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 | |  | April 14, 2010 - New videos have been uploaded!
There's a video of Janel's fastest session on Friday as well as a couple with me driving in the middle of a fairly entertaining group. Videos
On Saturday, the event organizers gathered a few of us together for a video shoot. There was a hand-held camera in one of the cars, and the rest of us were basically tasked with putting on a good show. Two Spec Miata drivers and a couple of modified super Miatas - and my little rally toy. I was probably the least experienced track driver of the bunch, so I had to pedal pretty hard just to keep up! The extra horsepower of the Targa car let me reel in the Spec Miatas most of the time, but not always.
Still, it was like a little race. One of us would take the lead, then allow someone else to pass. Meanwhile, the camera car was zooming back and forth. I certainly wasn't the fastest driver or car in the group, but I consoled myself with the thought that if there was a speedbump in the middle of the front straight, I was the only person who could take it at full speed!
The Targa Miata is one solid little car. This picture was taken after Janel ran for a full day on Friday, and then she and I both drove the car on Saturday. On Saturday, the car was on the track for 20 minutes, then parked for 20 minutes before it went out again. And that's the state of one of the tires. A tire that we used in the Targa. A week long race, followed by a bunch of local track days, followed by two days at Laguna Seca last year, then repeat the local track days and two more days at Laguna. And it's only about half worn! Amazing.
entry 750 - tags: play, laguna seca, video | | |  | April 25, 2010 - Some pictures from the Laguna event.
More are coming. This is the first session on Saturday (it must be, I'm not wearing my driving suit) and that's John Anker coming down the Corkscrew behind me. He was never behind me for long!
Photo by Mark Booth.
entry 751 - tags: laguna seca | | |  | April 25, 2010 - Mark got a this great shot of Janel at speed.
I'm not sure where it was taken - it's a right hand turn, so I'm thinking it's either turn 4 or 10, and something it telling me it's 4 - but I really like it.
Photo by Mark Booth.
entry 752 - tags: laguna seca | | |  | April 25, 2010 - A shot of our video session from outside turn 2.
I'd just steamed by the whole group on the straight (with their acquiescence, as there's no way I could power by a couple of those cars), and was taking a wide line into 2 to let that Spec Miata run inside me for a cool pass. The camera is in the red car about halfway back. This was fun stuff. The photo was taken right at 2:00 in this video.
Photo by Mark Booth
entry 753 - tags: laguna seca | | |  | April 25, 2010 - Laguna Seca is a pretty track.
Quite a change from the dusty desert. Here's Janel about to dive over the edge into the Corkscrew. Photo by Got Blue Milk.
entry 754 - tags: laguna seca | | |  | May 1, 2010 - More magazine coverage!
The June 2010 issue of Grassroots Motorsports has a good article on our Targa adventure. Not just the story of the race, but also some sidebars on how to survive your first performance rally, details on the car and what it's like to run an event like this with your spouse. Thanks to Grassroots for the attention!
If you'd like a free copy, they're happy to send you one. It's a good magazine, even the issues that don't have a mention of the Targa Miata in them.
Get a free copy
entry 755 - tags: magazine, grassroots, publicity | | | May 13, 2010 - The 2010 Targa factors have been released!
This has been a long wait, and I think it's because the organizers have been making sure their fairly major change is correct. Basically, the event is now split into two.
The classic cars (1981 and older) continue as-is. The Level 3 preparation level is expected to be dramatically faster than Level 1 or Level 2, and I think that's to be expected. Level 3 is aimed at the cars that are taking full advantage of four or more decades of hard-won competition knowledge, and are basically new cars in a vintage shell.
The big change is in Modern: there are no more factors. In other words, Modern is a full-on race. I expect the base times to be fairly aggressive, which means that many penalties will be taken. The fastest car will win. Awards will be given for the five classes, based on age range. There's no mention of any distinction between preparation levels, so basically everyone will build for Level 3 preparation. The Targa Miata is a Level 2 car other than the fact that it runs a 1999 cylinder head. If I installed a 1994-97 head, it would be fully legal in Level 2.
But since there's no handicapping, why not run in Open? Instead of competing for class honors with big-engined Level 3 cars of similar age (1991-97 in my case, which means a whole lot of rally-bred Subarus and Mitsubishis), run for the overall win with the big boys and throw away most of the rulebook.
