Long story short. I bought a nonrunning 1993 SC400 got it running. Then traded for a fairly rough 1993 Miata.
The miata runs and drives and leaks oil. It has coilovers and a welded diff. Header and “custom” exhaust.
List of projects that now have parts ordered:
1. Speedometer cable I don’t know if I can drive it again until this is fixed, the sound is awful.
2. Stop oil leak, going to try CAS oring and valve cover gaskets but it seems like it is leaking a lot so I don’t know if it will be that simple.
when the car is just parked will this continue to weep oil?
Other projects
3. There is no O2 sensor so that is on the list of things to look into as well, or should I get a wideband sensor just for fun?
4. Alignment car just looks out of spec to my extremely untrained eye.
Chassis swap donor? Perhaps fix it and drive? What's your plan?
In reply to Indy-Guy :
I would really like to do a chassis swap to my corolla wagon, as it needs basically everything but the body is ok for a 80’s Toyota. But I know that is way beyond my skill level.
So for now getting it to stop leaking oil and then drive it is the goal.
I am also intrigued by the $2000 challenge. But that is a very far drive from Ohio and I don’t have a lot of mechanical skills, and I have only auto crossed once or twice and that was about 10 years ago.
I think I have about $550-$600 in the Miata trade deal including the parts I bought for the SC400. So I have some room for the challenge if I really wanted to do it.
In reply to Somebeach :
1. Speedometer cable is not too hard to replace, you don't have to pull the whole gauge cluster, just the cover. There's a video on YouTube that shows it pretty well even if the guy is a little odd. *LINK* Be careful when removing the cable from the transmission, either have the replacement ready or just pull the cable, not the whole plug. Otherwise you'll make a mess of gear oil and need to top off the trans. (Though it would probably not hurt to get new fluid anyway...)
2. Oil Leak, makes sense to start from the top down. Once you replace those gaskets clean the engine as best as you can and then drive it and see where else it might be leaking from.
3. O2 sensor. Are you talking about the front O2 sensor that is usually at the base of the header near where it connects to the rest of the exhaust? If so I'd just replace with stock. should be about $50 IIRC. On the 93 I'm not sure if there is one farther back, but I think it's just the front one. Unless you're planning to turbo I would not bother with a wideband O2 sensor.
4. Alignment, hard to say from pics. If you're handy you can do it yourself, but personally it's usually worth the $80-100 to have someone do it with a proper machine.
Also, I have a rear finish panel in good condition in Waynesboro, PA if/when you feel like messing with that. I could make you a decent deal.
A gen in the rough some would say, but I say with a bit of maintenance it should be able to be a fun reliable car!
Also, unless you are planning on drifting, you'll want to replace the diff with one that's not welded. It's probably and open diff to start, so putting another open diff in would likely be easiest, but Torsen swap is also an option.
Hey another Ohio Miata! If you are on Facebook definitely join the Ohio Miata Owners group. There is a ton of great people in the group who would be willing to help you out with any of the mechanical bits and finding parts. I would offer to help out on the potential challenge effort, but I out of the country on a work assignment for the foreseeable future.
In reply to AWSX1686 :
Thanks for that link that was really a nice step by step on the speedometer cable.
I will keep you in mind when I get to the finish panel, seems from reading on it they are rather fragile. I am going to take it step by step with the looks down on the list as of now.
I think there is supposed to just be one O2 sensor. I think the aftermarket header and exhaust they just left it off all the way. I only have the female connector and that is all in the engine bay for the sensor. Not even a cut off male pigtail or anything.
In reply to AWSX1686 :
Yeah was an open diff to start. Seems like I will be learning a lot on this car. How bad does a welded diff hurt on autocross? Does it try to push through a turn? I am sure it wears out tires fast.
In reply to rodknock :
Yeah just joined that Ohio Miata group. Thanks
Somebeach said:
In reply to AWSX1686 :
Yeah was an open diff to start. Seems like I will be learning a lot on this car. How bad does a welded diff hurt on autocross? Does it try to push through a turn? I am sure it wears out tires fast.
I've never actually driven a welded diff car, but my understanding is street driving will be impacted with wheel hop around turns (or broken parts depending on what gives). Autocross I would venture to say would be similar, but possibly more likely to break stuff. Welding the diff is to make sure both wheels are always spinning, and forces them to always be the same speed. This makes it good for drifting where you want lots of tires spinning, but for a normal turn, wheels need to be able to move different speeds.
Hope that makes sense. There's definitely more info online if you look into it. I know some people do drift welded diffs on the street, but it does put more strain on the driveline.
In reply to AWSX1686 :
That does make sense thanks. I guess I may learn how to swap a diff on this car as well.
In other news got my speedometer cable in. Sounds much better as in no sound at all. The link that was posted above was really helpful .
Next up is stop the oil leak
Thanks to EvanB I got a oring for the CAS. Also got an OEM valve cover gasket.
Started working on it it this morning, just gave up for now, it is 26 degrees out.
I got everything taken apart. Got the new oring on the CAS. I can see that the dogs are lined up bc the valve cover is off. But the CAS just feels like it hits a brick wall and won’t go back in.
I also tried it 180 the other way Incase I spun it as I was getting it out. Won’t go in either ways.
Any tips?
After some further searching. Tried grease on the o-ring and “hole” that the CAS slides into.
