Track Day 35 - The Ridge with SCCA Track Night In America - New Z06 Trans!
The leadup to this event was an absolute whirlwind. With the Transmission starting to have shown issues the track event before, I didn't want to come to this event with a tranmission I knew I was wearing out... so I decided to do a transmission swap. This was of course a very amibitious idea to tackle.
I was able to source a C5 Z06 transmission in pretty good condition for the fair price of $1500 from a local Auto Wrecker, All American Classics. It was a bit of a gamble as I couldn't confirm the condition of the transmission but it at least visuall was vastly superior to my C5 transmission. I proceeded to remove and install the transmission and I won't bore you with the specifcs incase you aren't terribly interested. One thing I'll note is that I will definitely speak to the transmission gearing differences between the Z06 transmission and the base model transmission.
Another probolem I discovered along the way was that my EBC SR-11 rear calipers were toast. They had worn out long long before the fronts, and had even gone to barely being metal on metal. I emailed with KNS brakes about this and we determined that the pad material in the rear was substantially thinner than that of other brands, and especially over that of the front brake pads. Consequently, the pads wore out really fast. KNS was kind enough to send me some replacement pads, but as they wouldn't be here in time for the event I just chucked on some Semi-Metallic street pads to get me by for the event. How much could it really matter anyways, rear brakes are 80% of the braking right? Foreshadowing...
How the Event Went
(Photo credit: https://www.myhrecreative.com)
So I was working on the car right up until the very moment I loaded it on the trailer and drove to the event, which in turn meant after a few moments of traffic I was running too late to catch the first session. Ah well, such is life. Fortunately, dropping into the second session everything went great and I stopped worrying about the transmission at all after two laps.
Gearing wise, I actually think there are some merits to the C5Z06 transmission. I wrote about the diferences in depth over in the article on transmissions, but in short 3rd and 5th gear are a little shorter. This actually worked really well for me, as I was able to stay in 3rd in more places instead of drop down to the notably more torquey 2nd gear. I'd then save an entire shift on straights where I went to 4th, resulting in improved top speeds on the following straights. I also noticed I could grab 5th without feeling like the car fell flat on it's face like it did with the bigger jump of the base model ratio. So, there were improvements, but I had to get used to the differences and adjust my habits to fully take advantage of them.
As much as I say there were some improvements, I did turn my personal best of a 1:52:52, which is a new personal best by quite a few seconds. You'll see I turn a few back to back 1:54 laps, so I was definitely scooting a bit faster than my previous best on average, and then dropped one fast lap. Makes sense as well as when I was leaving another quite good driver in their current Camaro said they were trying their damndest to catch me, which says a lot as I believe The Ridge to really favor horsepower.
Data wise, I was struggling yet again with my Track Addicts setup. I really need to come up with a dedicate setup with my old Android Phone and the bluetooth GPS unit where I can just leave it attached in the car. Still, with the data I got in my first session's best lap of 1:55.446, you can see my top speed is 132.2mph, up from 128mph before. I definitely improved top speed with this combination. I also think there's some extra speed left on the table, as removing the rear tub from the Corvette felt like it introduced some lift and drag on the rear of the car, resulting in a noticably looser feeling rear end. That said, it did let me rotate the car more, and I would in general find I get higher lap times at the end of a session when my temperatures rise and I'm better able to rotate the car.
Now is also a good time to mention those semi-metallic brake pads I chucked on the rear of my C5 corvette. Braking power was decreased SUBSTANTIALLY and I had to adjust all of my braking zones because of this. Where before I could stay on the accelerator longer and carry deep into the turns, I'd find myself rolling off the throttle sooner and starting to brake about 30-50 yards earlier. So I am also leaving time on the table there as well.
Things I'm thinkig I'll modify in the car next:
- Fix rear compartment drag situation, hopefuly improving things there.
- Possibly get around to changing out the intake manifold and the oil pressure sensor while I'm at it.
- Maybe get around to ditching the Air conditioner stuff up front along with the air pump to further reduce the weight of the car... but that seems like a lot to fit in before my next event.
- Figure out a better cell phone mounting and track addicts setup so I am not just duct taping my phone down inside the car before each session.