Targa Miata
MIATA BUILD
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 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
September 15, 2011 - Time for Garnish.
This is a fast, fast stage with a very rough road. It starts off with crests (or "cresty" as it says in the routebooks, which I find to be a very amusing word), gets bumpy, then takes a detour into the small fishing town of Garnish where it becomes extremely rough, then back on to bumpy for another fast section to the end. We were catching air in fourth gear over the crests and really testing the limits of the suspension both on compression and droop. What a fantastic little car. We did punish the skid plates somewhat as you can imagine, and the rear finally buckled under pressure and bent enough to contact the exhaust. No real problem other than a big of vibration - and more importantly, no damage to anything important. If the plate hadn't been there, it would have been our exhaust and diff. We came in 29 seconds late, partly due to our lack of GPS and partly due to my self-preservation instinct on the hammered pavement. 200 km/h is pretty fast when the car's being thrown around like that.
Garnish was followed by a very short lunch, as we had to get back on schedule after the marine Enzo shenanigans. Two runs through Fortune, which is a tight town stage that's like a mini Gander. It works well for us, and we came through with 2 seconds of penalties the first time. The second time, I was faster but we had a tighter time and I think we picked up four. But that doesn't matter, because there was another accident that shut the stage down and that meant no scores for anyone.
So we headed back out to the Garnish course for a run in the other direction, named Frenchmans Cove. Long, fast, bumpy. Going through the town, I ended up using first gear and the handbrake to get around some of the corners and it worked very well. We were still suffering from a lack of GPS on the long cresty bits, which both of our main competitors in Open were using. Still, we were only 4 seconds behind the fastest car in the division and holding on to our lead. It was an exhausting run through the stage, both due to the physical battering and the mental stamina to drive that fast on that pavement for so long. There's no Miata in the world that could have done it faster.
entry 985 - tags: 2011 race, day 4, Garnish, Frenchmans Cove, Fortune, skid plates
September 30, 2011 - Back home and up on the lift, it's time to check out how the car fared.
Well, score one for skid protection. My UHMW sliders got a good workout protecting my catalytic converters, which is exactly what they were built to do. I think that small skidmark on the cat was already there. The front skid plate didn't take too many impacts, but there were a couple. One of them might have done damage to the v-band connecting the header to the exhaust system had the plate not been there.
Other teams - notably the army mechanics who were working on the Soldier On car - were quite impressed with the undercar protection. It worked.
entry 1005 - tags: protection, skid plates
September 30, 2011 - Overall, the car is in excellent shape.
The rear subframe brace took the worst beating, which wasn't a surprise. Ground clearance back there is at a bit of a premium and my experience in 2008 was that the back was the most likely place to hit. The skid plate/brace did exactly what it was supposed to do and protected the important bits.
Elsewhere, there's very little sign that the car just finished such an ordeal. In fact, all we need to do is bang the rear skid plate into shape and we could run another week. Even the tires would be good for a few more days of racing. We replaced a coil that had heatsoak problems due to my heat shielding, had a video camera die (and lost a GoPro off the roof at speed) and of course lost the main relay. But overall, the car proved itself to be a strong and reliable tool with a huge turn of speed. By contrast, I was speaking to one of the MINI drivers after the event and he had a big list of problems to fix. For example, both of his front upper strut mounts were damaged and he'd replaced them once or twice already during the race. We had no similar concerns.
I've also been thinking about The Relay. At the time it happened, I felt that I should have been able to fix it on the side of the road and rejoin the race without the DNF for one stage. However, it wouldn't have made any difference in the end. By the time we'd extricated ourselves from the car, set up the triangles and OK sign, instantly diagnosed the problem, reloaded ourselves and rejoined the stage, we would have lost too much time to catch the Challenger and the M3 that finished ahead of us.
entry 1006 - tags: impact protection, skid plate, post-race