Traction, Anyone?

The S13 and S14 LSDs are KAAZ’s...        read full caption The S13 and S14 LSDs are KAAZ’s bestsellers in Japan. The Silvia kits are very complete and come with the differential cover gasket, oil seals, and bearings.

Few engine swaps can moisten our panties quite like replacing the KA24 in a 240 SX with a turbocharged SR20DET from the Japanese S15 Silvia.

Executing such a swap, however, represents a considerable investment of time and resources. Considering what Ricky Chu has invested in turning his ’95 240 SX into a dreamy Silvia replica, he would’ve had an easier time importing a gray-market S15. Of course, hindsight is always 20/20.

Having replaced the critical driveline pieces with the far more desirable Japanese-market components, Ricky has begun focusing on the performance details. Between making the rounds on the show circuit and trying to talk unsuspecting girls into signing up for his “modeling agency,” Ricky has been looking to improve the traction of this hybrid Nissan for strip and drifting chores. What he needs is a device to maximize additional power and distribute traction equally between both rear wheels under open-throttle conditions. Such an infusion of driveline manhood comes in one form: an aggressive 2-way limited-slip differential.

That’s where the KAAZ limited-slip differential enters the picture. It uses spider gears and pressure plates to load a clutch pack that inhibits the slippage of the rear wheels. In open differentials, the power is diverted to the wheel of least resistance, which on a hard turn is the inside wheel as it is lifted off the ground by the shifting weight of the body. Imagine trying to row a canoe with one oar; you’re not maximizing your power-distribution potential. With weight lifted off the wheel, it spins and squeals; as a result, the vehicle doesn’t make the most use of its power to propel itself forward and thus slows down. A limited-slip differential, however, distributes the power evenly between the two rear wheels while allowing for a minuscule amount of differential movement. Through the same turn on an LSD-equipped car, the outside wheel turns just as fast as the inside wheel, moving the car through the turn without the loss of traction.