Miata Turbo Forum - Boost cars, acquire cats. - 95 Miata with stock MSM turbo setup Build

I’ve been a member here for a few years, lurking and slowly building up the courage to turbo my Miata. The first one I owned was a red 92’ Miata with a Greddy Turbo kit installed by the previous owner, which was the first car I’ve ever bought (in college at the time) and was too immature to appreciate what I had. Flash forward 5 years later, I’m still immature and too dumb to turbo a car, but I did it!

I saw a Mazdaspeed Miata factory turbo setup that was “basically bolt-on” for 94-2005 and in good condition for $800, which included the turbo, exhaust manifold, MSM injectors, MSM waterpump inlet, MSM oil pan, entire intercooler set up, downpipe and cat, and misc.

I had an 8:1 disc Vortech FMU, ebay intercooler, and a box of intercooler piping, couplers, and clamps in my possession for a few years and decided I was ready to take the plunge. Well here is my turbo build. It took 3 and a half days, greasy, bloody hands and fingers, in a parking lot at my apartment complex, 5 angle grinders, a drill, 30 feet extension cord, and a prayer. I retained all PS/AC/Cruise Control.

1. First stare at your engine bay and muster up the courage to turbo and go through your mind what you are about to do. Lay out all the parts in the parking lot for all the people to see.

https://www.miataturbo.net/attachmen...ine=1396092815

2. Unbolt and remove all the unnecessary things that get in the way of the turbo. Use a lot of nut busting penetrant. (I decided to do a EGR delete, charcoal canister delete) Make sure to fill up on 93 octane gasoline. I retarded the ignition timing to 8* BTDC.

https://www.miataturbo.net/attachmen...ine=1396092815
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3. I decided to drill and tap my oil pan after I learned how much work it takes to change an oil pan in a Miata. Change the oil at the same time (Mobil 1 5w-30 on sale). Cap off the oil drain port and see if you have oil pressure. I didn’t have the right size drill for the tap/thread kit from BEGI so I improvised.

https://www.miataturbo.net/attachmen...ine=1396092815
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4. Chop off the O-fittings off the oil return line and water lines for the turbo (where the hollow bolts would’ve gone) with an angle grinder. Hoses and clamps will be fine for these.

https://www.miataturbo.net/attachmen...ine=1396092815
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5. Install sandwich plate oil filter adapter (M20x1.5mm) and 40“stainless steel oil feed line (M10x1.5mm).

https://www.miataturbo.net/attachmen...ine=1396092815

6. I decided not to use the MSM waterpump inlet because the bracket used on it will not fit over the exhaust studs and will require me to do entirely too much work to make it fit. Instead I just used my angle grinder to hack off the neck of the existing waterpump inlet so it will not interfere with the compressor inlet. I then reused a part of the coolant pipe that goes to the lower radiator hose and did a FREE reroute. Now I have the proper clearance for the turbo and manifold to mate onto the head.

https://www.miataturbo.net/attachmen...ine=1396092815
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7. Switch out the stock fuel injectors with the MSM injectors.

https://www.miataturbo.net/attachmen...ine=1396092815
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8. Switch the stock spark plugs for the ones that are 2 steps colder (BRK-5 I believe)

9. Install FMU.

https://www.miataturbo.net/attachmen...ine=1396092815

10. Cut off/grind down the protruding parts of the stock fans’ shroud/guards that will interfere with the intercooler piping and charge pipe to throttle body.

11. Test fit exhaust manifold/turbo, and bolt it on. I used the MSM exhaust manifold gasket and it fit perfectly on my 95’. Dremel the ports if you want it perfect. Bolt on the oil feed; hook up the oil drain, and water lines.

https://www.miataturbo.net/attachmen...ine=1396092815

12. Install intercooler and piping, I inverted the compressor outlet by literally bolting it the other way for fitment purposes. I used a flex pipe from Pep Boys (it’s reinforced with a metal coil inside) so you can flex it into any shape. Make a custom bracket. As for the idle control speed valve, you can use the stock MSM throttle inlet tube. Just remove the air temp sensor, and clamp an elbow that reduces to a 3/4” diameter which will mate with the stock ISC valve hose.

https://www.miataturbo.net/attachmen...ine=1396092815
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13. Bolt on the downpipe and cat and exhaust of your choice.(I’m running just the stock MSM downpipe and cat) Install boost gauge.

14. Say a prayer and start the car. Mines started with no issue, check for leaks, and test drive around the parking lot. I drove 2000 miles so far, (installed it Jan 3rd, 2014).

My impressions: Whoa! The sensation is noticeably different. The car feels violent! Once I’m in boost, the car just pulls! I noticed that the turbo spools up around 2800 RPM with ½ throttle. I haven’t heard any knocking, but it’ll misfire every so often. It idles at around 900ish rpm. No boost/oil/coolant leaks yet. It’s definitely daily driverable. When not in boost, it behaves completely stock.

I was extremely afraid to push it to the limit due to the fact that I have no engine management(except for the FMU), the clutch is original, and I don’t have a wideband to tell me my AFR so I will continue to drive it 90% until I can MSPNP or get the 305cc supra injectors like I originally planned. I’ll post a video sometime this week. I’m a registered nurse, and an Army Officer so I really have little free time, but my Miata brings me happiness and I’ll continue to make her my hobby until we run out of dino-juice!