Thursday, April 26, 2012

Would ya shut up about the stupid wing already?

I will, I promise. But this weekend I'll be at Summit Point, and they're calling for rain.  Rain seems to be the hallmark of the 2012 NASA Mid-Atlantic season so far, and one thing that's become blindingly obvious about the wing is that it's amazing in the rain (last month I ran similar lap times in the rain to what the racers ran--on slicks).  So dialed-in or not, it's staying on and may even end up with a pretty aggressive angle on the wicker bill.

I may not be excited about the weather or the incredibly small pool of competitors, but I'm pretty confident about this weekend.  Let's go to the track!

Thursday, April 12, 2012

A confession, of sorts

When I sourced a wing and a differential for this season, I didn't do my homework.  So often I've gotten away with either getting things right on the first try, or learning to compensate. So I let hubris guide my hand and just mounted the wing, figuring it would just work and I'd be faster. Whee!

Well I'm not.

And now, fully 3 months after putting the thing on the car, I'm reading and learning about how wings work. And the chances of "getting it right on the first try"? Incalculably small without doing some very complex math and having access to a wind-tunnel.

I learned after the first time I used it that the wicker bill was set too steeply, but only dialed it back to 50% in order to keep the downforce. I had considered dialing it all the way down for Summit Point, but now that I know a teensie bit more about How Things Work, I'm thinking I might be better off removing it outright.  I'm also learning that the angle of the wing, though it looks flat, may actually be entirely too steep.  It certainly becomes too aggressive with the wicker bill, which has a mathematically enormous planform at 3.375" chord * 56" span. That's too much for a Miata, IMO, unless I'm just using it for autocross purposes.

So my rant from the other day about removing the wing and building a diffuser...not gonna happen. Further research shows the Miata's rear pressures zone just isn't big enough to benefit from a diffuser, and the car's likely too high off the ground anyway.  Any reduction in lift would be insignificant compared to the points-penalty assessment.

Aero is difficult and confusing. Were it not for the dramatic and easily-observed impact it's made in my braking, I'd ditch it entirely, but I know there's more to it than just looking bad-ass. And I know that getting it right will produce good downforce with minimal drag. I just hope to get it right(er) this season.

Tuesday, April 10, 2012

NASA March Madness @ VIR

My lap times are going the wrong way.  Call it fear of aggravating my appendectomy wounds, call it fear of the damp conditions, the result is the same: I'm getting slower.  And data is telling me something I really didn't want to know.  It's the wing.

In February, I set an aggressive angle on the trim tab because I could only get the foil to go flat, even at max elevation. This was due to the slope of the trunk and limited adjustment options on the wing itself. I couldn't get the car past 114, which was off its previous best of 118mph and clearly not working.  So I dialed the tab back to 50% and got a little better performance without losing grip.  But I'm still almost 2 full seconds off last season's pace.

I adjusted shift points, drove harder through South Bend than I ever have before, and took 3 full seconds off my braking PER lap.  The car rockets up to 90mph like it's been shot out of a cannon, but hits an aero wall.  Acceleration graph comparisons over distance show a dramatic fall-off at 90, so it's clear I need to dial that trim tab down even further, but I don't know that it will be enough to keep the rear end planted and regain any time.

In spite of the high 2:21's, though, I was still able to eke out a win both days, finishing just 0.3 seconds ahead of second place on Saturday, but cementing a firm lead on Sunday before the rain ruined the afternoon.

Overall it ended up being a very good weekend, and I have to thank Hoosier for their generous contingency policies, but it's clear I have some work to do to get the car to go fast again.

I'm currently debating replacing the wing with a rear diffuser and going back to my beefier sway bars.  The stock ones do not feel planted at all, and they're much noisier when pushed to the limits.

Monday, April 09, 2012

In which I have surgery and a wreck

Three weeks ago (hard to believe it's already been that long), I got up nice & early on a Sunday morning to get the family ready for church. I fed the boy and went upstairs to get dressed, but just wasn't feeling quite right. I tried waiting it out, but it just got worse and worse.

