Will 81 computer work 200r4 transmission?
Thread Starter
8th Gear
Joined: Jul 2007
Posts: 8
Likes: 0
From: Marysville In
Will 81 computer work 200r4 transmission?
This forum has convinced me to stick with the original computer in my 81. Was just wonder if it could, handle the lockup function on a 200r4 converter too? I am also thinking of sticking with the original rearend gears too? Not looking to go drag racing just street rippin.
Safety Car
Joined: Dec 2005
Posts: 4,270
Likes: 20
From: Central Michigan
You may not need a custom chip. There only may be a difference in the lockup points, and if there is it might not be much. But it is something to look into before making the trans swap, especially if you plan on staying with the stock rear gears
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
It will work fine, the CCC doesn't know anything about what kind of tranny you have, all it does is tell the tranny it is ok to lock up any a particular time because some conditions have been met, like the coolant temp is up (temp sensor on the manifold)and you have on some speed (speed sensor on the speedo)
Safety Car
Joined: May 2001
Posts: 3,758
Likes: 3
From: Surrey
SIXFOOTER has it correct. You'll probably need to do a couple of simple wiring mods, but the CCC should handle it just fine. The wiring mods are just to cope with the different ways that lockup is done between the two trans types.
Th350c lockup has 12v on pin A of the trans connector & the computer connects the wire from pin D to ground (via the TCC/EGR relay) to complete the circuit through the TCC solenoid.
The Th200-4r I've got (from BTO) grounds the solenoid internally, so you'd need to modify the wiring so that the computer supplies 12v to pin A of the connector when it wants lockup in OD (& 12v to pin D if you want lockup in "3").
I did a wiring diagram for modifying mine which I can email if you PM me your email address (though it was done for the BTO unit, I haven't a clue if other units have the same internal wiring).
Th350c lockup has 12v on pin A of the trans connector & the computer connects the wire from pin D to ground (via the TCC/EGR relay) to complete the circuit through the TCC solenoid.
The Th200-4r I've got (from BTO) grounds the solenoid internally, so you'd need to modify the wiring so that the computer supplies 12v to pin A of the connector when it wants lockup in OD (& 12v to pin D if you want lockup in "3").
I did a wiring diagram for modifying mine which I can email if you PM me your email address (though it was done for the BTO unit, I haven't a clue if other units have the same internal wiring).
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Race Director
Joined: Jul 2004
Posts: 12,706
Likes: 329
From: Scottsdale Arizona
SIXFOOTER has it correct. You'll probably need to do a couple of simple wiring mods, but the CCC should handle it just fine. The wiring mods are just to cope with the different ways that lockup is done between the two trans types.
Th350c lockup has 12v on pin A of the trans connector & the computer connects the wire from pin D to ground (via the TCC/EGR relay) to complete the circuit through the TCC solenoid.
The Th200-4r I've got (from BTO) grounds the solenoid internally, so you'd need to modify the wiring so that the computer supplies 12v to pin A of the connector when it wants lockup in OD (& 12v to pin D if you want lockup in "3").
I did a wiring diagram for modifying mine which I can email if you PM me your email address (though it was done for the BTO unit, I haven't a clue if other units have the same internal wiring).
Th350c lockup has 12v on pin A of the trans connector & the computer connects the wire from pin D to ground (via the TCC/EGR relay) to complete the circuit through the TCC solenoid.
The Th200-4r I've got (from BTO) grounds the solenoid internally, so you'd need to modify the wiring so that the computer supplies 12v to pin A of the connector when it wants lockup in OD (& 12v to pin D if you want lockup in "3").
I did a wiring diagram for modifying mine which I can email if you PM me your email address (though it was done for the BTO unit, I haven't a clue if other units have the same internal wiring).
As long as the lockup doesn't happen in the low gears and at low revs, I doubt that you'd notice any difference in the point at which it locks.
Always though RPM was the leading factor in when a converter locks. Good thing sharper heads than mine(most everyones) chimed in!
Safety Car
Joined: May 2001
Posts: 3,758
Likes: 3
From: Surrey
I wouldn't mind checking that out, but can't as the VSS in my speedo is knackered. I can't be bothered to fix it because1) The way I've got lockup working now is just how I want it
2) I'd have to remove the speedo, send it to the US, wait for it to be fixed & sent back & then fit it again
3) 2 will cost money I can't afford!
4) No way do I want to disturb the circuits, etc, behind the dash! It was a pita last time I got involved behind there, but everything is working now & I don't want to take any risks!!!!
CA_legal_Vette, Hi. Long time, no speak. Hope things are good
Race Director
Joined: Jul 2004
Posts: 12,706
Likes: 329
From: Scottsdale Arizona
