700r4 install begins.
Thread Starter
Melting Slicks
Joined: Mar 2006
Posts: 2,465
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From: Orange Park Fl
I adjusted the brakes and now it seems to shift properly, but the TCC is still not locking up, I'll get that fixed one way or another tomorrow. Unfortunately, my headers chose now to fry another set of plug wires. I bought a set of the Accel shorty plugs today, even though I'm not crazy about Accel stuff, I'm just tired of burning wires. God bless, Sensei
Advanced
Joined: Oct 2001
Posts: 65
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From: Moerstraten NL
Hello Sensei,
Your TCC should lock up in 3rd but not in 4th. In the 81 wiring harness the 4th gear lock up wire already is there but its grounded at some point and not connected to 1 terminal on the ecm. I hope it helps
Greetings Peter.
Your TCC should lock up in 3rd but not in 4th. In the 81 wiring harness the 4th gear lock up wire already is there but its grounded at some point and not connected to 1 terminal on the ecm. I hope it helps
Greetings Peter.
Drifting
Joined: Oct 2004
Posts: 1,496
Likes: 1
From: Lafayette Louisiana
Race Director
Joined: Sep 2004
Posts: 11,874
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From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
why would it lock up in third but not in fourth?
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Joined: Oct 2001
Posts: 65
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From: Moerstraten NL
why would it lock up in third but not in fourth?
The lock up for fourth is a wire from the ecm that goes into the transmission and grounds in the transmission. So by a different cable then the first two the ecm powers this cable to let the 4th gear lock up kick in.
This also is why a 350 lockup only uses 2 wires and a 700R4 3 wires. The 81 vette has a TCC connector with 3 wires, but when you check for a good connection between the tcc connector and the ecm you'll see the 4th gear cable is grounded somewhere. In a 82 vette the same wire leads to 1 terminal connection on the ecm.
Groeten Peter.
Thread Starter
Melting Slicks
Joined: Mar 2006
Posts: 2,465
Likes: 0
From: Orange Park Fl
Okay, I think I'm finished. It turns out my converter IS locking up in 4th, but the brake pedal does not unlock it. I'll take care of that one when I get a chance. I'll just try not to lock up the brakes in 4th gear in the mean time. Otherwise I believe I'm finished. I have the TV adjustment on the carb all the way forward, which I believe makes it shift a bit later on normal acceleration. I may play with this adjustment when I find that allen wrench I had to cut off to install the TV connector. The whole thing took just over a week. Big thanks to my awesome wife who took care of our bussiness by herself while I worked in the driveway all day and thanks to everyone here on the forum who chimed in on this thread 
. I hope my experience as related here may help the next person with their install. God bless, Sensei
. I hope my experience as related here may help the next person with their install. God bless, Sensei
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Joined: Oct 2001
Posts: 65
Likes: 0
From: Moerstraten NL
If the wiring harness inside the 700R4 is already altered it should lock up in 4th but not in 3rd. If it does.. I'm very curious what the wiring harness looks like. I got a wiring harness from bowtie but the (as you discribe) lock up in 4th and ground inside the transmission. So I'm curious if it locks up with or without the ecm
Groeten Peter.
Groeten Peter.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
OK, for ten years now and just a few months recently, I have had a 700 and a 200 4r tranny in my '72 vette here....
I feel that anyone reading/understanding a wiring diagram can figger out how the things work on lockup....ie...identical function....
only mechanical thing to know is that lockup occurs only under acceleration....so IF the electricals demand lockup, you have to be under forward power/acceleration....for it to actually happen....
but once it does occurr, it will stay locked, untill the electricals say to unlock, ie..the circuit is broken to the solenoid...de energizing it....
Lockup can occur in ANY gear, allthough I m NOT SURE about FIRST gear.....both of them would easily lock up in 2nd gear/up.....
I have a switch on my console that decides wether manual lockup or computer controlled....I can make the engine lug down to 1000 rpm's in lockup...like a stick in 4th gear....and the tranny will act like a stickshift if I want it to....
I feel that anyone reading/understanding a wiring diagram can figger out how the things work on lockup....ie...identical function....
only mechanical thing to know is that lockup occurs only under acceleration....so IF the electricals demand lockup, you have to be under forward power/acceleration....for it to actually happen....
but once it does occurr, it will stay locked, untill the electricals say to unlock, ie..the circuit is broken to the solenoid...de energizing it....
Lockup can occur in ANY gear, allthough I m NOT SURE about FIRST gear.....both of them would easily lock up in 2nd gear/up.....
I have a switch on my console that decides wether manual lockup or computer controlled....I can make the engine lug down to 1000 rpm's in lockup...like a stick in 4th gear....and the tranny will act like a stickshift if I want it to....
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