What have you done to your Miata today?

We’ll be down south mid Jan thru mid April, it would be great to come see the amaff mobile in person!
 
actually, a few days back, but worth post SPAL fans are the best! just installed them and they work awesome....great cooling!
 
Installed Paco Motorsports alignment cam locks in the rear to stop them slipping around, and added a bit of of camber on 3 out of 4 corners (see also: cams slipping). Well, the fronts were where I left them last time, but I want to try a little more camber, and 1 of the rears had definitely moved.



The Paco locks are a bit of a pain to work with and adjust, but the idea is that it'll have 0 toe all the time, and camber can be independently adjusted with the upper control arm, so the locks won't need to get adjusted hardly ever. The instructions weren't super clear on the process for adjusting them, but after a bit of trial and error, I figured out a process that worked for me.

The setup pads might be the best things I've ever built, they make doing this job SO much easier & more consistent.
 
Cliff's notes: Saturday: YAY! Sunday: YAY! ... BOO ... YAY! ...but still boo


Had an emotional roller coaster of a weekend (rlaugh)

Saturday was our final points event of the season. I'd already wrapped up our local XP championship, so it was all for fun, but I ended up taking home another Fastest Time of Day. I was in the hunt against some stiff competition in the form of a pair of C7 Corvettes in pretty cold temps (I really only got 1 hot-tire run) but I managed it. It's the first time in my autocrossing 'career' that I've ever come off course to a round of applause :D

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The electric power steering continues to be fantastic. Being able to make small, precise corrections via fine control muscles, rather than having to put chest & shoulder into each input has made a big difference.



Sunday was our Champion of Champions event, which is run like a 2-day National event. 3 runs in the morning, 3 runs in the afternoon on a different course, and your time is the combined best time from each session.
The morning went well and had me 4th in our Club group (ie: a group made up entirely of people who'd won their class for the season). The afternoon...less well. After my co-driver's 2nd run, it did not want to crank for my 2nd run. We push started it and I made my 2nd run without much issue. I came back in and we pop the hood, expecting to find the alternator belt gone (because the battery clearly wasn't getting a charge). The belt was there, so something else was up. We started checking wiring and found wires at the back of the master cutoff switch with their boots melted, and the insulation discolored. So, day over. I was able to stand on that 2nd run, however, and move up a spot into 3rd, somehow.

The car's run flawlessly for 3 years without letting me down, so I'm not too put out with it :)


I haven't properly torn into anything yet, but my theory regarding the failure is that: I ran the last 4 years with an underpowered lawnmower / ATV battery that, any time it was REMOTELY cold, made the car a cast iron b*tch to start. I switched to a LiFePo this year, that weighed 1/3 as much but had 3x the CCA. Starting this year has never been a problem. It was pretty chilly in the mornings this weekend (low 40s), and it was REALLY hard to start each day. Like, harder than it's ever been. Sunday we had to hook jumpers to the tow vehicle to get it going. My suspicion is that the prior years of prolonged time running the starter with an underpowered battery damaged the wires, and it managed to limp along ok until this weekend it finally fell on its face. I'm probably going to have to replace all of the wiring to the charging system.

Either that or the alternator crapped the bed and has only been marginal during the weekend, and finally shorted completely out on Sunday, overloading the wiring and making everything toasty. I'll likely do some tear down and testing today.
 
I would put $1 on a loose or poor electrical connection at the joint that melted. A spot resistance there would hurt cranking and cause localized heating/melting. It could be as simple as a loose lug or bad crimp, or as sneaky as a slightly-bad master switch contact. It is a failure mode I've diagnosed on other master-cutoff enabled cars before, one time the lug nut was loose and the starting current had welded the nut in a 'backed off' position!

Whatever it is I'm sure that you'll sort it out. Congrats on a good end to a great season!
 
Failure analysis: the Master Cutoff Switch finally fudged the bucket. The alternator isn't shorted (still going to get it properly tested), and there's continuity from the alternator to the terminal on the master switch, but there is no continuity across to the other pole on the master switch (yes, with it "ON". I tested both switch positions).
I'm led to believe that Master Switches are a wear item on race cars, and do eventually go bad.
And if it was flaky for a couple events, it probably had a ton of extra resistance on the way out, building up heat and melting those boots on the terminals & heating the wires like James said.
 
Thanks!

Current mood:




Oh, I got a kick out of this yesterday during the lunch break, when the 2 Prepared class cars were, without any collaboration, both parked under our tech shed and had their hoods up for various routine checks. Not pictured was the Street class Vette that came in and was up on jacks a few minutes later to change his shock settings, while all the Prep / Mod guys were sitting around giving him s*** and telling him all the things he was or wasn't doing wrong (rlaugh)

 
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So, back home (finally). I made a few small purchases before I came home. A set of 949 valve stem seals (since I don't know what was used in the P&P head I bought) along with a couple of tools to make the job easier. Today when I bought my wife her daily Starbucks tea I also picked up a straw. This will become clear once I start the job and post some pictures. What, you didn't think I would post pictures?
 
Miata: Finally got started on the cylinder head. Here are the main tools I used:

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Here are the seals:

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949 uses the same exact seal for both intake and exhaust valves. I removed the keepers, retainers and springs on the intake side first, here is what that looked like:

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Compress the spring with the first tool until the keepers are clear of the groove they fit in, then remove them (I used a small magnet to grab them). I used the same magnet to pull out the retainer and spring. I then grabbed the seal with the removal tool, rocking it slightly side to side until the seal popped out. It was good I did this as the very first seal was completely torn. Not sure when this happened but I would have had a massive leak for sure.

