I have to agree with ddd....
FOR AN "HPDE-0" or HPDE-1 driver: The stock S197 GT brakes (13" non-Brembo) are marginal with a full-weight car and any sort of pace at all. I've had students run through an entire set of pads before a weekend was up (6-7 20 minute sessions out of 8), and limping home on the backing plates, or pinching off a line to a caliper that spit the pistons out is NOT the way to bring them back to the track!
Kerry, I don't know what the "plan" is for the NZ-based groups, but here stateside, the general pedagody for a novice-level group is to focus on safety, line, and just getting used to the environment. Towards the end of the weekend, we're introducing braking/steering/throttle techniques, and giving the students the knowledge they need to continue in driver development. We're not focused on platform development or advanced skill sets at all.
For those novice level drivers, I STRONGLY prefer having street tires on the car, for a wide variety of reasons! Audible feedback is the first reason. I teach them to listen to the tires, and combine that with the "seat-of-the-pants" feedback they get from the chassis to begin to "feel" what the car is doing. Street tires also have a VERY wide envelope of performance, and there is usually a LOT of warning before they finally just completely lose grip. Race tires, on the other hand, are dead silent, and have a very narrow envelope before breakaway, which for a novice can be quite difficult to handle. Finally, the street tires do have a lower overall speed, which affords more time per lap for instruction, and lowers the "cost" of failure dramatically.
MOST novice drivers on track are hugely inconsistent. If the target is to use, say, 95% of the available grip at all times when cornering, they will typically fluctuate between 80-120%. Usually, it's "too fast in the slow corners, and too slow in the fast corners." Or, they try to be heroes on the corner entry, spend the bulk of the mid-corner phase trying to gather up the sliding, twitching hot mess, then putter out of the corner with the need for underwear replacement.
If you're on race tires, with (for example) a 10% margin-of-error, you feel like a hero at all times even when using 70% of what is possible, until you spike a control input, and then suddenly "they just lose grip, with no warning," and off you go, into the Aarmco. At least with street tires, which start talking at around 75-80%, you start to hear the feedback as you approach the limit. Plenty of warning. Then, we can talk about associating the feedback you get (brake pedal, wheel, seat) with what the tires are telling the driver. Once they begin to mentally link that little shudder in the wheel with the tires being at the edge of lockup or edge of traction, THEN they can consider stepping up to race tires. For experienced drivers, like Kerry or myself, sensing the feedback from race rubber is near-instinctive. For a newbie? It's a black art. Witchcraft.
As far as the rest of the list goes:
1) Competition alignment: I run 2.7* neg camber and 1/8" toe-out. On the street, that'll eat the tires alive, and the car is "interesting" to drive on a crowned surface. To get that much negative camber, you'll need camber plates, and possibly a cut strut tower. Hardly things you'd want for a first-timer.
2) Race pads: IMO, thing number one. You learn nothing if you're parked in the paddock with no pads left. Getting to temp in a full-weight car is NOT hard, and HPDE doesn't have the charge into T1 that you do in a race group.
3) spare wheels and scrubs: Last thing to do before you start in a competition environment (Time Trial or W2W).
4) Springs: Chassis development item, along with the alignment, and IMO the most critical part: dampers. Proper dampers go a LONG way towards "managing" the ills of the chassis. Given a choice between a set of springs and bars, OR a set of Sachs or Moton dampers, I'll take the dampers every time.
5) Seat/harnesses. Also chassis development, albeit quite a bit earlier than the rest of the list.
Remember that we're talking about somebody who has potentially NEVER put a wheel on a track before. They still have highway following intervals ingrained, tend to drive with one hand at 12:00 and the other on the shifter, and have no concept of taking a corner "outside-inside-outside." They have no frame of reference when it comes to braking points (never mind consistent braking pressures), and tend to treat the gas pedal like an on/off switch. These are the budding racers of the next generation, and if they get the sense that to even START doing this requires a $10K investment and potentially irrevocable changes to their brand new car, we won't get them to the track in the first place. These are the drivers that we're trying to instill the mental aspects of performance driving (situational awareness), as well as teaching them the physical skills (control input techniques, problem recovery).
I stand by my recommendations for first-timers.
