Targa Miata
March 25, 2009 - A great weekend at Laguna Seca.
I drove out to California expecting a two-day track event, and ended up with quite a bit more than that.
Of course, there was a big track event. The Targa car spent around 7 hours on the track. I was playing with the fast guys in the A group. The open passing and chance to play tag with some of my friends in close company made the track far more interesting. Partway through the first day, circulating alone, I was sick of the same 11 corners over and over. But once I got into a chase with a few others, it added a whole new dimension. I can see how wheel-to-wheel racing could be addictive, although it's a different sort of game from the open road. I did notice that my peak speed on the track was only about 160 km/h.
During the Targa, our top speed on the Leading Tickles stage was 190 km/h. With trees and rock walls lining a bumpy road that we'd never seen before.
In the rain.

The car was handling perfectly. I'd nailed the balance with the new springs and sway settings, and I didn't touch the setup all weekend. When my good friend - and ex-pro driver - Rick Weldon took the wheel, he came in laughing and completely in love with the car. He didn't want me to change a single thing. It's good to get his stamp of approval, as it's always a bit worrisome to think that maybe I've adapted to the car instead of getting the car right. He really felt the car was prepared well and the handling was bang-on. Another fast driver commented on how it was impossible to get the car upset. No matter what I did, the car just ate it up and came back for more. Naturally, this seemed to be in context of my habit of making full use of the berms. "The track is wider for that car", one other driver noted. The hearty engine came in handy as well, even holding off at least one turbo Miata down the long front straight. Rick went out with Tom Matano in the passenger's seat of my car and got into a big scrap with one of his Spec buddies, everyone coming in with big grins.
Janel was also there, getting friendly with the driver's seat on the car. It was the first time she's really had the car up to temp and she was much happier than she had been at our little kart track day a few weeks back. As soon as she discovered how well the brakes worked, she started using them in earnest - she's always had the habit of coasting up to corners, so that's a big step. And more importantly, she discovered that all that information coming from the car is useful. As she described it to someone else - her Miata will do the same thing whether she takes a corner well or takes it badly, but not tell her. But the Targa car will let her know if she takes a corner well, giving her the feedback to improve. She can feel the tires working. She figured out turn 10 almost immediately, and I worked with her over the weekend to take what she was doing on that corner and apply it to others on the track. We worked our way around piece by piece - 6, then 4, then 5. It turns out she likes fast corners best. The Corkscrew wasn't her favorite as she had to muster the nerve to go over that blind drop. On her last session, she went out with Rick and he managed to coach her best driving ever out of her, including figuring out the Corkscrew. She was overjoyed and Rick was bubbling over with praise about how well she takes instruction. She's got a good feel for the car, and after this weekend I think she likes the driver's seat almost as much as the navigator's! She was nervous that Rick would be disappointed, but it was the exact opposite. Was I proud? Oh yes.
The only downer to the weekend was that, in a remarkable and extended spasm of incompetency on the part of US Air, she arrived 24 hours late and our planned mini-vacation in Monterey didn't happen. We'll be avoiding that airline in the future.
There were lots of fans of the Targa car there. I don't think Janel ever believed me about how many people know about the car and followed our race, but she got a chance to see the enthusiasm first-hand. Thanks to everyone who came up to introduce themselves! I was also surprised at the banquet on Saturday night when I was honored with an award for my contributions to the Miata community. Wow!
The car saw about 7 hours of track time. It was almost perfect, with only a couple of hitches. The first happened when Rick was driving the car, the check engine light came on and the car lost power. That's the Hydra Nemesis dropping back to the safe spark map to protect the engine. I haven't been able to figure out just what happened there, although the fuel level was getting low. I tossed in a bit of gas and some toluene (causing some real confusion in the pits, seeing as how I was pouring it out of a paint shop can) but the problem happened again. A full tank of 91 "competition" fuel and it cleared up. Weird. I'm going to change the fuel filter, as I don't know what's gone through that tank with all the small Newfoundland stations. Then, in the last couple of sessions, the high-rpm stumble from the last day of the Targa came back. Again with the puzzling problems! I'm going to brainstorm this one with my coworkers for a while and see what they say.