That's what I would do if I were building from scratch. I'd stuff in that big V8 and proceed to scare myself silly. I might not be competitive at the top level due to my driving ability, but the car would be a real beast to drive and a massive rush.
The smaller cars won't be in the hunt for an overall win and probably not even for a class win. Minis, Civics and Miatas will now be racing for fun. But you know what? These cars wouldn't be racing for an overall win in any other race event either.
The biggest problem I see with the Modern setup has to do with the trophy times. Any novice team sets themselves the target of winning a Targa plate. The trophy times are set based off the target time for the stage - I think it's about 40% slower or so. It's an excellent goal. But without different factors for the different classes, that 40% of the target time is far more difficult to hit with the slower cars. Faster cars will have an easier time. The Targa plate (in my mind) is meant to be a test of consistency and reliability. This change will put a much greater emphasis on speed with the slower cars.
Of course, it's easy to poke holes and not offer a solution. The only alternative that comes to mind is to scale the trophy times off the fastest car in a particular class. For example, the trophy times for Early Modern for each stage will be set at 40% of the fastest Early Modern car to finish the stage. It means they'd have to be calculated after the stage is finished, but that's not a big problem with automated timing.
I'm hoping this change will attract more monster cars to the event, now that they no longer have to worry about explaining how they lost to an old BMW.
Targa factor announcement
2010 factors
entry 756 - tags: factors, 2010 | | |  | May 16, 2010 - Road trip!
The big Miatas in Moab event took place this weekend, and I headed down to say hi. It's only about 75 minutes from my house to the lodge where the event was based on Saturday. The crowd at this event is almost the exact opposite of the folks that were at Laguna Seca a month ago, and the race-scarred Targa car did stand out. Most of the attendees didn't have roll bars, and nobody else had brake dust on their wheels, well-scuffed race tires and a cage! Still, there were a lot of fans of the car and it did get a lot of attention and I spent a fair bit of time talking for various Miata enthusiasts from all over the US. I also took a couple of people out for test rides in the newest V8 car - yowza, that's a fast, fast car. As you can see in the picture, the Targa car got the prime spot for the big group photo.
One excuse for this little excursion was to test the dual-spring suspension a bit more. It had acquitted itself fairly well at Laguna, although with a lot of roll. On the highway, it felt a bit odd. The change in spring rates definitely make it difficult to get the damping right - it's either heavily over-damped on small movements or under-damped on big ones. I have it set up for the former.
I did find out where it works best, though. There's one way to get to Moab from Grand Junction that runs across a few miles of abandoned road near a ghost town. It's paved, but fairly rough. And at "targa speeds", the suspension ate it up. I can see this setup working well on Leading Tickles, for example. The car just went supple and absorbed almost everything.
It's not perfect. A really big hit would bottom out the rear hard. Granted, I'm running a track ride height and not a Targa height, so there's at least an inch of travel missing there - but I think the problem is that the secondary spring rate is too close to the primary. The effect is that the secondary spring never really closes up, so the rear spring rate is too low for too long. I'm planning to pick up some new secondaries that are around 150 lbs as opposed to my current 300, and I think that will address all of my concerns with this setup.
It never stops. I'm always trying to make this car better!
entry 757 - tags: Moab, suspension | | |  | July 16, 2010 - I've been working on other cars, and the Targa Miata has been sitting.
"Sure boss, I guess I'll drive the supercharged 2006 at the track day to see how it does" - that was actually a really good track day, as it poured rain. The combination of a powerful car on wide street tires and heavy rain made me work on some skills that could prove very useful at Targa.
But the car hasn't been forgotten. I've removed the 300 lb secondary springs to cut down on that initial body roll and sharpen up the car's reflexes. The radiator was removed as part of some cooling system testing and has ended up in Janel's street Miata. The differential is coming out so we can test a different unit. All of this should be on the track in a bit over a week.
But when I was working on the car, I discovered a problem. I know the Performance Friction PFC97 pads are hard on rotors, and I've been watching the slots on the rotor as a guide of wear. But when the wheels were off for something else, I took a closer look and was shocked. The rotor in the picture used to have slots! The outer face still has lots of meat and isn't showing dramatic wear, but the inner face is completely worn away. Both front wheels were like this. Yikes. I also discovered a cracked rear rotor.