By 10:30, it was clear we weren't going to church. I felt like I'd swallowed a ball of hot glass shards. I sent myself to bed, but didn't sleep. I migrated to the sofa to watch all the racing on TV, but couldn't even focus on that. After 4 hours, the pain hadn't moved or abated at all, and I'd tried to vomit. While successful, it did nothing to alleviate the pain.

Off to Patient First I went. PRO TIP: don't go to Patient First.

I waited in the lobby for an hour, then was told to stand upright on the scales. I couldn't, but that didn't mean I didn't have to try. After another 50 minutes of waiting, I was told that while I may have appendicitis or pancreatitis, I probably just had the "stomach bug" and should either go home or to a hospital for more tests. Yay Patient First! 2 hours lost!

30 minutes later I was sitting doubled-over in the ER waiting room at St. Mary's with my wife and son, who was terrified that I was dying right in front of him. By 6:30pm I was in a treatment room, and my parents were on their way to take Alastair for the night.

By 9:30, I was no longer in any particular pain, though there was some tenderness in my abdomen, leading the medical team to believe that I was facing appendicitis, but they wanted to run some more tests. X-rays were done at around 10:30pm, and a CT scan at 1:30am confirmed it: appendicitis. God bless her, K stayed for the whole shebang. I sent her home twice to let the dog out, and had to force her to go home for the night when it was time to get moved upstairs to my more permanent room.

At 7am, I got a wake-up call from the surgical staff telling me that I was going to have an appendectomy. Up until that moment, surgery had been one of my biggest fears. But having not been able to keep any food or water down since 10:30am the previous day, all I cared about was getting medically fit enough to drink a glass of water. Nothing else mattered to me (well, except whether or not I would get to go racing that weekend, but more on that later). I went back to sleep, and woke up with K by my side. We had a couple of visitors, and at 10:30 the doctor came back to tell me that I was either going to have surgery at 11am or 1pm.

20 minutes later they were wheeling me downstairs to the OR, joking with me about delicious foods I was in no condition to eat.

I remember being in the prep room for about an hour, listening to an elderly fellow become increasingly hostile to the medical staff because he hadn't bothered to keep track of his own health. Then they came for me, and I woke up groggy in a recovery room. This surgery stuff is apparently quite easy.

I got to my new room in the surgical ward and drank. Oh how did I drink! And I ate Jello. Quite possibly the best thing I'd ever tasted in my life! A couple of hours later I took my first tentative steps, and through the night got up repeatedly to walk around the ward, my wife ever at my side.

And then, the next morning, with no fanfare at all, I went home. And that was it. Of the percocet I was prescribed, I took only 3, waiting for the pain to double me over, but it never happened.

By Thursday I was out hitching the trailer and loading up for a weekend at VIR.

All of this sounds very uneventful until you consider that my actual plan was to climb into a race car 5 days after surgery and try not to kill myself. In the rain. On slick tires. Oh, and I would be instructing, too...riding in some person's car whom I'd never met and hoping that they'd also not kill me in the rain. I'm genius.

As it happened, getting into and driving my own car was no big deal. The rain let up and I got a little brave late in the first day, eking out a 0.3 second victory in my class, and having a great, if wet, time in my student's car.

Sunday, however, 6 days after surgery, I had my first ever wreck on track. My student misjudged his entry into a turn, tried to correct mid-turn, and didn't quite succeed. Off we skated into the grass, straight at a tire wall. Realizing the belts were directly on top of my still-healing wounds, I sank down in the seat until my knees were resting on the dashboard and waited for it. The hit honestly wasn't bad. There was no pain, no blacking out, not even a significant whip of the neck (no HANS). When we got back to the pits, it was evident how lucky we'd been: no structural damage to the car, and the airbags didn't deploy. So we couldn't have been doing more than 10mph or so. I got lucky.

And the best part? I won that day, too.

Oh, and I didn't die in front of my son. Hopefully that will make it clear to him that it's possible for someone to go into the hospital and come back out alive, healed, and capable of resuming a normal life.