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build diary April 10, 2006: Track day! First, there was time for a bit of setup. After leaving the alignment rack, I put the car on the scales to cornerweight it. This went fairly easily. The end result had a 20 lb weight savings from last year, but more weight on the light right front wheel and a nice 45/55 weight distribution. Just what I'd hoped for with the battery relocation. An interesting thing happened though. I was finished with the scaling when I noticed that the right rear tire was very low. I'd forgotten to set my tire pressures before scaling. The left front was the one that had been flipped on the wheel and it turned out to be quite high. By adjusting the pressures, my cross weights went from 50.5% to 49.5%. This let me back off on the adjustments I'd made a touch and left me with the ideal 50% cross weighting. I also took some time to install the wiper wheelboxes - more on that in a future update. On to the track. There's always a bit of chaos at this particular organization. At least, there was. I hadn't been to the last couple of days run by these guys and they've become much better than before. Unfortunately, a snafu meant the transponders hadn't been charged so we had to wait for a while before timing started. It's a bit of an odd setup. Due to the size of the track, only four cars run at a time. You get an out lap, three hot laps and an in lap. Then you line up for your next baby session a few minutes later. The Seven felt strong. The first session, a heavily modified WRX pulled out on the track in front of me. It was driven by a friend who's usually pretty close in lap times. Well, he miscalculated. By the time we'd been around a couple of corners, I'd glued myself to his tail. He couldn't escape in the corners, under braking and - surprisingly - under power. It was pretty obvious that the Seven had too much rear roll stiffness so I removed the rear sway bar after a few laps. That helped although I still had corner exit oversteer. Of course, some of that could be the result of 145 hp trying to deal with only 400 lbs on each driving wheel. The problem with bottoming out the rear was completely gone and I was still able to drive over berms without any concerns. A slight softening of the rear shocks and the car felt nicely balanced. My boss Bill showed up late and he could tell just from looking at the car that it was moving fast. The body roll that's plagued me for so long was gone. It felt pretty good but only the transponder would tell. Well, if I managed to pass sound check that is. My new muffler is no quieter than the previous one according to the sound meter although it sure doesn't sound as loud. I went back out with my little Supertrapp tip on...and it made no difference. Well, no wonder. It had fallen off on the first corner! We found it, stuck it on well (I'm not sure if it's going to come off now actually) and I was given the green light. Phew! More entertainment came from the throttle cable. Coming out of turn 1, I noticed I'd lost my throttle cable. No problem, I knew it had just popped off the wheel I use to turn it 90 degrees. But why? I idled into an access road, pulled off the hood and restrung the cable. Now the throttle was stuck wide open! I managed to unstick it and drove back to the pits at 2000 rpm. After a bit of investigation I found that the throttle position sensor I was using was binding enough to prevent my throttles from closing properly. Odd, it's been on there for a while. No matter, I wasn't using it anyhow so I just removed it. Ah, finally. The transponders showed up. We stuck one to the back of the Seven and I headed out. I didn't feel very smooth and figured I'd just run about 1:06 on my laps. To my delight, the time was a 1:04.630 with another to back it up! I was ecstatic. A new lap record for "not a kart" vehicles at the track! Next session, 1:04.301. Not bad, I was shaving some time off. While kicking around between sessions as the drifters covered the track with rubber (this is difficult to ignore as a car guy because it sounds like a constant accident!) and dirt, then swept off the dirt, Bill borrowed my new tire pressure gauge. He compared it to our tried-and-true Longacre one and discovered it was about 5 psi high! Hmm, that means my tires were currently at about 13 psi cold. Not ideal. We didn't have a temperature gauge so I'd simply been driving. I added 5 psi to get to the range I wanted and headed out for the next session. The car felt really good, with almost no tire noise and a more stable behaviour. I came in unsure. Was I simply feeling better or was the car actually faster? I knew that I'd been much smoother. The word came in on the radio - 1:03.777 with a following 1:03.8 to back it up. Much rejoicing in the pits from everyone! I went back out for a final set of laps and came back in with a 1:03.368 and a backup 1:03.439 and 1:03.582. Since my goal had simply been to match my earlier 1:05.585, you can imagine how happy I was to take over 2 seconds off. As far as I know, only one other car has only managed one lap below 1:06. There will be some competition when Skip Cannon shows up this summer with his 275 rwhp Caterham, but for the time being I'm very proud of my little toy. Most importantly for my own skills, I'm very proud of the consistency. One of my competitors came over to let me know that I had to watch my back, he'd just pulled a 1:07. This was still 2.5 seconds off my pace at the time and his next fastest lap was a 1:09. True, when it comes to lap records it's all about That Single Fast Lap, but it's a faster driver who can consistently turn the same times. Bill took the Seven out for a few laps and complained about fuel starvation in some corners. He also mentioned the brakes weren't too impressive. He'd been driving the 2006 MX-5 which has aggressively servoed brakes and amazing stopping power, so I didn't think too much of it. I packed everything up in the car and jumped in to drive home - and discovered the brake pedal was super-soft. The front master cylinder was dry! Some feeling around showed a bit of a leak under the cylinder itself. I'll have to investigate that tomorrow. I drove home on the rear brakes and compression braking. I own an old Land Rover so I'm used to bad brakes. I also only managed to put 3.5 gallons in the fuel tank. Hmm, maybe those baffles didn't work so well after all. So, after all that, how's the car? A couple of small problems, but I'm ready for Car and Driver in terms of performance and setup. The Seven rides like a Miata with performance suspension on the street and is a total riot on the track. The engine feels good and strong and the car is at the peak of its handling so far. I'm a little sunburnt, bruised and tired, but I couldn't be happier. entry 1188 of 1439 |