TCI StreetFighter Transmissions 371016

This bare four-speed automatic is rated for 725 advertised horsepower on the Chevy bellhousing pattern, and unlike the three-speed StreetFighter units elsewhere in this range, it's lockup compatible and runs a 7.500-inch tailshaft that sits between the shorter and longer options found on those three-speed versions.

How dual-mode shifting works here

Shifted manually, the StreetFighter valve body upshifts and downshifts the instant you move the lever, delivering a race-track-style change that bangs through the gears; left in Drive, it holds positive automatic shifts for the ease of a normal automatic. First gear is 3.06:1, the input shaft runs 30 splines, through an OEM-style aluminum case with a natural finish.

Controller and shifter notes

This unit does not include a shift lever, and TCI recommends pairing it with an EZ-TCU transmission control unit and a dedicated four-speed automatic shifter for standard automatic operation. Past the bare case, you're on the hook for a torque converter, a cooler, a controller, and the fluid to fill it, plus the flexplate and wiring harness; the speedometer gear and housing are missing too. Sold individually.

Do I need a separate controller for the four-speed function? Yes, an EZ-TCU or equivalent plus a matching shifter is recommended. Is this lockup compatible? Yes, unlike some of the three-speed units in this lineup.