So, what happened? Good question. The brackets on my brakes are from a source that often needs a bit of shimming to get them aligned well enough to clear the rotors, and even then my calipers are off-center on the rotor. I wouldn't think a 4-piston caliper would matter, but the brackets are being replaced with new ones that are perfectly designed and machined to keep the caliper centered. New rotor rings are on the way. Flyin' Miata is also testing a different brake kit that will be on the car for the next couple of track days, so there's no big hurry.
I have new rotor rings on the way to replace these.
entry 758 - tags: brakes, suspension, cooling | | | August 9, 2010 - Now THAT was fun!
Last weekend was the Flyin' Miata Summer Camp, previously known as the Open House. Some may remember that the car made its track debut at the Open House in 2007 - it's hard to believe it's been three years. That time, the car managed a best of 1:07.977. These days, I'm consistently in the 1:04.xxx range on the same set of tires I used in the race.
The original plan wasn't for me to drive the Targa car. After some memorable battles for the lap record in 2008, a decision was made that the staff should spend more time taking customers for rides. I was scheduled to drive the supercharged 2006, which is a pretty fun car. I did get the Targa car all reassembled and bedded the new brake pads in, just in case. I actually ended up using it as transport to get to the track that morning.
It became apparent fairly early on that something wasn't right with the 2006. It had some wiring problems recently due to a poorly installed O2 sensor hardness and we're still chasing down gremlins. The car was way down on power so we decided to park it. I jumped in the Targa car and took people for rides in that instead.
Halfway through my first session, I just started laughing and yelled out "it's great to be home!" This is such a good car. Without the secondary springs I'd been running before, the 600/450 lb setup made the car super-responsive. The balance was a bit understeery (I hadn't had time to set up the sway bars) but the car still worked well and could be easily balanced.
By the second session, I was taking the "AFCO line" through the chicane, actually leaping the inside wheels across the gap inside the corners and probing the limits of the braking zone. In the FM cars, we had to be a bit conservative to make sure the tires and brakes were good and we gave the customers a good ride. But the Targa Miata is like an anvil, and I could push it to the limit without having to worry about anything. It's made to be run hard.
We didn't have transponders on the cars, but it would not surprise me if I'd been in the 1:03 range. The car felt that good, and a number of my passengers commented that I gave them the ride of the weekend.
Oh man, was that ever a good time. What a great little car.
entry 759 - tags: track | | | August 24, 2010 - I spent part of the day replacing the differential.
I'm going to try out a new unit that's a clutch-type instead of the Guru helical I have now. The car's tendency to spin an inside wheel on right turns should be abolished!
Or should I say, the car's old tendency. At the Open House, I didn't have any trouble with that. I always had a passenger which does alleviate the problem - but likely more important, I was running a different spring setup with a lower ride height than usual. I also didn't have the rear sway connected, but I know I've run without it before. Interesting. It could have simply been the passenger and the fact that I've been driving other cars and taking lines that alleviate wheelspin. Anyhow, it'll be interesting to see how this new diff turns out.
I've also pulled one of the front shocks off. Due to an assembly error on my part, it was leaking pretty badly at the track day and acting very poorly on right turns - maybe that was the secret! The good thing is that if an AFCO leaks, you can just refill it with the correct oil and it's as good as new. I have the oil, so I'll top it up and test the result on the track by Sept 4th at the latest.
entry 760 - tags: suspension, differential | | | September 5, 2010 - Track day test!
The good news? The new diff works beautifully. I could get on the power much earlier and get a solid drive off turns - left and right. It's a clutch-type diff. I had an idea this might be effective as the V8 cars from Flyin' Miata have shown an uncanny ability to hook up out of corners. On the first session, I managed a 1:03.796. That's nearly a full second off my personal best in the car. Now that is some serious progress!
It wasn't without a cost, however. I found the handling of the car was difficult. In particular, I had trouble with corner entry understeer. It didn't seem to be there for that first session, but almost seemed to get worse as the day went on. I tried to drive around it and I tried to tune around it with shock settings and a stiffer rear sway. Interestingly, the sway bar change didn't seem to have any effect. I also found I couldn't get enough rear bias into the brakes - even with the rears turned up all the way, I'd still lock up the fronts too easily.