Now, for somebody with a couple of weekends under their belt, things change, and rapidly. They understand why the brakes are so important, and actually know that you can buy race-dedicated compounds from PFC, Hawk, Carbotech, and others. They get why ducts are so important, and have already planned on them. They "get" the concept of the line, and are starting to become more consistent. They understand why an early turn-in is the worst possible sin. THESE are the guys where starting a bit of chassis development makes sense. They know they're coming back to the track, and a $300 set of camber/caster plates makes sense to protect the outside edges of the tires, if for no other reason. They're at the point where they can consistently push the chassis hard enough that they are starting to identify the weak points that "need" correction, and can do so intelligently, rather than throwing a parts-list from a shiny catalog at the car. These are the folks that are already hooked, and just need guidance on the how/why for modifying their chassis.
Then there's the final 10%. Knuckleheads like us who have taken a perfectly good street car and absolutely destroyed the quality of ride, all in the pursuit of that one golden lap (TT) or being that little bit faster than the other guy (W2W), and have gone broke and gotten divorced in the process!
You might be a racer if:
1) You have a jungle-gym installed on the inside of the car.
2) You late-apex your driveway.
3) You heel/toe going into your garage.
4) The only wear on the brake pedal pad is on the right-side edge.
5) You throttle-steer on highway ramps, and usually at double to posted advisory speed limit.
6) You have to refrain from bump-drafting the guy ahead of you on the highway.
COST AS BARRIER TO ENTRY: The entire concept of HPDE is to take your existing street car an experience the joys of running around in circles, turning fossil fuels into heat and noise. There is already a fairly significant cost right up front for the entry fee ($400?), not to mention the general wear-and-tear on the car. If "we" pile a laundry-list of other things needed just to TRY OUT this whole scene, we'll decimate the incoming ranks. Look at Kerry's list for a moment: Alignment: $100 before the event, $100 after (back to street settings), $300 in caster plates, $200 installation labor: $700. Race pads: $250-300. Necessary, IMO. Wheels/scrubs: $800 for cheapie wheels, $400 for scrubs, $120 for mount/balance: $1320. Springs: $400 (installation and alignment covered above). Seat/harness: $1000 seat, $300 harnesses, $250 brackets and seat-mount, $200 harness bar (should be a full roll bar) $300 labor. $2050. This list totals $4470! If every potential newbie to the sport is faced with dropping $5K just to give it a try, we're going to have NO enrollment, and the sport will die. That's just simple economics. NONE of the above (except the brake pads) are actually necessary to go out and enjoy the car at an 80% pace. IF the bug bites, and you decide that yes, this is my new avocation, then absolutely start buying parts, and learning to work on your own car. Until then? Bollocks. Get in it and drive.
Racer tip for warming up the brakes and tires: Slow, gentle weaving side-to-side is great for cleaning clag off the tires, but does NOTHING to put heat into them. For that you need to slide them, and that takes aggressive, sharp control inputs. Yank the wheel hard over and goose the throttle to induce understeer to slide the fronts. Yank it the other way and stab the brakes to induce oversteer to slide the rears. On a race group sighting lap, that's what I do for the first half-lap. The rest of the lap I spend accelerating aggressively then slamming on the brakes to get some heat in the pads. Once we pull into formation (2-wide for the final 2-3 corners), I'll drag the brakes all the way to the green flag, to get heat into the hubs and wheels. Gets the tires up to temp quicker, and makes sure the pads have plenty for the turn-one scramble. Also remember that on a race start, you're not moving anywhere NEAR as quickly as "race pace" into the first corner, so you CAN push your braking point a lot closer to the corner. A lot of drivers forget that, having a programmed braking point, and you can take advantage of that error if you stay heads-up.
For the HPDE crowd: The above tricks are NOT applicable to HPDE!! If you run race brakes, then yes, the accel/brake thing helps, but unless you're on race rubber, forget about the weaving/sliding thing. Even if you ARE on race rubber, forget about it, since you SHOULD be warming the car up incrementally with pace. There is no premium on the turn-one/lap-one thing, and you have no excuse to "charge into" a corner until you've got the car (and your brain!) nicely warmed up.