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Discussion Starter · #1 ·
Does my 1980 with a TH350 have a lock up on the transmission? I'm asking this because I am getting a torque converter and that is one of the questions when choosing a torque converter.

I will still be changing it over to a 700r4. Just not not at the moment.
 

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I believe the 1980 did get a TCC ..[Torque Converter Clutch or lock-up converter] .. my 81 surely had it with the TH350 it came with ....are you having problems with yours or do you just want higher stall ? don t go over 2800 or you may have overheating issues in town driving
 

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Discussion Starter · #3 ·
I believe the 1980 did get a TCC ..[Torque Converter Clutch or lock-up converter] .. my 81 surely had it with the TH350 it came with ....are you having problems with yours or do you just want higher stall ? don t go over 2800 or you may have overheating issues in town driving
Now that my engine has 427 foot pounds of torque and 385 hp, I need a new torque converter. Based off my cam specs, looks like a 2000 torque will be about right.
 

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you could control the lock-up with that, but I m pretty sure the 80 used a vacuum operated switch on the manifold to operate it and a brake pedal switch to disengage on braking ........ anybody got an 80 w/TCC that can jump in???...my 81 originally used the ECM for TCC control, but 80 didn t have one
 

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So what do I look for to ensure that I do have the lock up?

Is this what I am looking for on my car/transmission? http://www.jegs.com/i/B&M/130/70244/10002/-1

If you had a locking torque converter there will be a wire entering the transmission case on the left side above and behind the shift lever. It seems like I have read the 80's and later all had locking torque converters.
 

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Discussion Starter · #8 ·
If you had a locking torque converter there will be a wire entering the transmission case on the left side above and behind the shift lever. It seems like I have read the 80's and later all had locking torque converters.
Thank you Steve. That was very helpful. I believe I see what you are talking about.
 

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Discussion Starter · #9 ·
I got a replacement TH350 at a great price. I just now figured out that the replacement transmission came out of a 78. A 78 what? I have no idea but it came out of a 78 and it does not have a spot for the lock up. DOH!!!! :doh: mutter mutter!:banghead: :mad5:
 

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The 1980 does have the lock-up converter and a toggle switch can be put on a wire that goes from the brake peddle switch for the brake lights under the dash. With the switch "off" the tcc cannot lock-up. With the switch "on" everything works as normal. I do not remember what color the wire was on the 1980 but will look through my notes... will get back once found.
Rick
 

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I got a replacement TH350 at a great price. I just now figured out that the replacement transmission came out of a 78. A 78 what? I have no idea but it came out of a 78 and it does not have a spot for the lock up. DOH!!!! :doh: mutter mutter!:banghead: :mad5:

Locking converters were just the first step of eliminating the rpm loss between the input and output shafts but became absolutely necessary when the TH700R4's came out because torque converters have so much slippage at low rpms.

As the TH350's operate at speeds so much higher their torque converters are about 95% efficient at cruising speeds. So it's no big deal your replacement TH350 isn't able to run one.
 

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I got a replacement TH350 at a great price. I just now figured out that the replacement transmission came out of a 78. A 78 what? I have no idea but it came out of a 78 and it does not have a spot for the lock up. DOH!!!! :doh: mutter mutter!:banghead: :mad5:
then you have no worry..if its 78 .its not a lock-up.. just get the converter to go with that trans ,at whatever stall you want.. ..I would suggest you add an auxillary trans fluid cooler...cheap insurance for long trans life
 

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Discussion Starter · #13 ·
then you have no worry..if its 78 .its not a lock-up.. just get the converter to go with that trans ,at whatever stall you want.. ..I would suggest you add an auxillary trans fluid cooler...cheap insurance for long trans life
At the risk of sounding really stupid, you said a "converter and a stall. What converter?
 

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At the risk of sounding really stupid, you said a "converter and a stall. What converter?
sorry if I confused you......it is a "Torque Converter"... Stall simply refers to the rpm of the torque converter where it "stalls" or stops slipping under power ....a stock torque converter stalls around 1350rpm... you want a torque converter with a 2000 or 2500 rpm stall speed to help your car launch better
 

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Discussion Starter · #15 ·
Okay folks, change gears. (Pun intended) I'm no longer going to build my 700r4. I will purchase one. What I need are some recommendations on where to buy. My specs are this: 427 foot lbs of torque, 385 hp, Edlebrock (#7102) cam. I may get a slightly larger cam later on. With that, a recommendation on a torque converter. Sorry if I'm frustrating anyone. No one more is frustrated than I. I'll explain later. I'm on my phone.
 

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in that case, you have lots of options.. PATC, TCI, Summit, Jegs, Monster Trans, all have ready to go 700r4s in 2 or 3 power levels and choices of stalls to suit.. you need one capable of handling 450-500 HP to allow for future upgrades.. once you chose a trans and a Stall Speed,I would stay 2000 to 2500 ranges , then you will need the necessary items to convert from 350 to 700r4.. Toobroke and I are both very familiar with this and can guide you....Monster has th350 to th700r4 conversion packages, you get almost everything you need in it ... except for crossmsmber mods and driveshaft resizing..
 

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Discussion Starter · #17 ·
in that case, you have lots of options.. PATC, TCI, Summit, Jegs, Monster Trans, all have ready to go 700r4s in 2 or 3 power levels and choices of stalls to suit.. you need one capable of handling 450-500 HP to allow for future upgrades.. once you chose a trans and a Stall Speed,I would stay 2000 to 2500 ranges , then you will need the necessary items to convert from 350 to 700r4.. Toobroke and I are both very familiar with this and can guide you....Monster has th350 to th700r4 conversion packages, you get almost everything you need in it ... except for crossmsmber mods and driveshaft resizing..
Cool! Cool! Cool! I just looked at the Monster web site. I like what I see. Looks like the one for me is the one for about 2k since I all ready have 427 torque. So where do I order the crossmember from?
 

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Monster has them, so does Bow Tie Overdrives for less $$$ .. http://www.bowtieoverdrives.com/catalog/catalog_inc/viewitem.php?ITEMID=115 ...or if you have access to a torch and welding machine you can just modify yours .. the bracket w/the bolt holes for transmission mount needs to be relocated ..the 700r4 is longer than a th350 , also the pulley brkt for parkbrake cable needs to be moved to left about an inch....and your driveshaft will need to be shortened by about 3 inches.. any driveshaft shop can do that for $75-$100 ... we can walk you thru it as you go...and by the way, the first time you drop the hammer on it w/700r4 and a 2000rpm stall , installed, the big grin on your face, will be stuck for several hours
 
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