Two 1990 Miatas - STS Autocross, CSP Hillclimb, PR Rallycross

Remedied the crappy half-assed diff install last night. Then I couldn't sleep and noticed Pagoda was about 10 entries from full. So I signed up. Have until June 18 to punt and get a refund if I can't get the car together. Ordered harness and fire ext today. Priced out/checked availability of all personal safety stuff so that is only 3 days/$500 away when the time comes.

Required by 6/18 to make a go of this:

• Bar install
• Seat install
• Harness install
• O2 sensor
• Intake/filter mount
• Upper rad hose + bleed cooling system
• Bleed brakes
• battery (stole it for the sts car)

Optional but very much preferred:

• Front calipers, pads, hoses.
• Actually install the good suspension rather than running a floppy ES car in CSP.
• drive it ? Huge regional autocross w/ really really nice test and tune setup on Friday but I won't have the rusty car ready for that I don't think. TNIA next Tuesday. Maybe. Then I can't make any other events until the actual hillclimb. Dunno how I feel about that.

Progress and un-progress.

O2 sensor in.

Battery in.

Intake/filter in.

Mirror...off. Crap.

Now we are getting somewhere. Top out, carpet out, seat in position, mirror most of the way fixed, 3 pounds of dirt, rust and cheerios vacuumed up.

Well, Pagoda is a no-go. End result of doing a lot of cutting and roll-bar-curls on Friday to get the bar in by myself is that even sitting on the floor I do not have 2" of room above the helmet to the bar. Need to do more research on bashing things with sledgehammers and layback aluminum seats and that kind of stuff. That's not gonna happen in a week for $0 which is what I have to work with at the moment. Taller roll bar is not an option because I need to be able to put a hardtop on the car. But hey, I fixed the passenger window so it rolls down now. Yay?

On the other hand autocross this weekend went great and I am sadly reminded that hillclimb does not have this depth nor strength of competition in class, doesn't have PAX for when your class is weak, doesn't have ridealongs with friends, and I know like 3 people in that crowd as opposed to 50. Enthusiasm has waned a bit for now.

Cursed water plug blew in the STS car on the way home from Pocono. Really glad it didn't blow on course because some shiny happy person already oiled down the track on Friday and caused a large cleanup bill for the SCCA region. You'd think I'd have bought an extra plug and kept it in the car after losing the same plug on the rusty car a few months ago. Nope. I am not that smart. AAA to the rescue, and in a very timely manner to boot.

If the same freeze plug blows out multiple times, I'd put a cheap OEM block heater in it. The bolt should hold it in, drape the cord off to the side AND then you'd have a block heater if you ever ice race that thing.

They're not freeze plugs in this case (idunno why everyone calls it a plug) but an unused water passage from when the engine was designed for transverse FWD applications is covered with a dinky rubber cap. Oil from the leaking CAS seal above it drips right on the rubber and a few years later you get this result.

https://www.youtube.com/embed/xKEYhR-vxUg

Video from the STS car that spent the weekend mostly in one piece. Somewhere along the line my brother got pretty quick. We traded the lead back and forth 4 times during our fast runs and he had the raw time to beat me by 0.06 but grabbed one cone along the way.

CSP car still a temporary shelf. Looking more seriously at my budget constraints, I think it may just get daily driven for the rest of 2016.

STS car was fixed in 3 minutes. Topped off the coolant and burped it a little and off we go. We had quite the local STS class at the autocross this weekend with 9 entrants. There was myself and my usual competition in a CRX who has been getting faster and faster. Then the previous (fast) owner of that car was codriving it with him on a whim. I had a codriver, a friend who is pretty quick but drives a poorly-classed MazdaSpeed3. Finally another friend who is usually on par with all of us but took some time off, brought his freshly assembled '94 r-package Miata out for its first event. So, 5 friends and then 4 other guys for a class of 9. The CRX was on nearly new tires, my car was on (2) 160-run tires in the rear and (2) 80-run tires up front. The 1.8 Miata was on my other 'dead' set of tires which ranged from 1.5-2/32" of tread to completely bald.

During our heat we were 1-3 in PAX and 4th/5th place STS guys had the raw times to be 4th and 5th in PAX as well but coned it away. Sweeping the top 5 pax places for our heat would have been cool but didn't happen. By the end of the day the top of our class was 1, 2, 5, 10 in PAX out of 140.

Everybody went home happy. 1st place was the CRX's codriver, he was glad to win the whole event since his own car is currently all blown up. 2nd was the CRX owner, thrilled that he beat me after getting clobbered at Pocono last event. 3rd was me, I was happy to be that close to #1 and finally in the top 5 PAX again, it's been a rough start this season. 4th was my codriver the mazda3 guy, for whom it was the first event in a Miata and he was having the time of his berkeleying life. Seriously. After one tentative run he got the hang of the car and put down (3) very consistent times to end up 4th in the class and 10th overall on his first time autocrossing a RWD car. I think he may actually have struck a deal to buy a Miata already, just 3 days later. And 5th was the guy with the new build, he had the raw times to compete despite the trashed tires, and it was the first event for the car in this trim and his first event for the season. Good news all around.