I suspect what might have happened is that the old tires have finally given up. This is the same rubber I ran in the Targa almost exactly two years ago. They've seen 5 days at Laguna Seca with two drivers, probably a dozen track days on this track, some road use and of course the Targa itself. When the Seven is too low on traction, it gets a similar behavior. Oddly, the car doesn't feel slippery, it's just not hooking up the front under braking or turn-in. Am I going in the wrong direction? Hard to say. I might just have been trying too hard.
I have another track day on a big track next weekend, and I flat-spotted at least one of the fronts badly enough that it's done now. I have two more mounted tires and two unmounted ones in the garage. Both pairs from the Targa (or possibly pre-Targa testing) of course, but they haven't seen as many heat cycles. So I'll swap the flat spotted front tires out for the "new" unmounted ones and put the other pair on the rear, then take the existing rears with me as spares. I'm also going to double-check that front shock to make sure it's working as well as bleed the brake system again, and if things aren't any better then I might throw in some extra front camber if possible.
I ended the day a bit bummed out that I couldn't go faster, but I'm feeling a bit better now that I look at the times again. Another Miata at the event - a turbo car running some Nitto 225/45-15 tires on 15x9 rubber!- was putting down times right around the same as I, and his times fell off over the day like mine did.
Was the diff a success? Well, if I can sort out the handling, yes. Right now, the car wouldn't be happy on the Targa because it's too easy to wash out the front end, but if I can get that sorted then it's a real winner in terms of fast corner exit speeds.
entry 761 - tags: testing, differential | | | 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 | | | September 11, 2010 - Track day at High Plains Raceway!
To celebrate scrutineering and odometer check day for Targa Newfoundland 2010, we headed to a new track near Denver to try it out. HPR is a 2+ mile track with a surprising amount of elevation, and I'd heard quite a few good things about it. Not a quick drive from Grand Junction, but not far off Pueblo where I did a lot of the original development of the car.
The day was put on by the Z Car Club of Colorado, and I think they only do a couple of days a year. There was a very complex and ambitious schedule that was broken by the time the driver's meeting started 40 minutes late, but that happens. They were quite safety conscious, so no complaints there.
It took a bit of time to become familiar with the track - there are two sections that look fairly similar, and a number of blind spots. But after a couple of sessions, I was up to speed pretty well. The sessions got longer and longer as the day went on, and my last time out was a full 30 minutes. I was only going to do a portion of it, but I got chasing other cars. You know how it is. The best was a new 370Z which was a bit of a chase - great fun.
Janel also spent some time in the driver's seat, of course. She started off a bit tentative, but got faster and faster as the day went on. On her last session, she pointed by a couple of cars and then proceeded to reel them right back in again. It really got her competitive juices going and all three drivers had a fantastic time.
The car felt good, but not perfect. The right front shock felt low on fluid again, so I'd get some shaking through the wheel on hard right turns when it was unloaded. It didn't affect grip at all and it worked fine when the wheel was heavily loaded on lefts, so I just dealt with it. Otherwise, the car rotated nicely with a good high speed balance, and the new diff worked well to pull the car out of corners very strongly. The tires were working well, even though I have a pair on the front that I used to set the car up for the Targa more than two years ago! They're pretty well worn as you might imagine. A few other drivers commented on how quick the car was for a naturally aspirated Miata! Part of that was the car's ability to hold speed through the corners, it really reeled in other cars on the fast corners. Both Janel and I found it comfortable to really smear around the track at high speed, forgiving but agile. Like a Miata is supposed to be.
The car spent between three and four hours on track today, and was as reliable as an anvil. We just kept pounding around and around and around the track, with Janel and I doing back-to-back sessions so the car would usually run for a full hour at a time without a real break. A really fun day.
Video will come later, as will some reports on Targa 2010.
entry 763 - tags: track, testing, HPR | | |  | September 13, 2010 - New video!
I've put up a clear lap of the High Plains Raceway. I have a few more with me chasing down various cars, and I may put them up later. Janel's the one who got in the best scraps anyhow!
Video
There were some truly delicious cars at the track day. The green 260Z in the foreground looked great. The 635CSi hiding behind it is one of my favorite car designs, but I have yet to convince Janel of its inherent goodness.
entry 764 - tags: video, high plains raceway | | | September 14, 2010 - More video!
