| MIATA BUILD |
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 | |  | August 3, 2011 - Nancy in full livery.
Most of the sponsor stickers are on the back half of the car, where we can get more contrast and visibility with the solid black rear instead of trying to fit in the mixed white and purple. We will have to load the car up with an undisclosed number of event stickers as well, so we're leaving room. The one sticker on the front half of the car is the Heifer International logo. They're not a sponsor of the car, but Flyin' Miata is a sponsor of theirs.
Check out the new black C3M wheels wrapped in new Dunlop Star Spec tires in a 245/45-17. Thanks to Tire Rack for donating the wheels and Dunlop for supplying tires. Why a 245 when we've been running a 255 in the past? Because Grassroots Motorsports found that size to be measurably quicker in their testing on a car very much like ours.
Both cars will spend the next two days pounding around the track, showing off their abilities to Flyin' Miata fans. It'll also serve as a good shakedown for them. Neither car is completely in Targa spec yet, but they're close.
entry 900 - tags: Nancy, tires, wheels, sponsors | | |  | 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 | | |  | August 10, 2011 - Gratuitous track shot.
This angle reminds me of another. But dustier.
Photo by Benjamin Padolsky
entry 902 - tags: testing | | |  | August 10, 2011 - Time for some work on the car.
I put it up on the lift yesterday and came up with a good to-do list. One of those items was to deal with the slipping alignment cams. The red powdercoat on the new arms - and on the subframe as well - was part of the problem, so I took it off. I also used a file to roughen the back of the washers on the cams and tried to avoid getting any lubricant on them. Between that and some good strong torque, things should be good in the future. But we'll mark the cam locations once the car has been through final setup before the race.
I also swapped in my 400 lb rear springs. I'm looking forward to how it will feel.
entry 903 - tags: alignment, suspension | | |  | August 10, 2011 - One of the biggest concerns with the car is ground clearance.
I'm running a higher ride height and stiffer springs than before (the race setup last time was 375/300, this year is 550/400) which will help, but the V8 exhaust system does hang down more than the four-cylinder setup did. One of my solutions is to delete the resonators. It's a bit of a shame as I really don't want to make this car any louder inside, but they're the lowest point of the car and this gives me a significant improvement in clearance. As you can see, I've already damaged one!
The catalytic converters have a similar problem, but they're required by the regulations. The good thing is that they're a metallic core, so they won't shatter on impact like a typical ceramic setup. Still, I'm doing what I can to tuck them up a bit and protect them.
Between front and rear suspension work as well as this exhaust modification, there were bits and pieces all over the shop today!
entry 904 - tags: exhaust, ground clearance | | |  | August 10, 2011 - One of the ways I'll be dealing with the rough roads was picked up from the Stillen team in 2009.
I'm using UHMW (ultra high molecular weight) plastic pieces as sliders. If the car does ground out, it'll take the brunt of the hit instead of abrading metal. Here, I've put a piece in the middle of a stock cross brace that I'll later weld to the rear subframe bracing. It'll not only protect the exhaust and differential, but will stiffen the rear control arm mounting points. Everybody wins!
entry 905 - tags: UHMW, skid plates, undercar protection | | |  | August 13, 2011 - I finally have everything I need for the in-car video system.
It's taken a long time to get to this point! In 2008, I had an old Canon camera that recorded on to DV tapes. It took pretty good video when it was working. But I did lose the video from a few stages as it started to inexorably zoom in and eventually lose focus. The other problem was the soundtrack - it was ambient noise only, and you simply couldn't hear Janel unless it was a relatively slow stage.
This year, I've got the new intercom with an audio out. That'll feed in to one channel on the camera. An in-car microphone will feed in to the other side, so we'll have the choice of playing the ambient noise, Janel's instructions or both blended together. This means a collection of adapters. I managed to find the only Radio Shack employee left in the world who knows his way around the stacks of bits and pieces in the back instead of just trying to sell me a cellphone, and he provided the last couple of parts I needed to adapt the microphone output to my various patch cables.
The camera itself is a Kodak Zi8. It's a "Flip style" camera, with the added bonus of being able to record to SD cards. I can also power it off the car's power, so this means we never run out of recording time due to space or battery. Excellent. It's got an audio input, which is pretty unusual in this type of camera. And I've even seen in-car video footage from a rally car, proving that it gives a good picture and does everything it's supposed to. Woohoo! The real test will come in a couple of weeks when I return to the track for the last time, but so far so good.
entry 906 - tags: video | | |  | August 14, 2011 - I have lots of important work to do on the car, but I'm back to painting wheels again.
