B&M adj vacum modulator HELP

So I got a turbo 400 trans behind the 429 Cad in My Merc. It has a adj
(allen wrench) modulator. What exactly does it adjust? It was put in a couple yrs ago. Just getting ready for the Drags and tinkering with lotsa crap. Thanks FEDER

 

It should adjust, to a point, the speed and firmness of the shifts. You can turn the screw in or out to raise or lower the speed and firmness when the transmission shifts.

 

The way I understand is that if you screw the adjustment down it brings down your shift point, it also firms up the shifs. It may feel real harsh but thats what get your tires to churp 1st to 2nd gear, real hard too. Thats all I know.

 

Well, I know on a C6 you wont get the tires to chirp with just fiddling with the modulator. That kind of change in the shift feel and firmness comes from modifying the valve body with a shift kit. From what I've read the modulator only varies the shift point by 5-10mph, after that you're looking at changing internal parts to get the shifts to really start waking up.