The Porsche 996tt at Auto Club Speedway – First Event With a Whole New Kind of Car…

I like big buts and I can not lie…you other brothers can’t deny…

So, I just got back from my first track day in the 996tt. It was at California Speedway, the Roval config (AKA the Grand
Am config), which, aside from WSIR, is probably the best track for the 996tt. I had the car prepped for the event by Hergesheimer, which consisted of an aggresive street alignment, PFC 01 brake pads, brake fluid flush, and an oil change. Total bill? $1500. That seemed a little steep. The PFC pads are expensive, which I accept, but $800 in labor tells me I think I’ll be swapping my own pads going forward, thanks. There were other issues with the service as well which gave me pause…for instance they told me my brake rotors were warped. No question there was vibration under braking, but it was probably due to pad deposits on the rotors, not the “mythical” warped rotor. They were suprised when I told them not to change the rotors, which was going to cost $500 for a pair of fronts. They warned me that I was going to flat spot the tires as a result of the variable braking torque of the warped rotors. I gave up and just said “That’s alright, let’s not change the rotors.” My thinking was that the extremely aggressive PFC01s would very quickly machine off whatever depsoits had been laid down by the stock Textar pads, and the vibration would go away.

Another worry was that Hergesheimer told me that “While the PFC pads don’t care what other pads you’ve used before on a set of rotors, you can’t then put stock pads back on with those same rotors, as the pads “change” the surface of the rotors, and you’ll have diminished braking torque.” I’m paraphrasing, but that’s the gist of it. Now it might be true that the PFC material will not work with the stock pads well, but I’ve never had issues going between different pads on the same set of rotors. I would also expect it to be a short-lived phenomenon. I decided I’ll just deal with it if it proves to be an issue. If I was more of a cynic, I would think those guys REALLY wanted to see me a set of rotors…or two.

Baby needs a new pair of shoes…but hey, at least the wear is nice and even!

When I bought this car a few weeks ago, I drove it 3500 miles home form Maryland. Over the course of that drive, the rear Michelin PS2s corded. I needed new tires, and because this is a street car and I only have one set of wheels for it, I needed street tires that could survive track use on a 3600lb car. Now I’m no fan of Michelin tires because they’re expensive as hell, for no good reason. They’re not better. They’re not stickier. They’re just twice as expensive as Toyos, Nittos, etc. I decided to try the Hankook Ventus R-S2 Z212. I’d heard good things about them, and they were available in the 315/18 size that I needed, while a lot of other tires were not. Being the son of the the Great Depression that I am, I could not, however, bring myself to just toss the Michelins on the front of the car which were like new. I knew this wasn’t going to be ideal, running different tires front to rear, but the reviews showed the tires were similarly sticky, and I figured they would work together well enough to get through a few events and eat up the fronts. This would allow me to get something out of those fronts and get an idea of the qualities of the Hankooks to see if I wanted to stick with them, or try something else. My only real concern is that while the Michelins started out as sticky as the Hankooks, I don’t know how old these tire are, and how well they’ll match to the new Hankooks.

When the Hankooks arrived, I knew I was screwed. These things are rated at 200 treadwear, so way up there, a long ways from a “DOT-R” tire…but they’re gummy as hell. They feel more like a 100 treadware tire, and they’re certainly way, way stickier than the Pilot Sports on the front of my car. So while I’m super impressed with the Hankooks, I know I’m going to have some major understeer to fight though. Such is the life of the “thrifty” track driver. The question is, how much time am I going to lose on corner entry with this setup?

Now there’s something you don’t see everyday.

The morning of the event finally arrived (Sept 20th), and I drove the Porsche to Cal Speedway excited to see what it would be like. When I last ran this config, a few months ago, it was the first time I’d driven my T1 Z06 in about two years. I drove it on the original set of Nitto NT01s I’d ever bought, which the car had been sitting on for the last couple of years, so needless to say, the tires weren’t too great. I ran a best time of 1:55.942. That’s about 4 seconds off the time Oli last ran in his T1 C5 Z06, and Oli usually runs Hoosiers, so I was pretty happy with it considering the tires. In the Porsche, I was hoping to get somewhere near the same neighborhood, maybe a 1:56 or so. On the one hand, my Z06 is much better setup for the track. On the other hand, I expected the braking to be better in the Porsche, and the extra 50 or so HP to make up on the straights for some of the lost corner speed. I also figured the NT01s I’d run on the Z06 were old enough they were no better than street tires by this point. Well, I almost calculated all that right…

Yes, This car is for sale, cheap! I mean it this time. It has got to go, so buy it!