It would have been a lot easier if I'd just stuck with an off-the-shelf color, but the car looks much better with white. Besides, it's easier to inspect the wheels for damage this way!
So, after trying rattlecan paint from the auto parts store and powdercoating, I'm back to doing things right. That means real automotive paint and clearcoat. First, I had to clean the set of rattlebombed wheels of all the brake dust, rubber and debris from several track days. Simple Green, scotchbrite pads and a session in the bead blaster followed by a wipe-down with wax remover and they're ready to shoot.
I spent 45 minutes building this wheel rack out of a half-dozen 2x4s. It might seem like overkill, but it means I have the wheels at eye level so they'll be much easier to paint. Plus I can do both sides at the same time and, since they're supported by the barrel I don't have to worry about the paint on the rims getting damaged. Well worth the $12 investment in materials. I'll do this set of wheels first, then follow up with the second set later.
Tomorrow I'll be back to work on the car itself!
entry 907 - tags: wheels, paint | | |  | August 14, 2011 - Emilio from 949Racing is very concerned about sub-standard wheels getting out.
Because my powdercoated wheels were weakened, he asked me to render them unusable so there's no chance they'd end up on a car. I respect that. He suggested a 1/2" hole drilled in the barrel as well as a nice dent on the rim so nobody would be tempted to put them back in service, along with ensuring they went straight to the metal recycler. I had a different plan.
Just how strong are a set of good wheels? I've seen reviews of aftermarket wheels in a German magazine that included destructive testing, so I figured I'd take the opportunity for a bit of non-instrumented destructive testing myself. Besides, it's a lot more fun to use a sledgehammer than a drill. It's much harder to wreak this level of destruction on a set of 6ULs than you'd expect, even those with a heat treating problem. They're tough. We were all surprised at how hard we had to hit the lip in order to dent it, and knocking the center out requires quite a bit of determination. Emilio, it's fair to say these aren't going to get rescued.
For those who want more details on the actual problem: as part of the T6 heat-treating process, these wheels are aged at 350F for about 18 hours. Powdercoating takes the wheels up to 400F for 30 minutes, which can "over-age" the alloy and make it more brittle. I've heard - first-hand - of a German NC owner that had the stock wheels powdercoated and they cracked on him.
There actually is a 15x8 on the market that comes in white: the new Konig Wide Open. The weight is about the same as the 949Racing 6UL as well. I chose the 6UL over the Konig because of a proven track record - the 6UL is a well-known wheel that should take the abuse of the Targa, and Emilio stands behind his products. It's meant a lot of extra work on my part to make them white, but I think it's worth it.
entry 908 - tags: wheels | | |  | August 15, 2011 - Now that's how you're supposed to finish wheels.
Four coats of 1990-93 Miata white - which is actually almost pure white paint - finished with three coats of clearcoat. A nice smooth, hard finish that looks good and should shrug off brake dust. The special rack worked perfectly, making it easy for me to lay down a good coat without having to gyrate around. With the wheels at eye level, I could easily see how well the coverage was going down. Excellent.
entry 909 - tags: wheels | | |  | August 17, 2011 - Time for some impact protection.
The car has a few vulnerable areas such as the now-removed resonators. The metallic cats are also a potential problem spot, and they are required. I've actually grounded them out already doing some testing to discover exactly this sort of problem. So I welded a piece of 1x2" tube to the bottom of the frame rails and bolted a 1/2" piece of UHMW plastic to that. This means the slippery plastic will hit the ground just before the cats do, and avoid any damage. I also made a couple of extra skids just in case.
Yes, it will be a potential problem if the road is uneven. But that's something I'll have to keep in mind. Just like driving off-road, high spots should be run under the wheels instead of straddled.
After the picture was taken, it was all painted flat black.
entry 910 - tags: skid plates | | |  | August 17, 2011 - I also want to protect the oil pan.
It's welded aluminum instead of cast, so it's more likely to dent than to crack if I hit it. Still, there's no benefit to beating up the pan so I've put together this critter.
Made of 3/16" (I think) aluminum, it was an opportunity to practice my aluminum welding. I don't do this very often, but it usually comes back pretty quickly.
entry 911 - tags: skid plates | | |  | August 17, 2011 - The oil pan skid plate in place.
It's quite easy to install, just hook the curved section over the front of the subframe and bolt it to the car using the two rear mounting points. Everything is protected but it's quickly removed for service. There are a couple of things I could do to make it stronger and I may do that if I get the chance, but at the moment it should protect things in case I make a mistake and bottom out the pan. You can see the side skids are just about level with the back of the plate.
entry 912 - tags: skid plates | | |  | August 18, 2011 - Brandon surveys his new race car.
