1993 Mazda Miata -1.8 Swap/ Flyin' Miata Turbo Kit

Next I began work on painting the valve cover. I like red valve covers on black cars. A friend who convinced me to use wrinkle paint and make it look like a Ferrari valve cover.

I thought about powder coat as I have a small setup in the garage but was concerned about oil in the baffles leaking out during the baking process and making a mess. I have had good luck with VHT paints before and they make a wrinkle red that seemed perfect for this without the need to remove the baffles.

I cleaned the valve cover with mineral spirits at first and then wax and grease remover. I then scuffed it with a red scotch brite pad and wiped it down again with wax and grease remover.

The VHT wrinkle paint has very explicit directions on the requirements for the paint to wrinkle evenly. The directions call for heavy wet coats 5 minutes apart. The first coat in one direction, the next 90 degrees to the first and the third at 45 degrees. I followed the directions perfectly and made sure to lay as wet of coats as possible without creating runs.

It can take a few hours for the wrinkles to appear. So I went in for the night and returned in the morning.

I think I applied the paint TOO Heavy!... The wrinkles were heavy and in the corners of the part they looked particularly pronounced. I let it cure a little longer as it can take up to 48 hours dry enough to handle it. I then used an exacto knife to carefully trim out the wrinkles from the corners.

It's hard to tell in this image but I was able to remove most of the corner wrinkles and in general clean up the finish.

I then wanted to remove the paint from the raised letters. I made a crude jig with a piece of plywood and bolted the valve cover to the mill table.

I used a fly cutter to take a few light 0.020" passes.

It turned out pretty good. I may in the future try and redo the wrinkle finish. But I don't want to spend anymore time for now on cosmetics of the valve cover.

We used to use the wrinkle paint, but it is challenging to do well. Now we just use a wrinkle powdercoat. Costs about $50, very durable and low effort.

When I did this to my Miata valve cover, I applied two coats and put the valve cover on the BBQ grill to cure. Pretty sure I took some years off my life from the fumes, but the results were a very durable surface that was hard to scratch off. The paint cured instantly and the wrinkles were a lot tighter than the ones in your picture.

I know our guys used to use a heater as well.

Thanks for the tips guys. I think powder coat might be the way to go in the future.

I've done this in the past and used a Harbor Freight heat gun. Worked great.

That said, i kinda like the REALLY wrinkly look you got there.

I've completed more work that I will post updates on soon (hopefully). But I took some glamour shots with the DSLR that look pretty cool. Enjoy:

The Flyin Miata kit has two options for the oil return line from the turbo. They have a rubber line with barbed fittings which is included in the kit. They offer an upgrade that changes the majority of that line to a hard stainless steel line and only leaves a short rubber section that connects to the oil pan. Either oil return line requires drilling/tapping/installing a brass hose barb fitting/ and a little JB weld to attach the return line to the oil pan. They intend for this kit to be installed with the engine in the car.

I am sure this method works great. Flyin Miata has a great reputation and if there were an issue with this method I am sure they would devise a new method. I decided to go a different route... you could say my engineer OCD kicked in...

Removing the oil pan on a Miata is quiet a chore. With the engine in the car you have to drop the subframe or pull the motor to remove the pan. Since I had the 1.8L engine on the engine stand I figured it would be fairly simple pulling the pan. If you have pulled a Miata oil pan you know even on the stand its a PITA. I removed all the bolts and carefully pried at the pan until it popped free from the block. But it seemed like something was still holding it...

After 15 mins of cursing and searching for a hidden bolt I did a few google searches... See the green looking metal tab on the top of the oil pan flange. That's the windage tray... Mazda engineers thought it was a good idea to attach it with the oil pan and use the same silicone to seal it all up together.

I used a utility knife to score and cut the silicone between the windage tray and the oil pan. Carefully prying the pan away from the windage tray as it was easy to bend the tray flange.

After a little over an hour I had the pan off... I then carefully cleaned it up. Using a combination of de-greasers and mineral spirits I cleaned up the all the oil residue.

Flyin Miata recommends you drill the pan near the front (under the A/C compressor) to lessen the chance of hitting the oil pick up tube on the inside of the pan. With the pan off this isn't an issue and allows the drain line to have a more direct path from the turbo. I carefully selected the spot to drill based on research on the miataturbo forums.

(NOTE: I drilled the pan off the motor!! If you drill it on the motor as shown here you will hit the oil pick up! Which is bad!!)

I then called in a favor... to a friend with a TIG welder.

I had him weld a -10AN fitting to the pan. He is a fantastic welder and it turned out really nice. In the next post I will cover how I made the line to attach to the turbo.

I reattached the pan using Permatex Ultra Grey carefully outlining all the bolts as the factory manual specifies.

Re-installed the windage tray and new rubber seals at the front and rear of the crank and torqued all the bolts in the specified sequence. I used a red paint marker on the final pass to be sure I didn't miss any.

It looks like this will be quite a nice ride when you're done. I'm in for updates.

Enjoying reason this. I'm a bit jealous of your machine shop setup I have to admit.

Any chance of a front/rear weight when it's all said and done?

Looks really nice thus far, subscribing

That's certainly possible. My buddy has scales for his circle track car. We weighed the Miata when I first got it. So I can do a before and after as well. I have the results in the cars binder at home. It was 2200 lbs without driver then don't remember the f/r balance though off hand.

