Buick version is a "switch pitch" Super Turbine 300. It has same input size as Turbo 350/400. It bolts directly to the Stage II Buick V6. I'm told "convertor" cars are more consistant at drags, vs. a clutch,(door slammer topless TR7) Two speed Lenco has 1/1 and 29% over. Anybody ? Thanks, roverman.