[oneday]

Subaru has an on-again/off-again relationship with customers who track their cars. When the WRX was first released in 2002 they gave buyers a membership to the SCCA, then (reportedly) would deny warranty services to those customers later on.

Working in the aftermarket, I can tell you that every dealership/service writer is different and you need to have conversations about your planned mods/activities before you commit to a specific service department (remember service departments are not always in agreement with the dealership--they are often run as separate businesses). Some writers will let you get away with anything, others are just plain old sticklers for the rules.

The bottom line: If you are worried about retaining your warranty do not modify your car. If you are not able/willing to completely write off the car do not take it to the track (even for an HPDE).

As for what mods for HPDE duty BRZ/FR-S: Brake pads, brake fluid, and good, synthetic motor oil filled to the appropriate level. If you are doing a lot of tracking (8+ a year) accessory gauges wouldn't hurt at all. Primarily, I'd be looking at oil temp and oil pressure. If you are getting the AT then a trans temp gauge might be a good idea too.

It's tough to predict how durable the internals of this new powerplant are going to be, but I would guess that unless you are really upping the power beyond normal NA realm, you will have no issues in flogging this on the track a few times a year.