As the track 2021 season approaches - it’s already started for some folks - I’ve got several track days booked and some upgrades planned for the radster. Most of these upgrades focus on safety, reliability and drivability with some slight performance improvements hopefully gained.

I planned to do most of these in 2020 at AR Motorsports in Tigard, Oregon. Then COVID hit, the borders closed, and most of these parts were stuck there. I finally decided to ship them up to Canada and do the work locally.

Brake Master Cylinder

Two years ago I installed an Essex AP Racing Big Brake Kit on the fronts. This made a massive difference over the stock brake setup. I personally think the brakes on the Z4M are the most inadequate aspect of the car in comparison to every other performance impacting part.

However, I figured out that my master cylinder was failing, likely due to the internal seals having some tiny leaks. This is not unusual for a 15-year-old car. I am replacing this for the 2021 track season.

Core 4 Motorsports Hubs

I have never owned a BMW before. Nor have I owned a car that uses bolts and not studs. I found bolts to be a pain when servicing the car, so I did a stud conversion. After watching many videos of stud failures, I decided to install the very high-quality Core 4 Motorsports hubs.

VANOS High-Pressure Line

I decided to install this as a precautionary item. My shop indicated the stock one was starting to weep oil at the seals. I bought the exact fit replacement line from ECS tuning.

Driveshaft guibo and driveshaft bearing

Also a precautionary maintenance item, I decided to replace the driveshaft guibo and bearing with a kit from ECS.