So I guess it's finally time for a build thread! I've been hanging around here for a long time I bought my Miata (99 base model with the PEP package) from a member here in 2013 and always intended to go turbo. My oldest son (in elementary school) dubbed it the "slow car" and thus it has been named since. The previous owner had run a supercharger at one point so it came with some goodies (I/H/E, MS2E, and the AGX FM suspension). AC wasn't working when I bought it so instead of fixing it I did a full delete. Over time I've made a few other little modifications including GM coils on homemade bracket for spark, RX8 injectors, DW200 fuel pump, 949 brake lines and a few other little things. About two years ago I acquired a turbo kit from another member consisting of an Artech manifold, T3 chinacharger, and other components. I've been sitting on the turbo kit for almost two years now (I've got three kids and a busy job so i rarely have time to wrench like I want). Then came this past Friday when I drank a little bourbon, went out to change the fuel filter and ended up starting a turbo install!

My time is pretty limited so I've been working a few hours each night after the kids are in bed, which means slow progress. I also did a looped lines PS delete which I spent more time fiddling with than I anticipated (story of every car project ever). As of last night, I've got manifold, turbo, EWG, and downpipe all bolted up. Pictures of the current state attached (please excuse the dirty engine bay). Unfortunately I have to get the car back on the road Thursday (it's my daily for a few more months) which is a bit of a constraint, and will require some issues to be revisited later. A few challenges I've run into so far: First, the oil pan was tapped by the previous owner and is shifted a little bit off from the "standard" location, so the oil drain line included with the turbo doesn't match up, I'm planning on an additional 90 degree AN fitting which should get things pretty close. The guy I bought the turbo from put together a nice cold air box for the intake. Unfortunately, the piping I have isn't going to get it in the correct location for that to work, I'll get some additional piping to make this work later. Also, I spent a while planning and starting to a fab an intercooler mount using the OEM AC brackets as a mounting location, but I realized that the MSM intercooler piping I have isn't going to work in that location without more modification than I have time to do right now. As a result, I'm going to run the MSM piping and intercooler in the same manner as the previous owner of the turbo, until I can order additional piping to get my larger intercooler to work. I will probably go with entirely new piping and scrap the MSM stuff. That also means I'm going to leave off the air guide and undertray (I don't want to cut them up now when I now the pipe routing is going to change a bit). Hoping I don't have any cooling issues, but the reading I've done seems to indicate I'll be fine on the street.

While the change in intercooler plan isn't ideal, it will save me some time, the guy I bought the turbo from even included his mounting bracket for the MSM turbo so that should go quick. So, remaining tasks to get it back on the road include: install intercooler and piping, Get oil lines hooked up. Route all my vacuum lines, Install deezums catchcan. Get the bumper back on. Tune.

My initial plan is to run the 7 psi wastegate spring, get comfortable with the tune, and increase from there. Mid term plan is to get just under the limit of stock rods and 5 speed on E85 (because i have a station nearby, so why not!) I have dreams of getting on the track, but it's probably not going to happen any time soon the way my life is. So mostly a street and occasional autocross car. In a few months I'll be getting a boring sedan as a daily, so I'll be able to tinker a little more freely. I really love building stuff, so for me, that is a huge part of the enjoyment of this hobby, maybe even as much as driving. This is an awesome forum, the knowledge here is vast and has been incredibly helpful in every step of this process. Thanks to all of you!

Path forward once turbo install is done
Near term stuff
Bigger intercooler with piping and reinstall modified undertray (I have the intercooler, need piping)
Big sexy injector goodness, because RX8 injectors suck (fuel injector clinic 900cc in my possession and FF install kit on its way)
Skunk2 TB (In my garage)
Coolant reroute (skou spacer in my garage)
Aluminum radiator (probably a cheapie)
Bilstein Coilovers (also in my garage)
Wheels and sticky tires (waiting until this is no longer my daily)
Replace my leaky top

Longer term
Motor (my rings are tired, I have lowish compression across all 4, I'll probably swap in a healthy VVT motor, but if my toy budget is feeling flush I might rebuild with forged internals)
Build MS3x (especially if i get a VVT motor. I'd also like the ability to do flex fuel and EBC)
Roll bar and aluminum race seats bolted to the floor (I have tall guy problems)
Proper ducting for intercooler and radiator
3" Exhaust from DP back (currently 3" DP > 2.5" Exhaust)

Dream Build
Built motor, 6 speed, EFR, BBK, XIDA, ALLOFIT
Or maybe LFX swap.

 

In for more, 'I was going to do xyz, but then I drank bourbon' moments!

Out of curiosity, do you have numbers for compression?

 

It's been a little while, but I think they were all 125-135 on the cheapo harbor freight tester. A little oil on the piston got them all up to around 150 and it burns some oil during regular use, so the signs point to the rings being toast. A perfect engine for turbo! Hopefully it lasts until I get my new daily, then a new (used) motor will be high on the to do list.

 

Made progress last night. Oil lines are installed, the 90 degree bend worked well to get the oil drain lined up (Pic 1). MSM intercooler and piping are installed. I got the wrong size vacuum line so I need to get back to the auto parts store to finish the vacuum lines.

