If there’s one thing I love about the car world, it’s the people you meet. I first met Bill Rader of Bill Rader Motorsports at a Las Vegas Gears & Grinds Sunday morning meetup, and it didn’t take long to realize he’s one of the best in the world when it comes to Porsche gearboxes. Lucky for me, he’s also local.
So when it was time to rebuild the 915 gearbox on my 1978 Porsche 911SC because the synchros were shot, I knew exactly where to go. And while we were in there, we decided to upgrade to a Wavetrac limited-slip differential (LSD)—because why not make it even better? If you’re into performance driving—whether it’s track days, canyon runs, or even just spirited street driving—a quality LSD is a game-changer.
What Makes Wavetrac Different?
Traditional limited-slip differentials, like clutch-type or helical-gear setups, work by distributing torque to the wheel with more grip. However, most of these designs struggle in low-traction situations—like when one wheel is unloaded mid-corner, during a launch, or on uneven pavement.
The Wavetrac LSD is unique because it solves this issue with a patented wave design inside the differential. Here’s what sets it apart:
Zero-Load Performance – Unlike traditional gear-type LSDs that lose effectiveness when one wheel has little or no traction, the Wavetrac maintains torque biasing, meaning you still get power to the gripping wheel.
Better Cornering Stability – In a classic rear-engine, rear-wheel-drive Porsche like my 911 SC, managing weight transfer is crucial. The Wavetrac provides a more predictable, stable feel through corners by ensuring power goes to the right places at the right time.
No Wear-Prone Clutches or Plates – Many LSDs rely on clutch packs that wear out over time. The Wavetrac uses a helical-gear design, which means no clutches to replace and consistent performance over the long haul.
Improved Acceleration and Traction – Whether launching from a standstill or exiting a tight turn, the Wavetrac helps put down power more efficiently, reducing inside wheel spin and improving grip.
Low Maintenance and Durability – Because it doesn’t rely on friction materials, the Wavetrac is incredibly durable and doesn’t require special oil additives like some other LSDs.
How It Transforms the 911 Driving Experience
If you’ve ever driven a classic 911 hard—on the street or track—you know how tricky it can be to manage traction. The rear weight bias gives it amazing grip when you're on throttle, but if one wheel loses traction mid-corner, things can get a little... exciting. In an open differential, power goes to the wheel with least resistance.
That’s where an LSD comes in. It helps put power down evenly between the rear wheels, reducing inside wheel spin and making the car feel more planted. But Wavetrac takes it a step further with some really smart engineering:
More confidence in corners – The rear end should feel more planted when powering out of turns. No more "one-wheel wonder" behavior.
Improved balance under throttle – Rear-engine cars can be tricky, but the Wavetrac should help manage weight shifts and keep things predictable.
More consistent performance – Whether the road is dry, damp, or uneven, the LSD should keep the car hooked up and driving smoothly.
Better power delivery – Less wasted energy means quicker acceleration and a more responsive feel when putting the power down.
Why I Chose Bill Rader Motorsports
While we were discussing my gearbox, Bill's phone rang. It was Bruce Canepa. I was about to discover that Bruce trusts Bill to rebuild his Porsche reimagined 959 gearboxes, and I immediately I knew I was in good hands. Bill and his team at Bill Rader Motorsports are absolute pros. He knows Porsche gearboxes inside and out, from vintage air-cooled setups like mine to modern PDKs. it's clear he possesses an extraordinary level of expertise. Bill invited me to join in the disassembly and reassembly process, and I was amazed during my two full days at his shop that he remembered all the steps without ever consulting a Bentley manual, the orange bible of my own garage. Having Bill rebuild my gearbox and install the LSD gives me total confidence that everything is dialed in perfectly.
First Impressions?
I haven’t pushed it too hard yet, but even on the first drive, I could feel a difference. The car hooks up better, feels more stable under throttle, and just has this smoother, more connected feel. I can’t wait to get it on some twisty roads and really see what it can do!
If you’ve ever considered upgrading to an LSD—especially a Wavetrac—I highly recommend it. And if you need Porsche gearbox work done? Bill Rader is the guy.
Have you tried an LSD in your car? Let me know what you think!
Comments