Compression tests said "rings!" so the shop pulled the head aaaaand yup, rings. On it's way out one of the rings dug a furrow deep enough in the cylinder wall that honing isn't going to be enough. The shop owner (Jeff) and I both were like, "Hey, it's a 1.6 liter Miata block. No one wants those things. Let's just pick up another block on the cheap and keep going."
Yeah, right.
Jeff's junkyard sources found three in the nation. All expensive. I dug through the usual suspects (Facebook Marketplace, Craigslist, and a post on this forum) and found a remarkable lack of 1.6 blocks. 1.8s? All day long. Kinda handy for my future engine swap, but not exactly what I was looking for at the moment. All I can think of is maybe the Spec Miata crew has driven up demand like they did for the hardtops? I saw that happen with Formula Ford and also Porsche 944s - the racing classes got so popular that the supply of cheap parts from old cars eventually got used up.
Could I accelerate the transition to a 1.8? Yes, but I would rather not rush the build and install, and I really did want to attend a few more track days before Phoenix temperatures get so bad that we all hide inside until November. I'd be perfectly happy running with the 1.6 for the next year or more while I get used to the car and get everything else sorted to my satisfaction.
Options as I see it:
(I'm adding a catch can to the currently vented side regardless. It's a smart thing to do imho.)
(Sean put in decent-enough rods already per his build thread.)
1) The Bare Minimum: Slap some rings on it, hone the cylinders, bolt the thing together, keep an eye on the oil level, maybe drop the boost a bit, and hope nothing else gives out on this fine 160,000 mile engine before I'm ready to do the engine swap.
2) Fix it: Drop a repair sleeve in the damaged cylinder, then do rings/hone/lower boost levels
3) Solidify It: Bore it, new pistons, high tension rings, go through the head and do new valve springs and seals (and possibly stainless valves), and replace the harmonic balancer while we're at it. Keep/Increase Boost.
I could always throw a little head work at options 1 or 2 as well, of course.

I know options 1 and 2 wouldn't require messing with the tune - not sure how much option 3 would. A conservative bore on a 1.6 really wouldn't change the volume more than a few percentage points and with the head basically the same, just with newer/tougher bits...? I dunno. I've got a lot to learn in the tuning department.

I do have a nice hood to put on the car when the engine is fixed though. >.>

 

Nice work on the vents! Looks super functional and tidy.

For the motor, I'd hold out and keep looking for a 1.6. I bet you'll find one. Make sure to look for old capri's as well, they shared the same motor. **** I have a buddy with 3 of them in his garage here, they aint that rare. I have one too, but I'm saving it for my GTX or I'd offer it up.

It would be a shame to build or put too much money into the 1.6 when your goals are 1.8 and you've already started accumulating parts. Maybe just speed that transition up?

 

IMO, if you're looking to get back out on track just hone the thing and slap it back together for the time being. If you already have plans to build a 1.8 later I don't see much point in sleeving this engine or building it. Have any photos of the bit you're talking about? Really, this option seems to depend on how long quickly you want to get back out there, how long you want to drive on this engine and what you want to do with the engine when you pull it. If you're trying to sell it and it's in questionable shape you're going to be in a weird situation IMO. It really depends on how deep that gouge is I suppose.
*I built one engine, so take that with a grain of salt. Someone with more experience might think that's a terrible idea.

Entertaining other options, grab a 1.8 now and throw that in. Then when you build the other 1.8 you'd have this one as a backup, plus if the 1.8 is reasonably healthy you wouldn't even need to open it up for the time being. Also, if you don't want to hold onto a backup engine, this would be easier to sell than a questionable 1.6.

 

Nice work on the vents, and cleaning up the bonnet. But that angle is fugly. I would remove it on public decency grounds, and see how the cooling performed without that leading edge shield. Keep it in the spares box, it isn't cooling as expected you have the option to immediately re-install it.

Those vents will make a big difference to removing under-bonnet air, but as mentioned above they are dependent on that air, all-of-it, having gone through (not around) the radiator - the two are complementary (additive even), not alternatives. In a hot climate you are going to need everything going for you.

 

Just throwing it out there. Just sleeving a cylinder or even the whole block is not very expensive.