Did that and pushed it harder than I thought I should and it popped back in.
List is now:
Speedometer cable- Done
CAS O Ring - done
Valve cover gasket-Done
O2 sensor-next
Went out tonight, when I was replacing the oring and valve cover gasket the pcv valve broke and so did that hose and the hose on the other side of the valve cover.
I replaced both hoses and a new pcv valve.
Start it up and it sounds really bad, started right up but has a loud ticking noise.
https://youtu.be/I-bDUDRG7fw
Any suggestions on where to start figuring it out, had no loud tick before, also have never run it when it was this cold before either if that is relevant?
when heading inside I noticed there was some soot and quite a bit of condensation on the ground out of the tail pipe 
Soot and condensation is normal enough in really cold weather. Ticking is probably sticky valve lifter (HLA in Miata speak) and is exacerbated by the cold.
In reply to TurnerX19 :
Thanks, that gives me a place to start.
Plot twist with the rusty Miata, after reading one of John Welsh posts about buying a salvage car it got me searching on IAAI.com.
In my search came across a 1990 Miata at the location in Columbus. I asked John some newbie questions, and he was a wealth of information. Thanks for all the help John.
I ended up gambling a little bit because I couldn’t go and inspect the car before bidding. I set my high pre bid price, and settled in for the excitement.
I ended up the high bidder. So I now am the owner of two red (semi junky) Miatas. The salvage auction one came with some surprises.
From the looks of it once had a multipoint rollbar that the back shelf was cut out for. ......and now has just a “regular “ roll bar ie not one that attaches in the trunk area any more
also peeking through the wheels shows some drilled and slotted rotors
And some sport seats
And the damages
and throw in a little rocker rot
The Miata number two started right up and drove off the trailer into my building just in time for the snow to start and the below zero temperatures to start.
The plan is now, thanks again to Johns guidance on how the process works is to move the bumper, taillight over from Miata number 1 onto Miata number 2.
Get a airbag for the steering wheel. Get the horn to work and then schedule an inspection to get a rebuilt title.
Well played!
Is the second one Challengebound?
In reply to Indy-Guy :
I think I will try to do an autocross or two locally this summer, and see how that goes and then see if I could make the schedule work to try the challenge.
I have only done 2 autocross days and that was almost 10 years ago now, so will try to dip my toe in first.
Got some work done last couple of days.
Took all the broken stuff off the salvage Miata and also the corresponding usable parts off the rusty Miata.
Of course the rusty Miata gave me some fits. Two rounded nuts and then two studs that just spun. 
The drivers side all four came out ok. It was of course the passengers side so I had less room to work with the muffler in the way.
That was the last guy I had to get out. It took forever to cut it off. Crappy harbor freight blades, I think I could have used a butter knife just as fast .
Anyways once I got that stud cut off it came off pretty easy.
The bumper cover has a couple of cracks so I drilled the end of the cracks (I think I saw that somewhere on here to stop the crack from getting worse) and then did the zip tie stich to keep it together for now. 
Last up for the night was to replace the studs to mount the bumper to the car that I had cut off. Luckily I still had the mounting brackets from the salvage car so I drilled out the rivet, and searched for a bit and bolt to hook it back onto the bumper.
I tacked the nut to the bracket and went to put it into the bumper and at this point realized the top and bottom are spaced out differently.
So I drilled out the rivet in the correct narrower width and then just ended up using a self taping screw in place of the rivet
Did get much work on the salvage Miata done tonight but I did a lot of looking at it.
Looks like it also has a Borla exhaust.
I took a picture of the label on the spring does this tell me anything ie lowering spring or spring rate etc?
The next thing on the list is to try to push out what got pushed in the the wreck.
I think I got lucky that the hit was higher up in the trunk area rather than in the bottom where the subframe rails are, those are straight as can be.
I used a 2x4 to point out where it starts to bend in.
Here it is straight when compared to the non-wrecked parts car.
Then at this height it starts to pull in just a little mostly on the left side
By here is the majority of the problem area when comparing to the good parts car it should be about a 2-2.5” ledge? From where the bumper is to where the finish panel sits
here is what I have
then under the key hole on the right it is about the correct 2.25”
My plan was to use a bottle jack and a couple of boards to push it out, the question is do I use heat and how much?
I have a heat gun a little propane torch and a oxy torch ( which I have never used, it works but it was a garage sale find)
Starting to work on this again. Moving the bumper from the parts car over the the salvage car. I can’t remember if these holes in the bumper cover bolt to the hard plastic thing that comes out of the fender or not ? 
There are holes in the bumper cover and bolts in the black thing, but they don’t seem to line up.
I was able to use a rigged up bottle jack to push out the sheet metal above the bumper that was pushed in.
Here was my set up.
got the parts car trunk on.
I also now have the parts car bumper on. But it is not sitting flush all the way around. So That will go on the list once I get it inspected, for now I just want to do the least possible to get the rebuilt salvage title and then go from there.
Next up is to make some seat brackets so I fit into the car, get the taillights back in, and then get the horn to work and I should be good to go.
Rear end buttoned up except for a finish panel.
On to the horn. Looks like someone cut the wire that should have the connector on it really close to the steering wheel.
So I am going to see if I can find the other end of the connector somewhere under the steering wheel. And then hope I can splice a connector back on that super short wire somehow.
