Converting a 1978 lockup 727 to a non lockup , will a 1971 valve body work ok , thanks

When you mean converting it, you simply do not want lockup. That’s it?

Correct , just wanting to know if a 71 vb. will work with the 78 case that had the lockup vb .

If you want to disable lockup just block the lockup valve. No need to switch valves bodies. On the 78 there is a lockup module with an aluminum tube running to it.
Just block the valve by replacing the spring inside with a plug.

But I believe you can't use a standard converter unless you switch the pump/input shaft. Different splines?

Ok , that's what I've done , changed all that for non lockup , that is why I'm asking if the 71 vb will work with the 78 case.

Anyone might know?

IIRC yes the 71vb will fit the 78 727 as you have converted the spline/TC to non lock up.

IIRC the 71 VB will NOT have a PTK valve. you can use a housing/spring/valve from a /6 904 trans on the 71 VB for a PTK. (IIRC this is what I did for my 67-727 for PTK)

IIRC the 78 VB would have PTK with a downshift limiter built into it.

904 and 727 lock up trans I have had, I blocked the valve and order up a fresh lock-up TC with out the clutch ring/guts in the TC and use the non-lock up spline/shafts to save on teardown and parts.

but then again I have broke and killed more than I have ever been able to fix so hopefully someone will confirm for sure 100% + for you.

I have a good 78-727 VB on the parts shelf if you would prefer to use a 78 VB in the 78 case. PM me if you are interested.

I answered your question earlier. Why do you want to install a different valve body ?

Because you have a shift kit for that year or another reason?

If you want to disable lockup, just block the l/u valve in the module. The module is the aluminum unit with the aluminum tube running to it.

Maybe I didn't explain it enough , l do not want a lockup 727 , I have non lockup stahl converter I want to use , changed the components for non lockup , and have a 1971 vb I wanted to use and was not sure if it would work in the 1978 case . I want to save the lockup vb for another time and the other parts . I thank you for the reply .

If you have replaced the front pump assembly, input shaft and rear clutch piston retainer to pre-'78 non-lockup parts (or '78-later non-lockup parts), then, yes you can use the '71 VB. The factory has stated that the lock-up case can be used for "prior model service".

Thank you