At this event, I was running in the “Semi-exclusive” group, AKA the “Supercar Group”. This is a group for people with cars that cost >$100k, and there are two basic ideas being the group. The first is that these people are going to be very careful when passing each other. The other idea is since these guys are “rich”, they don’t mind paying twice as much to have half as many cars on track with them. So, I chose this group because with 15 cars on track, how much traffic could there be? I pitted my car in the garage and surveyed my run-group mates. Mclaren SLR, Ferrari Stradale 430, plain old F430 Spyder, Ultima GTR, Noble, Ford GT, GT3RS, GT3, GT3, GT3, 996 Turbo, 996 Turbo, 996 Turbo, and the least attractive F-car of the last 30 years, a 465, in “Champagne” of all colors. Finally, an answer to the age-old question, “How do you make a 465 even uglier than a 1972 308? You paint it the color of piss.” AFAIK, that makes it the least attractive F-car EVER.

So, the time finally arrives to go on track. Not having driven a car like this on track before, least of all on street tires, I wildly guess how much my pressures will rise on track. I set the fronts to 33lbs and the rears to 40lbs. That’s very high for the rear pressure, but I’m assured by the Porsche world that you want very high rear pressures on these cars, like 44-48lbs hot on street tires. There’s much debate about the proper pressure stagger for these cars, but the factory recommends a huge stagger, so I decide to go with it and see what happens. The first session is good. The car is understeering incredibly, probably half due to the older front tires and half to needing wider tires than the 235s on the front (315s in the rear).

Driving an AWD car on track is extremely weird, and I spend the session trying to figure out how to work with the strange driving charecteristics, rather than fighting it. What I eventually decide is there’s not much to do about the understeer. You can trail-brake a bit, but I’m not willing to do so as much as I would in one of the cars I’m more accustomed to tracking. Among other things, I don’t have a harness, a HANS, or a rollbar in this car. So I’m somewhat conservative. I adopt a very slow in, fast out approach on the lower-speed corners, and am rewarded with nice, smoky burnouts out of each corner. Strangly, I think it was just the inside two tires spinning, though I may have been mislead by the odd felling in general of the AWD. All I know is some tires were spinning, and looking in my side view mirror there was a decent amount of smoke and a single black line from the apex to track out, that I could see in the brief time I had to look, anyway.

The car was extremely stable acclerating out of these corners, and the only thing that wasn’t confidence-inspiring was getting on throttle before you were pointed in the right direction, as if the wheel was still turned, once you got on the gas, the car would seem to want to understeer its way just past the trackout point, which usually contained a big “pothole”. Rather than being able to use the throttle to move the nose inside, as you can in a RWD car – particularly a mid-engined one – the Porsche would simply plow in a greatly expanded arc with the throttle down. So I had to tighten and slow my line, sometimes stabbing the throttle a couple of times, to get it pointed where it needed to go. Then it was just another drag race to the next braking zone.

That trail behind my car? Yeah, that’s brake dust. 450HP x 3600lbs x (3 x 125mph to 40mph braking zones per lap) = a serious toll on brakes.

The brakes were excellent. They felt very good. Braking distances were much larger than in the Lotus or the Ultima, of course, but the brakes were nice and confidence-inspiring. Only once did I get on the brakes hard enough that full ABS stayed engaged for a prolonged period, which extended my braking zone. The car broke much better without fully standing on it, it seemed. Part of that might be psychological, as when you simply stand on the brakes, the pedal raises a bit, you lose all brake feel as the ABS does its thing, and you basically feel as if you’re no longer in control of the car. After doing that and over-shooting a corner badly, and barely staying on track as a result, I mellowed my braking a bit and all was well. On the plus side, the vicious bite of the PFC01s “trued” my “warped” rotors after a handfull of laps, and the vibration was completely gone. It’s always nice when a wild-ass hypothesis pans out and saves you $500.

You call those 330mm 996 discs brakes? Those aren’t brakes. These are brakes! Unfortunately, they’re also probably $20k for a set of rotors. (F430 Scuderia Carbon-Ceramic rotor)

The power was excellent. Cal Speedway is highly variable, as many of the turns are defined by tire barriers or cones that move a bit from event to event, so it’s hard to compare corner exit speeds or terminal velocities between events, but by any measure the Porsche did very well. I was typically at an indicated 137 – 140 at the start finish line. I was at an indicated 152 before braking for the Oval turn 1. I know from GPS tests I’ve done my speedo measures a consistant 4mph over the GPS speed, so 148 on the front straight is damn impressive! I would then brake like hell down to about 125 for the Oval portion of the track (turns 1 and 2). I was not terribly comfortable going any faster than that, and by the end of the first session the rear tires were starting to feel really greasy, so it’s good it was time to come back in.