In case you missed the announcement on the FM site, Bill broke his shoulder over the weekend and is unable to race. Brandon, trying to act sympathetic but secretly giggling like a little girl, has stepped into his place. Now he's working to get the 2006 ready for the race. The plan to run a set of Corbeau FX1 Pro seats has been set aside - Bill doesn't find the stock NC seats comfortable, but they fit Brandon just fine. He's also working on smaller things such as wiring in the Terratrip rally computer and generally sorting out where everything will go. Reading the rulebook over and over is a big part of preparation for the event, to make sure there are no surprises at scrutineering.
entry 913 - tags: nancy, brandon, accident | | |  | August 18, 2011 - Not all the work on the Targa car is big cool projects like skid plates.
It's also getting some maintenance. For one, I'm changing out the front hubs to make sure they're at full strength. The current hubs had a total of about 10,000 miles on them but a large proportion of that was with hot race rubber bolted on. And, just like the original build, I had to grind off 75% of the teeth on the ABS trigger wheel in order to drop the number of pulses per mile to a reasonable number. The ABS sensor is used to trigger my Coralba rally computer, and it can only deal with 16,000 pulses per mile or so. With the modified ABS wheels, I get about 9,900.
And then I found a problem. The replacement hubs have an ABS ring that's about 2 mm smaller in diameter than the stock part. This meant the air gap to the non-adjustable pickup was too big, and it wasn't triggering the rally computer. That's not good. Luckily, the rings are just pressed on so I pulled off the old stock one and put it on the new hub. If only I'd noticed that before I spent all that time grinding!
entry 914 - tags: hubs, wiring, computer | | |  | August 19, 2011 - Lots of little jobs on the car today.
Mostly exciting things like wiring in a permanent power supply for the intercom and installing a wideband air/fuel gauge in the car. Plus some nut-and-bolt checks and other glamorous jobs like an oil change. But I did take a few minutes to put this little guy together.
entry 915 - tags: maintenance | | |  | August 19, 2011 - Here's what that little doodad does.
It's a brace for the brake master cylinder, tied into the shock tower brace. This should give a nice solid pedal - not something that's ever concerned me with this car, but it can't hurt. The brace is ridiculously simple, just a steel tube with a nut welded to the end. A threaded...I'm not sure what to call this thing, it's basically a bolt with a knurled knob at the end...presses up against the end of the master.
Did I have better things to do? Maybe.
entry 916 - tags: brakes | | |  | August 20, 2011 - Race rubber!
The painted 6UL wheels are an awesome, blinding white. Whiter than the powdercoat was, which is kinda nice. They've now been mounted with the actual tires that will be used in the race, a set of six Toyo R1Rs in 225/45-15.
A rehash of the tire rules that led to this choice: I am allowed a maximum of six tires for the race, and they have to have a minimum of 140 treadwear. This means I can't run a tire such as the Toyo RA1 that did so well for me last time. So the Toyo R1R is it.
entry 917 - tags: tires, wheels | | |  | August 20, 2011 - Off the lift and on the road.
It's time to get the engine tuned properly and make sure the suspension setup is good. Basically, everything needs to get the final shakedown.
The alignment will be sorted out in a few days. One nice feature of the V8Roadsters control arms is that I can play with camber to my heart's content without messing up the rear toe or the front caster. I'm still fine-tuning the damping settings for the 550/400 spring rates, but that should go fairly quickly.
The big thing is the engine. I've decided to take a different tack with how to set it up, and things are progressing fairly quickly. I'm just setting up air/fuel ratios without using a MAF at the moment, and it's possible I might just run that way during the race. We'll see how well the MAF dials in. Once it's all set up, the long-term fuel trim will make sure it stays that way.
As part of the fuel tuning, I'm working through the entire repertoire of the engine: low rpm, high rpm, low load, high load, etc. And at higher rpm, when I nail the throttle this car just boogies. It's still a bit rich down low so that will get stronger as I keep working.
entry 918 - tags: tuning, alignment, suspension, testing | | |  | August 22, 2011 - A bit of extra airflow management thanks to Mark Rivera at Paco Motorsports.
The NACA duct and the turn signal intake helped, but the air pressure underhood is just too high for them to really make a big difference. So these louvered panels will pull hot high pressure air out and make room for the cold stuff. As an added bonus, they'll keep the hood from lifting above 100 mph.
There are some larger ones available on the market, but I wanted a small set for a few reasons: they fit better around the underhood bracing and they'll fit with the Martini livery! Yes, perhaps that last reason is a bit shallow. But I don't care. The panels were punched out by Mark to my dimensions - thanks Mark!
entry 919 - tags: aerodynamics | | |
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