The Fabulous Flog: A Look Inside Dai Yoshihara’s Falken Tire Subaru BRZ


A KRC power steering pump is used.  The pump has tunable assist levels controlled by pills of different size and an adjustable regulator. On a drift car the power steering gets quite a workout and having the tunable assist allows tuning for steering ease vs feel. 
A large cooler for the power steering system under the car is fed air via this scoop.  The power steering fading in the heat had been a developmental issue with the car and the cooler has just been upgraded.
In drifting, minimizing shifts has been important as it is one less thing for a busy driver to do.  In a short duration event, shift time is lost time.  More shifts also means more chances for driver error.  To reduce the amount of shifting, the team uses a quick change differential to get the perfect ratio for each course.   Typically the shifts are 1 though 4 going into the first tun, then a single downshift somewhere in the course. The engine's super wide powerband and good gearing allow for this.  The gear ratios can be changed in 5 minutes or less.  Quick release joints on the differential crossmember allow for quick differential changes in case of failure.
The differential is made by Winters and has a 10.5 inch ring gear, huge to take the stress of all that power.  A spool differential is used as this is what Dai prefers.  The spool needs some special chassis tuning to reduce understeer during turn in.
This sturdy steel loop catches the driveshaft in case the heavy duty Spicer U joint or the custom chromoly driveshaft itself fails.  This prevents a flailing driveshaft from penetrating the floor or causing the car to pole vault. 
The Driveshaft Shop built these custom 300M axles using billet cased Porsche 930 inner and GT-R outer CV joints.   The axles are very strong and rarely fail.  The axles are designed to twist and absorb shock.

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