Anyone running a 904 behind a 340?

Bakerlite said
Maybe before you tell me I'm incorrect,you should study this.
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No they don't.. I think your still a little mixed up with what actually does what.
If you released the low band as soon as you let go of the switch, then you would also have no 1st (low) gear.. It would be in 1st (Drive):rolleyes: with the sprag carrying all the load.
The transbrake uses 1st (low) and Reverse at the same time to lock the trans.
Can you tell what gets released to unlock the trans? (Hint, it's not the Low-Reverse band.)
You don't jam a super sprag in there to try and fix the issue, you lock the Low -Reverse drum,which is a better, stronger way of doing it.
The whole idea of applying the Low band is to prevent 1st gear shock loading to the sprag..and engine breaking.
If your going to load and unload the trans off the start line in 1st gear, then your going to want that Low band applied.
That's why Chrysler designed it that way..

I understand exactly how it works. The chart you posted is for a bone stock tranny. A transbrake is not bone stock. Ask yourself what is gained by a billet bodied transbrake.
This is not my explanation, it is the explanation of reputable builders. Turbo action uses a timed release. Others leave the band on right until second gear is pulled. The front drum unlocks the trans, but that has nothing to do with the 1-2 shift. What I am saying is that some brands leave the low band on longer than others. The longer it is kept on, it becomes difficult to get a clean 1-2 shift.
The second gear band could potentially be on at the same time as the low/ reverse band causing a bind up in the 1-2 shift. But this method fully protects the sprag. To get around this problem, the servo spring pressure, size of the fluid passages and minimal low band adjustment achieve a clean 1-2 shift with the band on right up until the 1-2 shift. Some brands of low band apply brakes still can damage the roller clutch in certain conditions. Why is it common practice in any 727 build to upgrade the roller clutch. The 904 is no different.