I also got the chance to drive Elvis, the LS1-powered Miata I autocrossed a few months back, on the track. Yee hah. The thunderous rampage down the straights was to be expected, but on top of that the rest of the car worked very well. It put down power far better than it had any right to do, and the overall balance was still very good. As it should be, because Elvis was running the AFCO suspension developed on the Targa Miata! When another car pointed us by, we didn't just pass them. We evaporated them. It would be an awesome Targa weapon, with huge acceleration, a wide powerband and the ability to dance in the twisty bits. Unfortunately, it got coolant into the cylinders and the car got parked. The current theory is that the modified heads were ported too far and got into a coolant passage. Whops.
Now, Elvis had been driven to California while I towed the Targa car out. So, other than a quick stop to change to street rubber in Reno (after going over a 7500' snowy pass on race rubber alone at 11 pm!), I drove the race car home without changing a thing. 7 hours on the track, 17 hours on the interstate. I've always said that a good Targa car was a good street car, but I never thought I'd have to prove it in this way. I averaged 30 mpg and 70 mph on the run from Sacramento to Reno, which is nothing to be be ashamed of. How's that for a dual-purpose machine?
entry 663 - tags: Laguna, skills, testing, handling
September 5, 2010 - Whoops.
I figured out what was wrong with the car yesterday. Yesterday morning I'd set the tire pressures and found them a bit low. At one point during the day, I tried pulling a bit of pressure out just to see how it worked. It seemed to get a bit better but I was still chasing the handling.
Just to confirm, I went back to my notes to see what the hot pressures should be - and I'd mistakenly set the cold pressures about right for the hot pressures! Even better, it was cool that morning and the day got pretty darn hot - up to the mid-90s. So that explains what was going on. On the first, relatively cool session I was probably pretty much dead on until the tires started to take temperature. And my second lap was the fastest. On later ones, as the track got hotter and I started taking more aggressive warmup laps to get heat in the tires, they were getting badly over-inflated.
I've dropped the pressures down to my usual track starting point now. We'll see how well it does at the track this weekend. I suspect much better! Boy, is my face red.
entry 762 - tags: tires, handling
August 10, 2011 - The FM Summer Camp is the last big event before the race.
It's a chance for us to show both Targa cars off to the very people who made it possible for us to go to the race. In the process, the cars spent two days pounding around the track giving rides. This works as a nice shakedown too!
Nancy, the 2006, did quite well. The car currently has more grip than power, but is nicely adjustable in the corners if you carry some speed in. It's got a good tossable balance. The flat torque curve isn't super-exciting, but it does get the job done nicely.
The Targa car is under-tired on the 140 treadwear Toyo R1Rs. It is quite likely they were overheating with the frequent 6-minute sessions and very hot temperatures, as they did feel best on the initial lap. I played around with pressures to see if I could improve things, but overall the car was just not as well connected to the ground as I'd like. The biggest complaint is the turn-in softness, which was really brought into sharp focus when I jumped into the other V8 car with Nitto NT-01 R-compounds. So, given that I wasn't going to set any lap records, I spent the day provoking the car to see how it would behave under duress. I was putting wheels on berms, braking with the car unbalanced and generally trying to make it misbehave. And the car was being the usual excellent platform and just letting me do whatever I wanted.
The car has a bit too much oversteer. This is partly because I was fooling and using wheelspin to rotate the car, but also because the rear spring rates are currently too high at 450 lbs. I have a set of 400 lb springs on my desk at work, and they're going in the car today. That will let me run a rear sway bar, which gives me a few more options for tuning the car's handling. At the moment, I can choose between just a bit of oversteer and way too much oversteer!
The car wasn't perfect. It ended the first day running on 7 cylinders. It's done this before, and last time I fixed it by reseating the plug wire. This time, it simply looked like weak spark. I suspect the coils on the car are from the 2002 Firebird that donated the heads, so I picked up a new coil for the dead cylinder and dropped it in. Voila, problem solved.
Near the end of the second day, I felt a clunk from the front and my steering wheel changed position. One of the new alignment cams had shifted under hard cornering and braking. The change in camber had also changed the front toe, thus the cockeyed steering wheel. I should have seen this coming - the cam is in the new control arm, which is covered in nice slippery new powdercoat. That's easy to fix and to avoid in the future, and exactly the reason why I test like this. I tried a couple of times to eyeball it back into the appropriate position, but couldn't quite get it right. So I called it a day and parked the car.
Overall, a good weekend. As a shakedown, it worked very well. It's a shame the Targa Miata ended the day parked in the trailer early amidst rumors of breakages, but it was nothing serious so there's no harm done.
Now we're about 3 weeks away from departure, and I still have a big list of things that need to be done. It's time to get cracking.
entry 901 - tags: testing, suspension, Nancy, handling