Tom’s Spec Boxster: Another Year of Refinement

Tom’s Spec Boxster is back in the shop for another round of updates.

At this point, it has kind of become an annual thing. He gets another season of racing in, learns more about the car, comes back with a new list, and I get another chance to clean up a few things, simplify some systems, and make the car a little better than it was the year before.

This time around the focus was mostly on weight reduction, simplicity, driver comfort, and getting better data from the car.

Deleting the Accusump

One of the bigger changes this year was getting rid of the Accusump oil system.

With the newer high-capacity sump available for these cars, the Accusump had started to feel like more complexity than it was worth. It added weight, extra plumbing, more fittings, and another system that had to be maintained.

The updated sump gave us a much cleaner solution, so the Accusump, lines, and associated hardware all came out.

Less weight, fewer potential leak points, and a much simpler oiling system overall.

That’s kind of the direction this car has gone over the years. If something can be made simpler without giving up function, I’d rather remove parts than keep adding more.

New Coolshirt Setup

Tom also wanted to add a Coolshirt system for longer races and hot track days.

Rather than just strapping the cooler down somewhere in the car, I wanted it mounted cleanly and in a way that didn’t require drilling a bunch of new holes into the chassis.

I designed a laser-cut aluminum floor mount that attaches using the factory seat mounting locations, which made it easy to install securely while keeping the whole thing removable.

I also designed and 3D printed custom intake ducts for the system to help get airflow where it needed to go.

It ended up being a pretty compact setup and looks like it belongs in the car instead of something that was added as an afterthought.

Redesigning the Transmission Cooler

The transmission cooler ended up being more than just something I wanted to clean up.

The old setup had the pump mounted inside the cabin, which was already less than ideal. It was loud, took up space, and there was no easy way to know whether it was actually moving oil.

Once I tested it, I found out it wasn’t flowing at all.

So at that point, the old system wasn’t just inconvenient. It simply wasn’t doing its job.

Rather than try to patch the existing setup, I decided to start over and build something more compact and easier to trust.

The new system mounts the pump and heat exchanger directly at the transmission using a custom bracket I designed and fabricated. I also built a dedicated air duct for the heat exchanger so it gets proper airflow while keeping the whole package tight to the transmission.

That got the pump out of the cabin, shortened the plumbing considerably, and put all of the transmission cooling hardware together in one compact package.

More importantly, the car now actually has a working transmission cooler.

Multi-Channel Tire Temperature Sensors

One of the more interesting additions this year was a set of multi-channel tire temperature sensors on all four corners.

Instead of just checking tire temperatures when the car comes back into the pits, Tom can now see what is happening across the tire while he is actually driving.

That gives us a much better picture of how the tires are being used throughout an entire race.

It should make it easier to make educated decisions on things like camber, toe, suspension setup, and tire pressures instead of trying to figure everything out from a few measurements taken after the session.

It can also tell us quite a bit about driving style.

If one section of the tire is consistently overheating or one corner of the car is being worked harder than the others, we now have actual data to look at instead of just guessing.

For a car that is already pretty well developed, this is the type of data that can help start finding some of the smaller improvements.

New Shifter and Cables

The shifter assembly and shift cables were also replaced.

The new setup gives Tom more adjustability and a much more positive shift feel.

It’s one of those upgrades that doesn’t really sound that exciting on paper, but it makes a noticeable difference from the driver’s seat.

A cleaner, more precise shift just gives you more confidence that the gear is actually there, especially when things get busy during a race.

Another Year, Another Round of Improvements

There wasn’t one giant change to the car this time around.

It was mostly a collection of smaller improvements based on another year of actually racing it.

The Accusump came out and the oiling system got simpler. The transmission cooler was completely replaced with a compact system that actually works. The Coolshirt system is properly mounted and integrated into the car. The tire temperature sensors give Tom a lot more information to work with, and the new shifter setup makes the car nicer to drive.

That’s really what I like about continuing to work on the same race car year after year.

The first time around, you fix the obvious stuff.

After that, it becomes more about refinement.

Tom gets another season in the car, figures out what he likes and what could be better, and then it comes back in for another round.

Each time, the goal is pretty much the same: make it simpler, lighter, easier to use, and hopefully a little faster.