Demon Vac Sec electric choke ( which im having fun sorting out) Ceramic coated headers,dual exh
Going to let the kickdown project sit for now have other little projects i want done before winter settles in.
 

HotRodPC

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Ok try this again.Thanks guys now i feel much better.Hotrod thanks for the input and yes its a beast 454 Edelbrock Intake Barry Grant speed Demon Vac Sec electric choke ( which im having fun sorting out) Ceramic coated headers,dual exh
Going to let the kickdown project sit for now have other little projects i want done before winter settles in.

Sounds like about as close to a bulltet proof project as you can get Bob. You've got all the stronger and more durable components. I'm not real familiar with the Demon Carbs.
Yes, you can get by without the kickdown for awhile with a Th400. If you feel its shifting a bit early, you can adjust the vac modulator a bit tighter to delay the shift a bit. I would just at least check to make sure you have the right gas pedal bracketry. If you don't, be keeping your eye out of it and ask around. Many times guys around here have parts laying around, and sometimes just want to see them go to a good home and help a member out for the cost of shipping. In fact, I have a burnt cab that was Th400. The pedal is burnt, the mounting is probably burnt, but if you can get your pedal and adapt it to his bracket, if you need it, then I'll pull it next time I get to the truck out at my dads. That could be awhle too. And I'm not sure if the pedal come off etc. You may have it already anyway.
 

bobehud

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Thanks HR..
Barry Grant is based on a Holley design,loosely based.You hit the nail on the head i wanted bullet proof...when people ask me my mileage i asked them its a carbed 454 what do you think.I dont like car payments im in the automotive industry, so i figure a little more money on gas so i can drive something like my Burban is worth it__to me.
 

HotRodPC

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Thanks HR..
Barry Grant is based on a Holley design,loosely based.You hit the nail on the head i wanted bullet proof...when people ask me my mileage i asked them its a carbed 454 what do you think.I dont like car payments im in the automotive industry, so i figure a little more money on gas so i can drive something like my Burban is worth it__to me.

Yes, I am going thru it with my bro right now His ElCo was totaled. He can't find another on in decent shape for under $2500 in running condition. I told him get a $600-$800 running but ugly square. No paymens, cheap insurance, cheap and plentiful parts for updates, cheap parts when they break. Not the best in gas, but for what little he drives, all the cheap parts and ease of working on, you can hardly beat a square. He is not auto savy at all but wants to work on his own stuff, so I told him he needs to stay away from computer controlled or fuel injection. We'll see if he listens. For the cash you save in expenses, you can afford to pay a little more at the pump. I drive my squares, and I go on a trip, I rent a car. The money I save in fuel pays for the car rental, and if it breaks down on the road, they come get me and its their problem. It just makes sense to me in my financial state right now. Even when things do get better, if I do get a newer vehicle again, I'll still keep my squares for back up and toys.
 
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bobehud

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Yeah HR love my inlaws but they MUST have a new car..been married to their daughter for 28+ years and they have always made payments.
When the stock market crashed and my dad in laws construction company rolled up the sidewalks those payments are killing them.I told them the same thing older,common = cheap.

i got some pics up somewhere..
 

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