Again at High Plains Raceway, but this time there are other cars to play with. I'm still learning the track and not running as fast as the other video at the same track, but it's fun to see where the Targa car gains on the high power turbo car.
Video
entry 765 - tags: video, HPR, GTR, turbo | | | September 23, 2010 - I spent last weekend at Hallett, near Tulsa Oklahoma.
I was there with one of the Flyin' Miata shop cars at a Miata event. So no Targa car and not even any AFCO suspension. It's a pity, because that track is relatively rough and would have been a fun test. Still, it was a good weekend. The car I was driving was a 2006 model which made for a very interesting comparison to the 1999 we had also brought along. The newer car has a very stiff structure and generated surprising levels of grip while coping with the rough surface. In fact, the more hard-core 1999 wasn't dramatically faster.
The 2010 edition of the Targa finished while I was there. I might not have run in the race this year, but I did spend three days on tracks I'd never seen before and racked up nearly 3000 miles of driving going to and from various tracks! So it was about as good a substitute as I could have arranged.
The 2010 event was quite eventful. Lots of lead changes in Modern with a number of cars encountering problems. As with last year, I kept up a running commentary on the race on the Grassroots Motorsports forum. Yup, living vicariously.
entry 766 - tags: hallett, 2010 | | | October 5, 2010 - Over the past couple of years, I've had a number of questions about the Backsaver foam that we used in the Corbeau seats.
It made all the difference in the world to comfort, but it's not cheap stuff. Well, a recent phone call from a customer made me dig up some of my old information, and I'm pretty sure it's actually Confor CF45 foam, 1" thick with an extra piece of fabric on one side and a rubber pad on the other. Armed with this knowledge, you can find less expensive sources elsewhere as long as you're willing to forgo the rubber and fabric. It's hard to believe, but aviation stores such as this one are actually a less expensive source.
If you're looking for a way to make a set of race seats more comfortable, this is a great place to start.
entry 767 - tags: ergonomics, comfort, seats | | | October 11, 2010 - The local Corvette club had an autocross yesterday.
I haven't run through the cones for a while, but it was just a few minutes from my house so I figured I'd go out and have some fun. Brandon brought out his bike-engined Seven so I had someone to play with.
The car is set up exactly the same way it was at High Plains Raceway. Heck, it hadn't even been out of the trailer yet. I did put a bit more pressure in the tires, as the cooler weather had dropped them down a few pounds. I also wanted higher pressure for the short autocross runs instead of 20-30 minute track sessions.
The car felt pretty good. The first run was a scrabble for traction, but this particular lot is always slippery at first due to a lot of dust. I softened up the shocks a bit (two clicks in front, one in the rear) to help it grip the rough surface and because it felt a bit too stiff to me anyhow, and that helped. The car would grip well at the front up to a certain point, but I still spent a fair bit of time trying to manage my front grip. A large part of that could have been my driving, as I suspect I was sawing away at the wheel too quickly and breaking traction. It's an easy bad habit to get into.
More interesting was the fact that I seemed to have too much front brake bias. Now, the lot was fairly slippery so that means less weight transfer and thus less (relative) front traction - but even with the rear brakes turned up all the way I couldn't get the back to rotate properly. I found the same thing the last time I was at our local track. I did recently replace the front pads, and I suspect the front brakes are simply working too well. I'll try swapping in some new rear pads and see if that solves things.
While I wasn't completely happy with my driving, the results were pretty good. Brandon walked away with the event because nothing can touch a Seven in the autocross, and we left before the final runs of the fastest drivers. But at that point, I was around 2.5 seconds ahead of the next car, giving me a solid second place. Can't complain there!
entry 768 - tags: autox, brakes | | |  | November 14, 2010 - The new Miata book is here!
I got the call from my editor suggesting this title when I was driving through Nova Scotia on the way home from the Targa, and it's finally a reality. "How to build a High Performance Mazda Miata" is a technical book that explains the theory behind how cars work, what that means for the car and how to make it work to your advantage. Turbocharger and supercharger theory and design, the role of weight transfer in handling, even safety and aerodynamics.
Naturally, the Targa Miata makes quite a few appearances including an inset photo on the cover. It's used as an example several times of how to make design and setup choices to achieve a certain goal.
I'm proud of this one.
entry 769 - tags: book | | |
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