VCCA Home Forums TECHNICAL - 1945 AND NEWER 1965-1970 Tranny Lockup wire

I installed a 2004R tranny in my 68 El Camino. Where is the best place to connect the lock up (purple) wire from the tranny?
I tried the brake light switch but that didn't work, it made the engine die coming to a stop.
ANY ideas?
Broo

The engine stalled because when you applied the brakes the brake light switch applied 12V to the trans converter clutch and locked it up, much like stopping a manual transmission vehicle without stepping on the clutch. It takes 12V applied to the converter wire to lock the clutch. Originally that function was controlled by the ECM and I suspect you aren't using one and if you are it would need to be one that had that function built in.

Normal opeation of the converter clutch occurred at vehicle speeds at or above 40 mph and would automatically disengage with the brake were applied or when coasting somewhere around 4 to 5 mph. Throttle position was also a controlling factor.

If it were mine and I wanted the converter lock up function to work, I'd wire in an on/off switch and control the thing manually.

ok that seems less expensive than those kits at $90 Is there a minimum on the switch size?

There are kits in the after market that will do that and I know some will do the lockup by a pressure switch after the trans is in 4th gear. Check with some of the street rod vendors.

Here is a link to an article on the subject: http://www.73-87.com/7387garage/drivetrain/lockup.htm -- Wiring A Lockup-Converter Pressure Switch

Thanks so much! That really helps.
broo