Technical Inspection

As I was preparing for the 2019 hpde track season, I began preparing the car for track use.  Any club event that you sign up for will have a pre-event check list or technical inspection form.  If you happen to register with a Porsche Club of America (PCA) event, you’ll typically be required to have the inspection form completed by a certified mechanic.  The mechanic will review and inspect a list of items, generally 15-30 items and be required to sign and date the form.  Most clubs require the inspection to occur within two weeks of the track event.

After getting the analog signatures, you bring the form with you to the event and present it at the technical check-in, either the night before the event, or the morning of.  All very manual and slightly annoying as someone who is within the IT industry.  All these pain points are adding up and I’m putting together an idea for an app, coupled with a software as a service offering.

Anyway, before registering for your first event, before getting to a technical inspection stage, you will need to ensure the car is track-ready.  Engine, transmission, brakes, wheels, and tires should be top priority.  Aside from changing the spark plugs, coil packs, oil and oil filter, and air filters, I tend to leave the bigger stuff to the dealership or an independent shop.  The Porsche PDK transmission is a black box, so that falls into the same category as the major engine stuff – I won’t touch it.  The rest is stuff I’ll take on myself.  I grew up around cars and helped my dad build a ’66 AC Cobra kit car, so I’m better equipped than most to handle the DIY service items. 

In my preseason work, I prepare the car by swapping street brake pads for racing pads.  Last year, I managed to ruin a set of rotors – or so I thought.  I was getting a vibration through the steering wheel under light or heavy braking.  I was also hearing noise through the drive train.  So noise, vibration, and harshness (aka NVH).  This can’t be good.  Upon inspection, I found that I was getting blue spot deposits on the rotors, like the size of a quarter, all around the rotors. As I was still learning how to track cars, I chalked it up to the street pads not being up to snuff for track use.  Though, as I read on forums, rotors are durable and should last more than a couple of track seasons.  So I switched to using Performance Friction (PFC) pads on the front brakes with stock pads in the rear, on a brand new set of rotors.  I ended up with the same result – deposits and harsh braking.  Ultimately, it came down to my braking technique.  I thought I was threshold braking, but I was pushing beyond threshold to the point ABS kicked in, which then explained the pattern of deposits on the rotors.  On top of that, later in to the on-track sessions, I would experience brake fade.  Keep in mind, brake fade is due to the pads getting too hot and losing their adhesion to the rotor.  Sidebar: normal street braking is abrasive braking.  Track braking is adhesive braking where a thin layer of pad material forms on the surface of the rotor.  The ABS action was clumping that thin layer of material on the rotor. 

Brake fade can create scary moments, but also has a lasting affect if not addressed.  80% of my fade issues were due to my poor braking technique.  However, once I addressed the technique, I still found that I was encountering fade.  The length of the track session contributed, as well as my improved skill was leading me to fast lap times, which then led to higher speeds, in turn creating more braking demand.  While Porsche did a great job with brake ducts on the 991, I still was pushing the limits of the car.  The heat transfers from the pads, to the brake caliper pistons and ultimately to the caliper itself.  When I was changing out pads for the 2019 season, I discovered how the heat can damage the calipers.  I had melted the dust boots on the calipers.  The dust boots are there to keep dirt and brake pad dust from getting into the caliper and disrupting the operation of the caliper pistons.  If that stuff gets in, it can lead to scarring of the piston and possible brake failure.  Not safe; not good. Guess I have another project ahead in the next couple of weeks.