A question on the vacuum sources: I know the usual approach is to tap in to the line on the back of the intake, however my understanding is I have a bunch of vacuum stuff (charcoal canister, oem barometric/boost sensor, egr stuff) that I don't need ( I want to keep VICS hooked up). Would one of those various sources be better than tapping into the brake booster line? I can't seem to find details on it, other than braineack saying at various times that the ports at the front and back of the IM have a lot of turbulence and therefore less ideal for pulling MAP signal. His suggestion was always to tap the fpr line, but I don't have that line on the 99.

Also, I need to make block off plates for the EGR pipe and valve connections on the back of the intake manifold and was planning to utilize some Home Depot racing flat bar, however, I forgot to measure the parts or bring them with me to work today. Does anyone know offhand what width bar i need to cover the openings? it looks like maybe 2" wide, but I'm no good at estimating dimensions like that. Basically, can anyone tell me the dimensions these: https://miataroadster.com/miataroads.../i-445413.aspx

 

Well, I now haz trubo I went ahead and tapped the brake booster for MAP signal, but if anyone has input on a better location please let me know. I just used some leftover aluminum I had in the garage for the EGR blockoff. It ran well today, Holding boost at 6psi (wastegate pressure). My IAT sensor isn't working right, so I need to figure that out, maybe calibration or wiring.

One kinda significant concern, I'm getting a ton of vibration in boost, going 80mph at 4k rpm was rattling the dash, it begins to show up around 3k. Does this likely indicate a bad shaft in the turbo?
*Edit: Looks like I need to check for downpipe/chassis contact as another potential source of vibration.

I already want to turn up the boost!

 

So I think my down pipe may be contacting my steering linkage at certain RPMs causing the vibration. It sits pretty close, and it was previously hammered a bit to clear.the linkage. I need to check a little more and make sure there's no other potential contact points. What are options for remedying this? I have the supermiata race mounts in the garage, would that help (I'll probably try this in the "hybrid" configuration). Would an exhaust brace help? Something similar to what FM used to sell, or the options discussed here: https://www.miataturbo.net/diy-turbo...-doesnt-62045/

 

Talking v bands here.
I always want to adjust the downpipe so it is even between the motor and steering linkage, but it always gives the vibration.
I try to remember (and did last time) to set the downpipe close to the motor, not in between. The reason is the pipe moves with the motor. Aidan recently did some nice bracing in his thread IIRC.

 

Unfortunately I'm not one of the cool kids with v bands. I think I'm going to try the stiffer mount on the driver side and come up with a down pipe brace. I might try using this thing to make a brace:



It's designed to attach lights to a roll or Bull bar, so it might not stand up to the sort of vibrations that will be experienced in the exhaust, but the shape should make mounting real easy, especially since I don't have a welder to easily Fab something custom.

 

I put my pipe in a vice and flattened it a tiny bit, also as proved on road kill a few hits with a hammer show no ill effects
also good start to a build thread, comforting to know later in life I can be burdened by things like kids and still make time for turbo Miata's

 

A few goodies came in the mail today:


$8 ebay ball and spring MBC, I will go with a megasquirt controlled EBC selenoid at some point, but for now the MBC will work. Hoping to spool a tad better than wastegate only and run a bit more boost, probably 10 psi or so for now.


Flow Force BYOI kit for EV14s. I bought some fuel injector clinic 900cc ev14s a while back on the forum. I thought they were only a few orings away from Miata fitment, but turned out they didn't include top hat extenders either, so I decided to just get this whole Flow Force kit. Now I'm ready to install injectors.

I also talked to DeatschWerks today about a warranty replacement on my fuel pump. I bought a DW200 pump a few years ago cause my oem pump died and then a few months back the DW200 quit on me. I bought a local parts store pump to get the car back on the road and am now hoping to get the DW200 pump replaced under warranty, I've just been too lazy to get the warranty process started before now. I meant to do it within the return period on the parts store pump, but that didn't happen. Once i get the fuel pump sorted and injectors installed I'll be switching to E85

 

Made some progress, broke a few things, etc... Boost controller installed, and tweaked a bit, although I haven't had a lot of time for tuning, but man, turning things up to 10-12psi was a blast. I think I have it dialed in to around 10 psi peak now.

I've been having issues with my IAT sensor, actually the wiring for the sensor. I've seen similar erratic values from 2 different sensors. It'll be reading a normal reasonable value and then jump very low and then go back up. I determined jiggling with the wiring harness at the megasquirt seemed to help. Pulled the ECU to look for loose wiring and potentially re-solder the connection. I managed to break a few of the other solder joints at the wiring harness side of the db37 pigtail. This has happened before, and I think I'm done with trying to mount the ecu in the stock location. Every time I remove it or put it back in I have to jam stuff around and this is the second time I've had to resolder some of the pins. If i ever get around to building a MS3X it's going to make have a longer db37 and sit behind the glovebox.I might do it for my current unit. Anyway, re-soldered stuff, car is running, IAT is still being weird, so that didn't get fixed, and now my alternator isn't charging!