After cleaning everything up I proceeded to install the new seals. First I used some engine oil to lubricate the seals so they would go into place with no damage. Then I unwrapped the straw and put it to use, here is how:

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Had to fold it a little to get it started in the seal. You then push the straw down over the valve stem and use a 10mm socket to seat the seal, like so:

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This keeps the groove at the top of the valve stem from tearing the seal. I was able to push the seals in place with my thumbs, but I did take the precaution of tapping on the socket with a dead-blow hammer. A couple of them weren't quite all the way home so it was good I did this step. All that has to be done then is to put the spring, retainer and keepers back into place. There should be a thin metal washer below the spring, this is the lower spring seat (it gives protection for the aluminum of the head from the spring). I found one missing so ordered a complete set. One thing to note, the springs go into the head with the coils that are the tightest down (you will know when you see this). I found four of mine installed wrong. I tried putting the keepers in by hand but it's very difficult. Instead I used a little trick I read about which is to use some plastic (I used a storage bag). You place the plastic over the top of the retainer once the keepers are in place. Then use the spring compressor and compress the spring until the keepers fall into the groove on the stem. Works great. For now I have everything assembled except for the one valve that was missing the lower seat. Once I get the parts in I will redo all of them as several looked as though someone had taken a Dremel to them and hogged them out. Maybe that is how they are, but I seriously doubt it.

Apologies for the picture quality, all of our good cameras had no battery so I was forced to use my phone.

I also managed to locate my old shift and e-brake boots so put those back on, along with the console lid that had leather on it.
 
Machined and installed steering rack limiting stops on the depowered-but-not-really steering rack, installed the rack in the car and roughed in the alignment. No more tire-to-swaybar interference with the 10" wheels :D







 
Since I first made ballast for the racecar, I have gone to bigger wheels and tires, added all the aero bits, added power steering (and the heavier PS rack), and a few Hill Climb safety bits and bobs. As of this morning, the car was about 59 lbs overweight.

Started at 1983 lbs (minimum is 1924). I got down to 1932 (ie: 8 lbs over), with about 1/2 gallon of fuel in the car. I wouldn't really be comfortable with that tight of a margin, but I never run it that low, fuel wise, so there's a bit more wiggle room than it would seem.

I was able to drop 1 of the two 5/8" thick lead plates, and cut about 1/4 off the other one.

 
Got back from our Christmas trip. Went to the dealer to pick up the lower valve spring seats I bought but one was missing. They ordered me another overnight (that is what I call service) and I picked them up yesterday. Today I had a little time in between granddaughters being born so went ahead, brought the head back inside and commenced work.

Here is one of the seats:

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They are the same for both intake and exhaust, so you will need 16. Here is one of the old ones next to the new factory ones (new one is on the left):

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As you can see they are completely different, and the one I removed has been hacked up. All of them were like this. Since the factory one does not have the markings I have to wonder where the ones I removed came from.

Here is a picture of a valve spring, the tight coils are shown on the bottom which is installed down nearest the valve:

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I followed same procedure I documented before. I did try something a little different on a couple of the valves where I placed the keepers inside the retainer before setting it in place on the valve stem. This worked ok, although I had to be a little more careful when putting the valve compressor in place.

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Finally, here is how I used the plastic to hold the keepers in place while compressing the spring:

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I would recommend using clear plastic so you can see when you have the spring compressed enough for the keepers to fall into place. And that is all there is to the job. Easy-peasy.
 
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Got back from our Christmas trip. Went to the dealer to pick up the lower valve spring seats I bought but one was missing. They ordered me another overnight (that is what I call service) and I picked them up yesterday. Today I had a little time in between granddaughters being born so went ahead, brought the head back inside and commenced work.

Here is one of the seats:

39350424192_8dcac25744_c.jpg


They are the same for both intake and exhaust, so you will need 16. Here is one of the old ones next to the new factory ones (new one is on the left):

39350418412_47fa004dae_c.jpg


As you can see they are completely different, and the one I removed has been hacked up. All of them were like this. Since the factory one does not have the markings I have to wonder where the ones I removed came from.

Here is a picture of a valve spring, the tight coils are shown on the bottom which is installed down nearest the valve:

39350423222_671ca28d78_c.jpg


I followed same procedure I documented before. I did try something a little different on a couple of the valves where I placed the keepers inside the retainer before setting it in place on the valve stem. This worked ok, although I had to be a little more careful when putting the valve compressor in place.

27603170729_4e5aa0ed56_c.jpg


Finally, here is how I used the plastic to hold the keepers in place while compressing the spring:

24514993097_eebd72206b_c.jpg


I would recommend using clear plastic so you can see when you have the spring compressed enough for the keepers to fall into place. And that is all there is to the job. Easy-peasy.

Good stuff!
 
Hey guys. I don't have a miata but I did see this badboy today roaming around northeast philly. LS swapped and sounds amazing.
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It's been too freakin' cold here for me to want to get out in the garage, also there is something (cold or flu) going around the house and it's been kicking my ass. I did get up to the dealer the other day and ordered a new plug for the cylinder head where the CAS is on other models. Figured while I was getting everything else new on the head I might as well take care of that to prevent any surprises. I also picked up a soft top insulation piece off eBay, it says it won't work on a factory top but I am banking on my ability to do so.
 
One of my codrivers came over and we spent the day re-dialing in the setup on the car after the diet & new steering rack. We re-did the corner balance, improving the front/rear balance while maintaining 50/50 cross weight. We then re-did the alignment after the ride height changes (from the balancing) and the new steering rack. My brother and I roughed the front end in last week after we installed the rack, but I knew it needed the rest of the work too before it could really be finalized. Should be good to go now.

I have a few odds and ends I need to wrap up (clean the wiring up again, etc) but all the big work is done and she's ready for the season to start next month.
 
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