The Kartboy shifter is beautifully made. Almost every part is a custom-machined of metal. It's hefty and solid in the hand. All the moving parts are pre-greased, and an additional syringe of grease is included for the install.
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I hopped in the car after it came down on the lift, and put it in reverse, then drove out into the neighborhood around the shop. Hey, what do you know? The feel is tighter, click-ier, more precise feeling. I know it's a cliche, but it feels like a bolt-action rifle. No slop, no give, just a tight, mechanical, direct connection to the gearbox. The slightly (0.35") lower shift knob height feels just perfect to me. The reduced throws make the shifting feel quick and sure.
So, to sum up, I'm sold! It's an improvement over the stock shifter. Good job, Kartboy.
Kartboy short shifter for FR-S/BRZ