 

I've got my eventually-to-be-repainted leprous original hood for looking pretty if I need it - the ugly-but-very-functional gurney flaps are staying. I'm in good company with that - the first version of the singular hood vents had separate gurney flaps too. Just not as stupidly large.

Early Singlular Yarn Test

I hear you on cleaning up airflow through the radiator - That's now at the top of the punchlist along with the splitter and installing my nifty new Sadfab front brake vents. Now I just need my car back so I can get going on that.

Sadfab brake vent prototypes!

*Sigh* Yeah, I'm leaning heavily towards spending the money to make sure the 1.6 holds up reliably for the next year or two. Like SimBa pointed out, I'll have much better luck selling it (if I choose to) if I fix it properly and it's not like it would be cheaper to wait to repair it. Plus I want the car to work. I don't mind doing the aero stuff and minor break/fix stuff but my favorite part of all this is driving the car at speed. For that, I need (or would at least prefer) a working, relatively reliable car. The engine I've got is a known quantity - with some decent parts and a refresh I figure I've got about as good a chance as any of keeping it on the track.

Speaking of keeping it on the track, while I've got the valve cover off, should I remove the three baffle plates? With a catch can on both sides moving forward is there really a reason to keep them?

A Baffling Question

 

That tuft test is pretty convincing I have to agree, I haven't seen that before.

Sean is going to get an email about those ducts ...

On the VC baffling, not sure what the centre cover function is, but the other two keep flung oil away from the PVC and breather outlets, I'd say definitely keep them - if you have ever run the engine after forgetting to put the oil cap on you will know there is a lot of oil flung around in there, and the vapours exiting the VC will carry a lot of liquid oil with it. Better option is to do the tiny hole mod to further reduce the flow of liquid into the catchcan(s).

 

Yes, keep the baffles but open up the passages with drill bits. The larger openings will allow the air flow to slow down a little bit. Adding some sort of media to the interior of those chambers will also encourage the oil vapor too be collected and drained back. Just don't use anything that might melt or shed particles.

 

Ah, darnit, I'm sorry you guys had to repeat stuff that was already posted. I read the wrong tiny hole mod thread and couldn't figure out what the best practice is. Thank you both!

I went ahead and drilled out the 1/4" hole to 5/16", cleaned everything off and then put the baffle covers back on using black oil-resistant RTV and blue oil-resistant thread locker for the screws. I opted not to use any additional filter media because:
1) Until I lost a ring I really didn't have much landing in the catch can as it was so it doesn't seem like additional media was needed
2) I wasn't happy with any of the options for media anyway - has to be able to handle high temperatures, can't lose bits that could end up in the engine, not supposed to be a different metal than what's already in there because of bimetallic corrosion or something (even though the baffle plates are steel and the valve cover is aluminum?), etc, etc.
3) Increased the potential for poor airflow if it gets plugged up and/or I do it wrong
4) It means more work If I have to pull the media out for whatever reason. I'd rather not. There's too much else to do to the car as it is.

5/16 Passage

Cleaned up the larger passage with a little dremel work. Until the stone broke. >.>

Then I repainted the valve cover.

Basic Black. It doesn't show dirt.

Ok, the lettering can show dirt if it wants.

 

So. There she sits. At the shop. While I wait for the head and block to go to the machine shop for a teardown and recommendation on what should be replaced. *Sigh*

Parked at the shop

Now would be a Great Time to get at stuff...if I had anything I knew I needed to get to! >.<

Missing something

The shop guys (including the owner) are having a blast working on the car. Since it's a "normal" shop they hardly ever get a chance to wrench on anything customized at all - most of their work is just break/fix so my little Miata is apparently rekindling their love for hot-rodding cars.

Headshot!

You know you're not looking at a lot of power output when the lead mechanic looks at the pistons and comments on how little and cute they are...

Blockshot!

Another Blockshot!

I dropped off the intake and exhaust manifolds at a local performance coating place this morning to have them ceramic coated since they're already off of the car. I was willing to at least consider doing my super-high-dollar (NOT) turbo done too, but they said I'd have to tear it down completely and that's not happening any time soon.

Hard to do bodywork when the car isn't here.