I have a Megasquirt MS3x Plug and Play built by Reverant on the Miataturbo forums that will be installed soon into the car. I would like to use the 1.8L ignition coils at least at first on the 1.8L engine. (may later upgrade to better coils or COP) Typically 1.8L swaps pull the 1.6L coils over and use an adapter bracket. But those cars are using the stock 1.6L ECU from my understanding. The Megasquirt can drive the 1.8L coils no problem from what I read. So I would need to swap connectors for 1.8L coils to the 1.6 engine harness and remove the 1.6L coil drivers. This seems pretty easy... considering even if you swap the 1.6L coils you have to extend the wires to reach the intake side of the head where they mount on the 1.8L motor.

The one hang up from my understanding is the 1.6L coils send a tach signal to the tachometer in the dash. The 1.8L coils do not do this as the 1.8L engine relies on the ECU to send a tach signal. The Megasquirt can send a tach signal to the Tach but I will need to make a connection to the Tach from the megasquirt? Has anyone done this before on this forum?

Or should I just say the heck with it and: A) make a bracket to mount the 1.6L coils B) buy the bracket from Flyin Miata meant to do this?

You're discovering why most people just use the 1.6 coils. They're no weaker than the 1.8 ones as far as I know. And watch yourself with COP, some of them are not as effective as stock but the internet thinks they're cool. Best coils commonly used: Chevy LS.

Does the MS not have a tach output you can route to the tach if you decide to use the 1.8 coils?

You don't need to extend the wires on the 1.6 coils IIRC. You may have to play around with plug wire lengths though. You DO have to extend the wires for the 1.6 CAS when it moves.

It does have the ability to output a tach signal. The spec sheet that came with it specs out what the signal looks like. When I get home I will take a look at what frequency it outputs. Do you know what type of signal/voltage the stock Miata tach is looking for?

The spec sheet for tach output says the MS3x outputs square wave. 33hz at 1000rpm. Does this sound compatible with Miata tach? I am not sure the voltage but I can find that.

I've got more updates I can add once I get more time but I have a quick question perhaps some of the Miata experts can chime in on.

Can the motor be installed with the turbo and exhaust manifold mounted to it? Like as one unit? Most information I have found indicates that’s not possible or at the least doesn't sound recommended. I think I will pull the trans with the 1.6L and install it with the new clutch on the 1.8L and install the whole assembly. Just not sure what to do about the turbo and manifold?

Yes, the engine can definitely with the manifold and turbo installed. That's how we install them when we're doing an engine-out job. IIRC, you can leave the turbine outlet casting on there as well, but you will have to bolt on the rest of the down pipe when it's in the car.

Time for an update. I've accomplished a good bit and I am going to try and catch up on these over the next few days we will see how it goes. So I left off with the oil pan modifications and TIG welding an AN -10 bung...

I have a friend that gets good deals on Aeroquip products so I sent him the part numbers and he had everything in a few days. He recommended their Startlite hose for a turbo oil drain line. I used some Kobalt triple cutters to cut the line to size. Then I fit the fittings on both ends. Per a few threads I found on Miataturbo I used a 60 degree fitting on one end and straight on the other.

I ended up cutting the line twice (measure once cut twice… right?), the first time I left it a little too long for my preference. It still might be a touch long but I am going to try it like this. I still have enough hose to make a few more if I accidently cut it too short.

Next I removed the old stock injectors…

…and replaced them with new Fuel Injector Clinic 650cc units.

They came with pigtails that need to be spliced in. They also offer them with adapters but I wanted to simplify and clean up the wiring versus adding more connections. (It also saves a few bucks going without)

Looks like a nice build. Kinda wish I had gone this route in the first place when I did my Miata instead of piecemeal upgrading from a Greddy kit.

Thanks. A wise coworker of mine (his wisdom gained from years of car projects) told me that if I went with the complete kit from a reputable brand like Flyin Miata I wouldn't regret it. He also said that if I tried to piece things together at some point I would likely end up thinking... "What if I just spent a little more and got the complete FM kit"

Next I worked on the interior. I needed a space to mount my NGK AFX wideband gauge as well as a some switches (data logging, traction control (possibly), launch control, etc), I also wasn't keen on leaving the USB cable to Megasquirt just dangling under the dash or floor so I wanted to mount a jack on/in the dash somewhere. The MS also has the ability to log data to an SD card. However, the SD card slot is mounted to the side of the MS which gets mounted under the carpet in the passenger footwell.

First I ditched the OEM 1.5 DIN Mazda radio and picked up a modern single DIN Pioneer with bluetooth. I still like to drive the Miata to work most days in the summer so a radio is nice to have. I also ditched the pocket below the radio.

I designed a mount for the NGK AFX controller/display, since it only ships with a piece of velcro (lame). I made a simple bracket and 3d printed it on my Makergear M2 printer using ABS plastic. The design allows for it to be mounted in the dash and be pulled out through the front so I can re-calibrate it from time to time without having to pull the entire dash apart to get to it.

Here is the mount after acetone vapor bathing the printed part, which helps to smooth and strengthen the part.

I need to design the mounting plate to fill in the area under the radio that will hold the NGK AFX bracket above, some switches and the microphone for the bluetooth phone. Things started to get a little crowded even with the extra space. So I decided to move the USB jack for the MS and the SD card slot to their own panel. I designed a bracket to mount them under the glove box. This seemed like another fine application for the 3d printer.

I also printed a simple plug to cover the USB jack when not in use.

Mounted.

I still need to finish the design for the dash center panel. I think version one I will 3d print and if it works out well I will probably try and machine something nicer.

Very cool build. Looks like you have some nice tools at your disposal

Thanks. Yeah I've been stock piling tools over the last few years and delaying car projects. Now I am finally getting to use them for some cool projects.

I compression tested the old motor before pulling it so I would have that info when I go to sell it.

All 4 cylinders were spot on to the factory spec of 192PSI... not bad for a 21 year old motor with nearly 100K miles on it. (It did get a refresh of the head a few years back though)