Some Photos...

The winning CRX:

Me scaring a novice:

Suspension looks like it's working OK:

One of my dead tires got really-dead:

And this is how (5th place car):

But dayum do they stick right down to the last bit. I can't actually blame my non-win on tires a single bit, they still get plenty sticky. They're now at 170 runs on one pair and 17x on the other set of 4 and if I wasn't concerned about highway rain safety I would keep running these til I find cord. It's gotta be in there somewhere right?

Then I got on the highway to go home and realized...crap! Rear shocks were set too high all day. Yeah, the car was a little loose, I blamed it on the tire mismatch and dropped rear pressure a little. That made it better but still not planted like it has been this year. Well, turns out rear rebound was a full turn higher than I intended and I completely forgot to adjust it.

When you can open the rear window, 4 tires in a Miata is not that bad.

Found a really cool product from a friend for removing bug/tar/cone marks. In particular cone marks. Washing/scrubbing with normal brushes/sponges/fingers/'bug sponges' wouldn't touch this:

I don't have any actual detailing skills, I HATE it. But this little scrubby thing worked wonders:

This is the thing:

https://www.amazon.com/Safe-Scrub-Bug-Tar-Pad/dp/B0002LAC6E/ref=sr_1_4?ie=UTF8&qid=1467293821&sr=8-4

Also available other places, I found it cheaper at autogeek actually. For someone with no desire to do anything but wash the car and maybe wax it once a year, that was money VERY well spent. Got all the bugs off the front of the daily drivers with minimal effort too. It does need to be soaked like the instructions say, but I found that soapy water was too much lubrication and it stopped working after a few good scrubs on each side. Switched to straight water and it was back to working miracles.

Now I need to do a wax-stripping wash, I guess, because there's cone marks I waxed over this winter and therefore won't come off now. Yeah, that was smart.

So two years ago I was feeling spendy and bought fancy new Magnacore plug wires and everyone's favorite NGK plugs. And promptly installed them on the garage shelf and that was that.

After being away for a week and a half of vacation, I fired up the Miata to drive to work and it was running on 3 cylinders sporadically. OK, in a Miata step one is plug wires. But oddly it cleared up at high RPM and when plug wires fail they usually get worse with more RPM in my experience.

Whatever, let's dig in. Pulled the first wire and hey, that's a whole lot of oil. Same for #2. #3...was actually submerged. I'm gonna assume this is the non firing cylinder. #4 also wet. Valve cover gasket time! I have an OEM one lying around because why the hell not, I am great at buying parts 'in case they are needed while i am in there, it's only another $20' and then not using them. This is not economical nor grassroots but it comes in handy at times like now. With no plans to work on the car at all, I had all the parts on hand to fix the problem in an hour.

All four plug wells had oil, #3 was absolutely swimming in burnt black stuff. Don't delay maintenance this long! I hadn't touched any of this stuff since 2013/18k miles. And it was on there when I got the car. At least the plugs looked OK and still had the right gap. #4 maybe slightly leaner/hotter than the rest?

And this is why. VC Gasket so brittle it came out in pieces. I've done a bunch of these and never saw one that bad.

All back together with fancy wires. Because red is faster than blue, of course.

The butt dyno says it has more low end grunt. That could be BS but it is definitely smoother and easier to drive at low speed low throttle actions like moving away from a stop or shifting in traffic. Shoulda done plugs/wires ages ago :(

Hopefully STS is again ready for an autocross this weekend. After 2 weeks out of the car I wanted a little practice before Wilmington. Headed down to a BMC event (I believe run by Duke on here?) in Newark on Saturday. Leisurely 9am arrival time, and a two hour tour of amish country twisty roads to get there, and hopefully 6 runs. And less than 80 people signed up. Should be a good time.

Autocross was indeed a good time. Brutally hot, but a really well designed course that was a blast to drive. Some clubs that run at tiny lots try to cram 70 second courses into them and it is painful. None of that here. Quick, flowing 28-30 second course, 80 some cars got 7 runs each, and off site by 3:15pm. Great day. 9 cars in STS. 8 were Miatas, plus that grey CRX mentioned above. I beat him this time.

Aa friend lives 2.5 miles away with a pool so after swimming for a bit and waiting out the passing hailstorm that dropped temperatures by about 20 degrees, I enjoyed a gorgeous summer evening drive home with the top down. (route 896 and route 10, from DE all the way up to Reading PA)

This club usually has some cool cars in attendance.

And this one was driven like an absolute madman on his first two runs, after which he calmed down and ran some respectable times:

I still want one of these. Someday when my fabrication skills allow me to weld one up.

There was also an 80's El Camino with a Corvette drivetrain, an LS1-swapped 240 on Hoosiers, and other cool stuff you don't often see autocrossing.

