B&m converter Lock up control
Thread Starter
Burning Brakes
Joined: Jul 2004
Posts: 1,194
Likes: 111
From: If your not the lead dog the view never changes Boise, Id
B&m converter Lock up control
I just installed a 700R4 in my 78, I used the B&M controller for the torque converter lock up. This unit has on its face a dial to control what speed lock up occurs and a button to turn it off and on. On the bottom side of the unit next to where you plug in the wires to is a switch. This switch is never mentioned in any of the literature or instructions for this unit except in a diagram where it says " slide switch". I want to sink mount the control unit so just the face is showing but that would make this switch unaccesable, does anybody know what this switch does
Thanx
Thanx
Melting Slicks
Joined: Jan 2014
Posts: 2,478
Likes: 254
From: Downers Grove Illinois
It is an override switch to disable the lockup feature. I found this online with a Google search:
"Figure 1" of the instruction sheet has a notation to slide the switch to the right (IF using mechanical speedometer input.) You MUST slide this switch to your right or the unit will NOT function.
"Figure 1" of the instruction sheet has a notation to slide the switch to the right (IF using mechanical speedometer input.) You MUST slide this switch to your right or the unit will NOT function.
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
The ECM controlled 700R4 uses vacuum, TPS and a speed sensor. For example my 82 with the hypertec prom installed holds off any lock up until the car reaches 45 mph.
With the original Prom the lock up would occur at low speeds and it was annoying as it popped in and out. Jerking the car or lugging would occur.
With the original Prom the lock up would occur at low speeds and it was annoying as it popped in and out. Jerking the car or lugging would occur.
Thread Starter
Burning Brakes
Joined: Jul 2004
Posts: 1,194
Likes: 111
From: If your not the lead dog the view never changes Boise, Id
So would I be right to assume that the switch should really never need to be moved once installed as long as it is set to the right when I mount it?
Thread Starter
Burning Brakes
Joined: Jul 2004
Posts: 1,194
Likes: 111
From: If your not the lead dog the view never changes Boise, Id
Thank you I already have the B&M controller and am very happy with how it functions. I was just asking about the slide switch
Melting Slicks
Joined: Jan 2014
Posts: 2,478
Likes: 254
From: Downers Grove Illinois
Drifting
Joined: Mar 2006
Posts: 1,263
Likes: 188
From: Wabasha Mn
Agree with toobroke on the 4th gear pressure switch swap for those wanting an inexpensive lock up system. With the normally open pressure switch installed and the tcc solenoid ground wire going to this switch you will have lock up only in 4th gear. Your brake pedal switch will unlock the tcc when coming to a stop. You can have a separate toggle to unlock the tcc at will. I never lock my tc until around 55 mph.
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