Z/28 at Thunderhill 5-Mile

[brt3]

Spent a great weekend at Thunderhill -- and this time the highs were in the 70s and 80s, instead of 105 degrees like last time. I am still learning the track, but got my time down to 3:40. My camera kept freezing, so the second and third laps in the video are 3:44 and 3:48. Had a blast; this car is MEGA. It continues to attract a huge amount of attention; people really seem to love this car...

Video is here:

[its a syn]

That was one of the best videos of the Z/28 to date. Thank you!!

[jim911]

nice video, best yet

[Foxrus14]

Can anyone drive on this track or do you need an SCCA license?

[ba2ss]

Sweetest video!

[backtotintops]

thanks for the vid...that's a very challenging track!!!...nice driving!

[brt3]

Originally Posted by Foxrus14

Can anyone drive on this track or do you need an SCCA license?

Most HPDE events have various groups, from beginner to advanced (open passing) -- competition license not required. Hooked On Driving is all over the country (not in TX, yet), and they had A (beginner), B (intermediate, with point-by passing only in designated areas), C (advanced, with open point-by passing), and D (open passing) groups. I run in C, because I don't trust all of my fellow human beings well enough to run in D with open passing...

[brt3]

Originally Posted by backtotintops

thanks for the vid...that's a very challenging track!!!...nice driving!

Thanks for all the positive feedback. One thing I've realized with this car is that it's all too easy to switch off the brain and go into Hooligan Mode. The car has such high limits and is such a blast, but over-driving the car is slower and -- more importantly -- hard on the tires. Which means $$$$ instead of $$...

The crux of this is the weight of the car. Even with those massive contact patches, the brakes are so brutally strong that you can overpower the tires. The final turn on the new (west) circuit has a short straight where you pop over a crest, go downhill, and have to brake hard to make a 90-degree right onto the old (east) circuit.

I was playing with a GT3 and was amazed by how I could really close on him in this area. I was braking later and later, and shortening the braking window by really slamming on the brakes. I got to the point where the tires started slipping and chattering, and at that point I went back to really paying attention to transitions in order to be smoother.

I find heavy cars are a little more like dancing. You really need to think ahead and set the rhythm for the car to follow. Simple actions -- like easing off the throttle to give the fronts a little more bite on fast sweepers -- really seem to make a difference. Slow in, fast out is how I prefer to drive the Z/28.

Guy Gamba of OnEdge Performance is always on hand, with a full crew, at most Hooked On Driving events. I think Guy has forgotten more about tires than most of us ever knew. He uses Pirelli Trofeo Rs on his daily-driver BMW, and he really knows the ins and outs of this tire.

One of the services Guy provides is a full check after a session, with pyrometers and tire gauges. I've included the two checklists I received on Sunday. You can tell that it got cooler as the day went on; we even had a smattering of rain.

Guy was hugely complimentary about the car and could tell, from the temps and pressures, that I was driving the car smoothly. I won't say well as I'm still learning the car and building my confidence in its limits, but it felt great to me. He also said that the tire chart was exceptional for the Thunderhill 5-mile track. You can see, from the videos, that there are some extreme loads going on, and not many places where the car gets a rest during a lap.

Look at these numbers. All about the tires? No way. This really shows how Team Z/28 designed the car to function as the sum of its parts. From the photos above you can see how well-controlled the MultiMatic shocks and suspension are. On my car each corner has 6+ less pounds to cope with, because of my custom wheels. When driven just under or at the limit without aggressive control inputs, the tire temps are remarkably even.

After playing with the tire pressures, I can attest that 32 psi seems to be the magic number (at the tracks and conditions I've driven) for the Z/28–Trofeo/R combo. IMHO, of course...

[brt3]

One more thing...

As I'm reaching the limits of the car, I'm realizing that a harness is mandatory for track usage. Under maximum braking there is simply no way to avoid bracing yourself with your legs, feet, arms and hands. I have no doubt, after this weekend, that this compromises control. I realize there are mixed feelings about this, but I think I'll be placing an order with Brey-Krause this week...

[ZL1-V]

Thanks for sharing! I haven't been on the track yet with my ZL1 but in the past with my other cars and motorcycles and track days, I always remember what the instructors and drivers said to me. Start slow and learn the track first, and the speed will come later. Looking at your video you are indeed are a smooth driver. It is just difficult to become "one" with the car in the beginning. If that makes any sense?

[brt3]

Originally Posted by ZL1-V

Thanks for sharing! I haven't been on the track yet with my ZL1 but in the past with my other cars and motorcycles and track days, I always remember what the instructors and drivers said to me. Start slow and learn the track first, and the speed will come later. Looking at your video you are indeed are a smooth driver. It is just difficult to become "one" with the car in the beginning. If that makes any sense?

Yes -- perfect sense. Initially you're feeling around learning the limits of the car. On a new track, for me at least, you're learning the scary bits slowly -- and trying to make up time and push the car hard on the parts you know (or that are easier to figure out). So there's that tendency, when on track with other cars, to overdrive a bit to catch or pass the cars ahead.

Balance. The "B" word. This is starting to sound a little too "Kung Fu", eh? "The grass blade blows in the wind; it bends yet does not break"...

[45thAnniversary2SS]

Nice lines! Looks a little lonely way up in front there lol.

[ZL1-V]

Originally Posted by brt3

Yes -- perfect sense. Initially you're feeling around learning the limits of the car. On a new track, for me at least, you're learning the scary bits slowly -- and trying to make up time and push the car hard on the parts you know (or that are easier to figure out). So there's that tendency, when on track with other cars, to overdrive a bit to catch or pass the cars ahead.

Balance. The "B" word. This is starting to sound a little too "Kung Fu", eh? "The grass blade blows in the wind; it bends yet does not break"...

It is in way it is somewhat connected to the mind. I'm sure you have experienced this at the tracks you have been on? The ones where when you are sitting and waiting and you can close your eyes and go through every turn and know where the bumps and irregular surfaces are on the track.

[Toronto LT1]

Thanks for sharing.Nice driving and your car looks badass! Are those the stock Z28 rims,you're running and how much for a set those massive Trofeo tires? I hope you don't mind all the questions.