Back at the pits, I checked my tire pressures. 42 front, 54 rear. No wonder the rears felt greasy. I lowered the pressures to about 36 front and 43 rear. I say about because I somehow misplaced my good tire gauge, and I was using one of those $1.99 tube gauges, so all I can really say is three lines above 30 in front, and the top of the “4” in the rear. Not that precision would have helped to much with the tires on the car. I went to the driver’s meeting, where someone the only issue anyone complained about was a silver Porsche. I thought back upon my session, and I couldn’t remember doing anythign wrong. Turns out he was about to be passed by the piss-colored Ferrari and he made an unwise move. Whew, not me, I wasn’t passed that session.

The times finally arrived, and the moment of truth was at hand. I wasn’t thrilled to read a 2:00.something as my best time for the first session, but the tire pressure change should help. And right about then, it was time to go out for session 2! The nice thing about the “semi-exclusive” group, was it ran every 40 minutes or so, so you got your 4×20 minute sessions done by 1pm, and then you were done for the day. It’s kind of a nice, quick format if you plan to get home to the family.

In session 2, I got down to a 1:59.8 or so, still trying to figure out the best approach to corners with the massive understeer. I know some of you won’t be happy with this “test” as the front tires were very different from the rear, but I can assure you it wasn’t all tire; much of it was mechanical. It seems the 996 gives too much bias to the front of the car in its power distribution. A result of the front-driven wheels is the steering reacts in odd ways – meaning ways a RWD-accostomed driver doesn’t expect – when you get into the throttle. I’m not sure I can describe the phenomenon, but basically the steering weight varies depending upon how much throttle you’ve got applied and what you’re trying to do. It also moves around a bit in unanticipated (at least by me) ways on throttle, or when transitioning off throttle. The steering doesn’t “self-center” the way RWD cars do either, which is also disconcerting. Another driver I’ve known for quite a while who has recently bought an AWD R32 Skyline and I were talking about it at the event, and we both wondered at how, well, wierd driving an AWD car is at the track. It certainly takes some adjusting to, and I only hope it will become less distracting as I become more familiar with the car on track.

The Scuderia’s diffuser shape is highly unusual, and appears to be much smaller in area than the 360’s tunnels. Ferrari says it’s more efficient, and was based upon discoveries made during development of the FXX.

Now it’s not all bad; the upside of AWD is traction. Acclerative traction, when going in a relatively straight line. On the street, the car feels extremely well planted throughout corners, because you’re never near the limit. On track, that’s only true once you’re pointed where you intend to go. Then you simply stand on the throttle, no thought of modulation in your mind, and off you go. Fast. No need to worry about oversteer, or traction limitations, because with all four wheels clawing at the ground, it doesn’t matter, the car is going to move forward. It’s perhaps too good, actually. I don’t know how much HP you’d have to have to need to worry about corner-exit traction, but 450HP is not an issue, even on street tires. My tires were smoking out of every low-speed corner, but the car just went on its way, oblivious to the cornerworks enjoying the show.

In any case, eventually, by going slower and slower on low-speed corner entry, I was able to get down to a 1:59.1 with a bit of traffic, and that, as they say, was all she had. I was pretty disappointed with the times, and am sure I could have gotten into the 1:58s with some clear laps, but the F465, in particular, seemed determined to make sure that didn’t happen.

So, I started thinking about how to counter the undsteer problem, because really, tracking the car as it was wasn’t so great. It was the most point and shoot car of any I’ve driven. Believe it or not, the Jaguar X-type (awd) I drove at Sebring didn’t have nearly this much understeer. Part of that is probably down to power, however. In any case, I needed more front end grip, so I went looking at the different sizes available in the Hankooks. My choices were 235×18, the same size I had on the car in Michelins, or 265×18. The 265 is 1.1 inches wider in the tread than the 235s. That should do it, but there’s one problem: I don’t have an extra 1/2″ of space between the current tire and the fender. A quick check on the Michelins confirmed they’ve got the same tread width as the Hankooks, so the decision was made for me: it would have to be new Hankook 235s. I’ll be back on the same config at Cal Speedway in November, and I damn well better be able to drop 2-3 seconds.

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