Can the xfi control the converter lockup on a 999 torqueflite?

I thought the converter lockup on the 999 was hydraulic and automatically activated at a certain speed?

Here is what my tranny guy wants to do. Take my 904 with the gear vendors on it and install the guts to use a lockup converter.
Then we will use a reverse manual vb, so it will not be able to control the lockup hydraulically. Then we will have to control the lockup with a switch.
I saw that the xfi can control a lockup converter but I dont know if it would control this or not.

You need a new tranny guy. A regular A999's case doesn't have the passageways a lockup version uses. It isn't a matter of just adding the guts.

I think some of the very late ones were electrically operated, but you'll still have to get the complete trans to make it work.

999 lockup is strictly a hydraulic function, some later ones have an electrical connection used for UNlocking the converter under certain conditions.

John:

Conditions such as applying the brake? Vehicle will stall when slowing to a stop with converter still locked, correct?

I don't think it was for the brake. I think the earlier 999's with the strictly hydraulic lockup locked/unlocked the converter at a certain speed, regardless of throttle position. Meaning wide open throttle put a lot of strain on the converter lockup clutch. I'm guessing the unlock feature was to aid in higher load conditions to keep the converter clutch from burning up?

The electronic lock up was mostly to keep it un-locked at high throttle angles and mabey when cold.

Without the passages in the case you can not add lock up, well it could be done but would require a lot of money and engineering and be waaaaaaaaay more expensive than just swapping trannys. Just find one of the electronic controlled lock up trans and have it rebuilt and add your GV, it is not expensive or hard. When you go to the bone yard look for a van 89-95 with a 904 or a 89 mabey 88 V8 diplomat/5th ave. If you look on the option sheet and it says 32RH you probably found the right trans, look for a trans that looks just like a regular 904-999 and find the aditional electrical plug in near the shifter.