Originally posted by Blasphemous
I can't remember the company, but someone out there makes several different converters for "switch-pitch" TH400 trannies.
Torque Converter: Custom "Switch-Pitch" stall converter. Low stall at 1850rpm, High Stall at 4000rpm.
Switch-Pitch Info: For those of you unfamiliar with a switch-pitch, it is a custom converter with movable vanes which allows them to change pitch and vary the stall speed. The transmission required a special input shaft (ours is hardened in this case) and front pump housing for a solenoid. The solenoid raises the fluid pressure which changes the pitch of the vanes in the converter. This allows you, at the touch of a button, to change your stall speed. High stall converters are great at launch, but are very inefficient everywhere else because they allow slippage, that's what enables them to stall so high, so you don't get those tire-barking shifts. With a switch-pitch, I can launch in high-stall mode (4000rpm) and as soon as the vehicle settles, press the button on my shifter and it will lock up the torque converter instantly barking the tires as if I had shifted gears. It will continue to bark the tires through the rest of the gears because the torque converter is fully locked up. This makes for more fun on the street and better quarter mile times. How often to you get to get your cake and eat it to?
From the 454SS truck that was posted in eye-candy a little while ago.