The alternator is about a month old,, so it could just be a bad unit, but given my other wiring issues, I'm concerned I may have messed up the alternator voltage regulation circuit (by knocking some connections loose). It's a braineack built megasquirt with an external box for the alternator regulator circuit. Based on my research I believe brain used the regulator circuit from Jason and with that circuit the alternator field wire should measure over 5V when the alternator is intended to be charging, and around 3V when the alternator is intended to not charge. Can anyone confirm this? Paging @Braineack...

Also, I was doing a little digging on electronic boost control. Since I no longer have AC on my car, I think I can pretty easily modify the AC out circuit I have to drive an EBC solenoid, so implementing that might be moving up my to do list. Even though I haven't had it long it's easy to see the disadvantage of the manual ball and spring boost control in the logs. I also need to move my wastegate pressure reference to the cold side of the intercooler (it's currently at the turbine outlet).

 

I don't remember building any MS2s for NBs other than DIYPNPs.

are you sure i built it? I made custom PCBs using Jason's circuit for a while (maybe 20 units) but I installed them inside the case.

 

It was for 94mx5red (I bought the car from him), apparently it was an upgraded MS1. Details here, including lots of pics of megasquirt and alternator control box innards: https://www.miataturbo.net/megasquir...-my-eye-68022/

 

It looks like I do have issues with the circuit. I tested the field wire at the alternator plug and it was showing 3V whether the car was off or running. I also tried flipping the output in Megasquirt to always on (it was set to on above 300 rpm) and that also had no effect. Looks like I need to pull the megasquirt and check connections again. It has been working for years without issue, so it seems likely I messed it up last time I pulled the ecu. Hopefully it's just a matter redoing a connection that has come loose.

 

Well, I took apart the MS. Checked for loose connections or burned out parts, everything looked pretty darn good. I put it all back together and back in the​ car, and now the alternator is charging again... A nice strong 14.2v. it is always a little disconcerting to fix stuff without actually fixing anything, but I guess I'll take it, and keep a close eye on my battery voltage. I also moved Ms location to right under the steering column. I think that works better getting my db37 pigtail to fit without smashing things around. Currently held in place with high class harbor freight racing "hook and loop". I think I might try to grab something a little more secure. I guess I'll probably have a singular ECU mount for sale here soon. Still haven't got to do much driving/tuning with the increased boost. Looking forward to a bit of that tomorrow.

 

Welp, I've been drinking bourbon, so I guess it's time for an update. Not a whole lot accomplished, other than buying some parts. I've ordered an ebay intercooler piping kit which should arrive next week, at which time I'm hoping to ditch the MSM intercooler and go with the larger unit I have. Plan is for 2.5" charge piping throughout. Lack of ac and power steering should make this achievable. I've also acquired all the parts to finish my coolant reroute utilizing the skou spacer I bought a year or two ago and a kia waterneck, etc. At interstate speeds my coolant temps have been creeping to 215-220 (factory undertray is currently removed and will be reinstalled once final intercooler setup is in place). I've been pretty cautious to take it easy on boost when my coolant is up at those temps. I'm also hoping to install injectors this weekend and switch to e85 at my next fill up Downpipe bracing and stiffer driver side motor mount are also high on the to do list, although I don't know if I'll get to those this weekend. I realize this thread is useless without pics, planning to document in detail the upcoming work so stay tuned.

 

Additional progress: I was prepping to install injectors last weekend and realized the fitment was a little different than I anticipated (more here: https://www.miataturbo.net/engine-pe...pics%2A-92703/) Eventually I got the injectors together, (Note: after trying to get the plastic o-ring retainer thing off with pliers, I used a soldering iron to melt through the ring as noted here: https://www.miataturbo.net/miata-par...s-83178/page4/ that method worked well).


I installed the injectors last night (sorry, no pics). I removed the top half of the intake manifold to get access (this would be way easier with the whole manifold off) and one thing i noticed upon reassembly was that it was difficult to get the upper manifold piece back in place because the manner in which the fuel rail spacers change the rail location. I had to whack it a little bit (with my hand). Once seated, it seemed to have clearance, and I imagine this would be a non issue if the whole manifold was removed/reinstalled as a unit. I adjusted required fuel and got it running pretty quick. Then drove to the gas station and did this:




Added about 30% to my VE table and off I went. The tank probably still had a gallon or two of 93 octane, so I'll plan to retune a bit after each of the next few fill-ups.Ran well on the way to work today, although my annoying alternator charging issue resurfaced. Jiggling the box that has the circuit (outside the MS box) is currently the fix. I may get one of the westfield mx5 boards to build. I like that it has the battery light and also it "fails open" such that if the connection to MS is compromised (which is what I think I'm dealing with now) it will continue charging. What i currently have requires a signal from MS to charge. I got my intercooler piping and I'm hoping to get the bigger intercooler installed and the undertray back on this weekend. I've been having some pretty high coolant temps (~215F) during interstate cruise. I need to get the reroute done too, but both of those in one weekend is not going to happen.