Hard to work on the splitter/radiator enclosure/brake vents when I don't have the car around for measurements.

Maybe I'll start practicing the fiberglass-ish work I want to do. *Sigh*

 

In that particular engine bay shot, I'd scrub the bay and subframe, and brake clean the bell housing, inside and out. Great time to change the throw out bearing/clutch if it's not to your liking or the TOB makes noise, same with pilot bearing.

I'd personally be going 1.8, but that's another story.

 

Thank you for the Excellent Suggestions Curly! They shop is checking the clutch/flywheel/etc since we're in there, but so far all of that looks ok. Good thing too, since between work and everything else going on I haven't had time to do more than drop off parts. :\ This weekend won't be any better - I'm working flags at the track again. I'll try to grab a few interesting pictures if I can.
If I had a 1.8 I trusted then yes, now would be a great time to do the swap. I don't though, so I'm just going to beef up the 1.6 some, pull together the parts for a nice 1.8, and do the swap when I'm ready. I've been doing a ton of reading on this forum so I can make better educated choices for both the current 1.6 and the future 1.8 engines. So much to learn! The repairs are progressing slowly; no huge changes, just beefing things up. Hopefully I'll be back on the road in a few weeks.

 

I'm OK with the 1.6, sure the 1.8 is better in every perceivable way, but the 1.6 is a fun and tough little motor. I never blew mine up and learned to tune on it. And by tune I mean copy/pasting maps from this forum and autotuning it. It took a lot of abuse and made 245whp on a terrible turbo setup. I actually still have that motor and it's gonna go in my backup 323gtx, eventually, maybe, or at least that was the plan before it got backlogged on the list of projects. lol.

Good work on the valve cover mods, looks good to me. Makes me want to go clean mine up with the carbide bit now that I have better tools.. If you use a substrate to collect oil vapor the thicker pure copper (not coated) scrubs were the winner, IIRC, any steel wool is gonna rust and break up and get into places it shouldn't and any nylon plastic kinda **** will melt and cause more harm than good. I didn't add anything to mine, just opening up the passages and adding larger bung(s) for the catch can was plenty. If you do add a substrate make sure to add it to the first baffle not the 2nd. The first (center) baffle drains down into the 2nd, so if you catch oil in the 2nd one it can never drain back to the head - so you don't want oil condensing there.

I feel like I know way too much about VC breathing at this point because I read every thread I could find on the subject twice when doing mine. My mild-built motor needed it and has been perfect ever since.

 

The various 1.6 engine bits have been back and forth between the shop and the machine shop a few times and are currently being combined into a (hopefully) reasonably solidly refreshed engine. The last track event before the summer is in 2 1/2 weeks. I have no idea if I'll have a car by then, but it'll be a decent car by the time it's done! Plenty of "while we're in there" stuff as well, like an entirely new clutch kit including the relevant bearings. (Good suggestion there Curly! Thank you!) Other than running parts over to the shop as they come in I've got nothing progressing but time. *Sigh*

Last weekend was flagwork at Firebird International Raceway - I worked corner 7.
Turns out that unlike virtually every other track I've worked, Firebird has no shade structures over any of their corners. Like, zero. I didn't bring my awning for the first day, so I spent all of Saturday hiding under a loaner umbrella and getting sunburned despite using insane amounts of sunscreen.

A View from Umbrella Corporation

One somewhat unusual feature of the organization I race and volunteer with is they don't use red flags. At all. They have shirts and equipment using a red theme instead as evidenced by the umbrella I was peeking out under for the day.
The next day I brought my popup and things were Much Better. I set up a camera on a tripod (and a gopro on the cement barrier) and grabbed a few stills while watching for incidents.

Super Modified
This super modified is absolutely insane. It's faster than anything else on the track and has been setting track records ever since the owner got it dialed in. A few months ago I was working a corner at the end of a long straight and here came this car. I watched something fly out of the car, sail up into the air about 20 feet, and then skid along the track and out into the dirt. Later in the day when the track was cold I went to go see what it was, and discovered a very battered cellphone the driver had been using as a lap timer. He was happy to get it back. It still worked, too, which says a lot about the case it was in!

'Stang
Some other interesting cars go romping around the track too. But hey, this is a Miata forum, right?