The course. It was very well suited to a Miata and I was gunning for FTD but Wally showed up with his STU 350z and put a stop to that. I got him in PAX though, by a whopping 0.006! The new shocks, when set properly, make this car a friggin' dream to drive. It turns in instantly with no push, it rotates beautifully with early throttle, and yet I can chuck it through a slalom and trust the back end to stay planted. I don't even know how that combination is possible but I love it. Video from that Z, it doesn't capture the sound but trust me that thing is amazing to hear run. Looking at his video he could have been closer to a couple of cones, and on my fastest runs I overdrove the stretch entering the finish, so we both had time to gain. Ah well. Still good for 1st in Raw for him and 1st in PAX for me.

https://www.youtube.com/embed/VcFaLBg_RN8

Like I said, fun course. Short and to the point.

STS car blew the diff (#1). After 400+ clutch drop launches over the past 2.5 years, it developed an awful road and card-in-the-spokes noise. Pulled the diff, took it apart, there is obvious binding between the ring and pinion and absolutely no backlash. After cleaning the drain plug earlier, I drove 15 miles and generated a bunch more shards. It's done. This was used, unknown condition, and $60 along with axles and a driveshaft. It did its duty.

To the naked eye, I see nothing wrong. Do teeth look OK?

Ok, so I'll throw the spare in (#2). The super low mile "known good" spare. Ah...no...it has a massive input shaft seal leak and a bit of a hum (but no pulsing/rhythmic noise at least). This was $450 in a package deal with a set of 15x7.5 wheels. So I guess it was more or less free. But not overly useful as a quick solution. To replace that seal I need to rebuild the whole thing AFAIK. berkeley.

I have one more "spare" (#3) located under the rusty car, that was obtained by straight trade for the open diff that was in that car previously. It is known to have been abused, and though the previous owner swears it works fine I have not actually driven on it yet. But hey, this one was also essentially free.

So I suppose I am not out any money yet but I am tired of swapping diffs. ATP 205 ReSeal went in (#2) diff last night and I have been driving the car to get some time + heat on it but I don't expect it to do much. Just marking my territory with every stop:

Time to pull rusty out of the garage and see if that diff is quiet and well-sealed. If it is, I will shove it into the STS car for now. Also possibly picking up a new "spare" later this week. Over winter I will do some rebuilding with the guidance of a friend who has shimmed a few diffs, and should end up with 1-3 nice solid units. But that's not gonna happen anytime soon and I would like the car reliably on the road for the rest of the season.

At least with rubber diff bushings and the stock exhaust back on (so I can hear the rear end at speed), the car is relatively smooth and quiet for a bit. It's nice.

My 12mm socket had been stuck on one of the differential mount secondary nuts for 2.5 years and 18,000 miles. Back in the toolbox now, apparently none the worse for the wear.

I just pulled the 1.6L VLSD out of my car and did the Torsen swap. When I was picking up my Torsen from Expoline he asked me if I raced and when I told him I did, and launched at 4000rpm on Dunlop ZIIs, he just stared me in the yese and sai "You play with fire". Well, then.

When on concrete with RE71...5200rpm.

Hey, so, um, what you doin' with that VLSD? Wanna sell it?

RedGT wrote: When on concrete with RE71...5200rpm. Hey, so, um, what you doin' with that VLSD? Wanna sell it?

5200RPM?!

As for selling it, I might be... persuaded. Although my father saw it sitting on the ground and went "Hmm, go-kart?"

I live in constant fear of blowing up my diff.

I know they are weak but what exactly is the failure point on the 1.6L differential? I'm guessing with the 6.5" ring gear and lower gears having a smaller swept area, they get a case of tooth decay.

50/50 whether it's the pinion or ring gear that goes first, but the outcome is the same

Yep. In my case it appears to not be catastrophic failure, but a bearing failure on the input shaft allowing the thing to bind up/wildly vary the mesh and backlash between ring and pinion. You can turn it by hand and it gets tight and crunchy at random points but with no consistency in where on the ring or pinion. Maybe it could be saved but I am no expert.

NickD wrote: As for selling it, I might be... persuaded.

Let me know if you do. I like trying out other regions for autocross, 3.5 hours each way for 5 minutes of racing and a diff wouldn't be the stupidest thing I have done.

In reply to RedGT:

How did you do at Wilmington?

In reply to Spoolpigeon:

Borrowed car was super loose. Calmed it down some but couldn't get my driving together. Ran a trophy worthy time on the right but never drove the whole left course well on the same run. Couldn't trust the car so i was either having a slide or way-too-slow entry speed to every element. Finished 11 of 19.

I think i have a solution to get my own car to the big concrete events next year. Very motivated now.

Don't beat yourself up too bad over it. Finishing mid pack in STS with mistakes is pretty good. That class is fierce!

It's weird that you had trouble on the left side. Left was rock solid for me and I struggled with grip on the right.

In reply to Spoolpigeon:

I just "saw" the right side better. I usually get one pro course right and butcher the other entirely. My lack of confidence on the left probably led to all the spins, slides and underdriving there. Which is why i say, although i hated how the car was turning i can't really blame it. Gotta do something to get a handle on both courses.

How did you do/what were you driving?

In reply to RedGT:

I was codriving the yellow MR-2 spyder in ES and won the class. It was a good weekend!