[Chevy454]

Was used on mid-60s Buicks I believe, to help get the hulks moving...uses a switch to change it from like 2800 stall to like 1800 or there abouts...kinda like an early lockup converter. There was a tech article about it in the GSXtra many many moons ago, so any Buick that's ever had a wrench turned on it has one, or at least it seems!