Miata ******* a Cayman

Miatas!

Race start, Miatas included

There were many more Miatas, actually, but these were the more interesting pictures that included them.

Oh, and here's a little clip of why I'm out there in the first place.

 

Fire, you have given the best summary of the substrate discussion I've seen in any thread. Heck, I read through the two main discussion threads until I got a headache and I never picked up on which baffle areas to put the substrate in! This is absolutely brilliant.

 

A little progress - got the manifolds back from my local performance coating shop (less than 6 miles away! Woot!) with a fresh Ceramic Coating. Everybody keep talking about how their fromitz board or oscillation overthruster keeps melting from under-hood-temps so I'm now worried enough to spend money on magic black (or is it black magic?) paint to help keep the bad heats away. Shoo bad heats, Shoo!

(And I like black because it doesn't show dirt as much. Or blood. >.>

Back-er. Black-er.

I see the Miata every week or so when I'm dropping off parts. There it sits, getting dirtier and more dilapidated looking each visit. :( Things'll get better little guy. Just give it some time.

Poor little car...

 

Still waiting for the engine on the Miata, so here are some pictures from more engine bits I painted a few weeks ago.
I had some leftover super-duper-heat-resistant header paint, so I went ahead and threw a coat on the turbo. Maybe it will help keep the Bad Heats in or something, I dunno. I had the paint, it was there, bada-bing. Painted turbo.

Masked and doused in cleaner
I pulled off the easily-removed stuff (after labeling everything and taking a lot of pictures), drowned the turbo in brake cleaner until it was at least marginally less filthy, masked the snot out of it, and then gave it a good spray with paint-prep cleaner.

Painted
My paint booth (the back yard) has been seeing a lot of use recently! No windstorm today so it ended up being a pretty clean paint job. In Boring Black. Because Black.


Pieces going back on
I figured I'd better err on the side of caution when painting the thing so I masked off anything that might not like getting painted (and several bits that probably don't give a rat's.) Here it is, as painted as it's going to get, with various bits ready to put back on. Those with keen powers of observation will note I have a few different sets of sawhorses in various colors of overspray. Those same folks would see the vented hood and one of the repainted decklids in the background, waiting for the Miata to come home just like I am.


Pile of parts at the shop waiting to be put on.
I have a few different piles of parts at the shop. Here's the pile with the turbo, manifolds, the braided clutch cable I got from sixshooter, etc. Not everything in the pile is for the miata. I Truly Hope Jeff (the shop owner) can keep track of all this.


Still moldering at the shop
The caption pretty much says it all.

Since I'm not-so-quietly going more-crazy without a car to putter around with, I figured I might as well knock out some side projects - here's an example of one.

Now that I'm doing really, really bad bodywork stuff I've acquired a fair assortment of spray cans. I also occasionally make other things that require painting (paper cutting frames, for example) so I finally got fed up with all of the spray cans piling up everywhere and decided to do something about it. The pretty paint can organizers on amazon are expensive and the reviews say they're junky, so I decided to make my own.
Wood is Stupid Expensive, so I opted for the absolute cheapest stuff I could find at home depot. Cedar Fence Pickets at $3.28 a pop.

Cedar Pickets
I bought six pickets, used two for the sides and cut up the other four in 2' sections for shelves. Sanded everything down and screwed it all together. Did I take pictures of any of that? Nah.
Since the shelf is intended to hold paint and other various chemicals it seemed like painting it would be a Very Good Idea - that way if something leaked it wouldn't soak into the wood and cause a potential fire hazard. Instead it would hopefully pool on the ground and cause a potential fire hazard there. With this well-thought-out plan in mind, I broke out the cans of black rustoleum paint that Amazon accidentally shipped when I asked for white paint. They also beat the snot out of that shipment so the lids and sprayers were damaged and some of the cans had been partially emptied. At least they didn't charge me for that case of paint! Anyway here's a picture of the unit after I painted it. Please note that I wasn't going for a pretty finish on this unit - if that had been a goal then I wouldn't have made it out of fence pickets. >.>

Painted

I then waited for the paint to dry. And Waited. And WAITED. Four days for the paint to dry! At least it's consistent - that's how long it took the rustoleum to dry when I was painting the body parts too.
Following that same "let's keep the chemicals flowing to the floor" line of thought, once the paint finally dried I drowned the whole thing in polyurethane.

Polyurethaned

I went ahead and sprung for a $13 piece of plastic coated backer board at home depot too. Since I don't have a panel saw I had them do the cuts. Got home and found out the kid had cut the board 1" short. Apparently I'll have a nice gap at the bottom to, um, prevent chemical pooling. Yeah, it's a design feature. >.< Even though it was plastic coated I threw a coat of polyurethane on it anyway because why not.

Backer Board

And here's the final product, screwed to the garage wall and all loaded up with lovely chemicals to hopefully not mingle and cause terrible fires. I might actually be able to find what I'm looking for now too!

Done!

 

Work on the Miata is still on hold as we wait for the engine to come back from the machine shop. I kinda feel bad for the guys at the shop - every morning they push the miata out to their lot, and every night they push it back in to the shop so they can lock it up. I try to drop by once a week to visit the Miata, take a picture or two, and chat with the owner - Jeff has some crazy stories to share!

May 24th

Sometimes it's an abbreviated version of "Where's Waldo" as I look to see where they've tucked the Miata today...

May 31st

It's usually here in the southeast corner of their lot, though. The hood was popped today because...

June 14th
...they've started cleaning up the engine bay in preparation for the upcoming summer blockbuster, "Return of the Engine" which is supposed to show up Monday. Unless it doesn't.

Getting Cleaned Up!

Honestly with no A/C and temperatures above 110' and climbing it's not like I'll be using the car much for the next few months anyway. NACA duct vent windows! That's what I need...

 

Visited the Miata this weekend - it's still at the shop. Got a few new layers of dirt.


Moar Dirts

However...the engine is back. In plastic wrap. The car goes up on the lift in the next few days and Jeff says it'll be done in the next week. Considering the mountain of loose parts they've got to contend with, I think they've got their work cut out for them. O_o

It's Baaack...

Here's the refreshed head - it looks really good! Hopefully I won't get this view again for a loooong time though.

Refreshed Head

In other news I've been looking at the 9lives wing I won in their scratch and dent auction and trying to figure out the best way to mount it on my car. I ended up getting one of the smaller wings because the bigger ones were being bid up to painfully high prices. That's how I ended up with a 48" one. I was poking around on the 9lives website to see what methods they use. Huh, funny...their street **** for NA Miatas is 48"! I called them today and they Very Kindly agreed to send me a set of endplate pylons for a price I can live with. They're even including the hardware! This is Fantastic News for me because I had always planned to get a full-size wing when the budget permits and reportedly all of their wing mounts use the same hole patten to mount the pylons. I won't have to drill new holes when I upgrade. I'm Really Happy with the folks at 9Lives for being so helpful, and Really Glad I bought a wing from them! Now I just need to cut off the mounts on the 18" mark on the wing. Or just leave them. I dunno. >.> In any case I've got my next project lined up once I get the car back.

 

I was over at the shop yesterday dropping off my other money-pit car and grabbed a few pictures while I was there. The engine reassembly continues.

Engine - Front


Engine - Side


Engine - Other Side!


The Workspace

The chassis was up on the lift so I was able to grab a few shots of the underside including a view of the exhaust system with the two resonators added - they really quieted things down, at least outside the car, and since they're straight-throughs they shouldn't adversely impact airflow. However it's still so loud inside the car that it's hard to have a conversation - One of my punchlist items is to pack the pass-throughs from the trunk to the cabin on each side of the gas tank with mineral wool insulation - shouldn't add much weight, it's fireproof, and it reportedly can really help. If I don't feel like it did much then I can always pull it out again, but I would like to be able to have a conversation with passengers when I have them. Huh, is that the driver's side boss frog frame rail there too? Sean added all sorts of cool chassis reinforcement to this car, bless his heart.

Resonators

I also took a look at the front end to try to figure out how I'm going to mount a splitter. There...isn't much room there. I'm reasonably certain I can't just staple it to the wheels either. >.> Guess future me gets to figure that one out.

Driver Side

Passenger Side