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Your standard "I have no idea what I'm doing" build thread.
In early 2019 I decided that I wanted a fun little manual car and so the hunt began. At the time I had a 2018 EX-T Civic Coupe (RIP) and a 2017 SR5 Tacoma. Being rather young and impressionable I decided that obviously rear wheel drive is the way to go so I hit craigslist. The first Miata I tried out was a beat-on ratted-out NA that rapidly scared me away due to varying levels of what was being used to hold it together (zip-ties, sheet metal screws, duct tape, etc.) The one I stumbled upon was an absolute peach with a whooping 200k on the clock. I ended up picking it up for about $2200 and had a blast all summer until I had to travel for work. When I finally got home I decided I wanted to go faster and after determining that an ls swap would be awesome, it just wasn't monetarily reasonable. For the next year or so I searched the internet and stumbled across someone selling a complete MSM engine for $2000. I begged the wife and after promising a gazebo and a patio she agreed that I could get it. We went to look at the engine and this guy was really down to earth. He was working on a turbo NA running on a hydra system I think. I ended up getting the engine, trans, wiring harness, computer, hot side piping, cold side piping and RC Engineering 550cc injectors all for the $2000 he was asking. As an added plus the former Miata that housed the engine had gotten slid into a tree early in its life so the new engine/trans only have about 42k miles on them. As of right now I have also gotten an MS3Pro PNP so I didn't have to re wire the entire car to run the new setup. This thread is more of just tracking of ideas and how the build is going.
Prior to swap:
Upgraded wheels from stock to black 15" Konig Helium with Dunlop Direzza DZ102 tires
Found a factory hard top and had it painted to match the car
Plugged in the MS3Pro and got the stock BP-4W started and running.
Day 1
I'm doing this in the car port next to my house with simple hand tools so its going to be a bit of an adventure. I unplugged and removed the whole harness from the engine. I also removed the 2 vacuum lines, the fuel line to the engine and the air box. I need to figure out a good way to drain the coolant without getting it everywhere before I touch that. I unbolted the A/C compressor and the P/S pump from the engine because I would like to try to keep those systems intact. I was unable to get the pictures to upload to this thread but kept them in my album.
New motor/trans Vacuum line 1 End of vacuum line 1 Vacuum line 2 End of vacuum line 2 Plug from starter and from oil pressure sensor? Alternator wiring AC compressor bolts Power steering bolt Fuel pressure regulator bolts
Day 2
As those Aussie guys say, first step is jack up your car.
Today I started on the work underneath on the exhaust which is already broken and obnoxious. I had to look up where the o2 sensor was connected because it was siezed in the pipe.
Slowly chipping away at things that attach the engine/ trans. With the exhaust removed that leaves coolant, heater, driveline, and the clutch line so I moved on to the coolant and heater hoses.
After the coolant was all drained I removed the upper and lower rad hoses as well as the hoses going to the heater core. Also got the sneaky little grounding strap under the heater core. Last thing for today was to unbolt the engine mounts from the frame and the brace from the transmission.
So at the end of day 2 all thats holding the engine in is gravity, with the drive shaft and clutch lines still attached.
Day 3:
Today was a late day at work unfortunately but I was able to steal a standing lamp to let me work later. The first thing I attacked was the drive shaft. I wiggled my way under and proceeded to destroy a knuckle by smashing into the broken exhaust.
The last thing left was the clutch line that was disconnected up on the firewall from the hard line. I hooked up the crane just for motivation.
Seeing that gave me some unnecessary motivation and I decided to start pulling the engine. I removed the whood to give some extra needed room.
As much as I shook the transmission would not unstick from the brace so it got fully unbolted from the rear diff as well which did the trick.
Because I don't have a load leveler the wife worked the jack while I crawled underneath and pushed forward while pulling down the transmission tail to keep the shifter from getting caught. Finally the motor was far enough forward so I could crawl out and help pull it away from the car.
I started the morning with the engines next to each other, piece by piece I transfered accessories and their brackets. The AC bracket needed some massaging and I'm not entirely sure the NB1 compressor is going to clear the coolant out let but I'm sure going to try.
While moving the alternator I noticed something a little when comparing the hardware.
I tried to use the new hardware but the threads on the alternator are so messed up that I couldn't use the shiny new bolt and my cheap garbage Chinese thread tapes wont fix them so the crappy one went on the new engine.
After doing the research I know the ignition set up is better on the msm but I'm trying to not mess up the wiring loom and just do plug and play to an extent. Thus I'm left with the NB1 spark system until I can make a loom to use the semi COP msm setup. That also required cutting up some of the coil bracket because the pretty red valve cover has a small protrusion on the rear passenger side.
The last thing to get swapped over was the speed sensor from the 5 speed so the speedometer will still read correctly.
With that done the engine itself is ready to go in. I have a load leveler coming tomorrow to make it easier to get the new engine in. A little deconstruction showed that with some modification to the headlight and radiator ducting the cold side piping will fit great.
At the end of day 4 I'm ready to throw the new engine in and start plumbing.
Day....unknown.
Got the new recirc and put it on. Had the great idea to try and fire it up. First try.......nothing but solenoid ticks. Turns out I forgot to put grounding straps on. When that was fixed it fired right up. More updates soon.
Got the car about 90 percent back together and went to start it fully plumbed and filled with fluids. It started ok but something was off, after a few minutes I shut the car off and pulled the keys out of the ignition. As soon as the ignition was in the off position the fuel pump relay started rapidly cycling. I freaked out and ripped the cable off the battery. While looking around I found the cable to the alternator was just barely making contact with the stud. I put the cable on and hooked the battery back up. The relay kept cycling, it would stop when the car was in on though. I started the car again and watched battery voltage which just kept climbing. Voltage would jump if revs went up at all and wasn't steadying out. I shut the car off before I got to 16 volts noticing that the ecu wasn't sending any signal to gate the alternator. After a bit of very helpful back and forth with the folks at DIYAutoTune and some multimeter shenanigans I found that power was back feeding from the alternator through the ecu. The new alternator will be here tomorrow (May 7th). Then I can finally torque things down and get to tuning.
New alternator went in without a hitch and I got the wideband wired up, its in the stock spot on the MSM exhaust for the rear o2 sensor. Some people were saying that the bosch 4.9 that comes with the AEM UEGO kit was very fragile when close to the turbo. I used the CAN inputs so that the ECU sees what the gauge is reading. Next things will be putting the bumper and hood back on.
The vacuum leak I thought I had was just the BPV is open a bit at idle, apparently enough to supply enough air for the car to run. I was able to put the bumper and hood on for a first test drive but my under tray is to far gone to be of use. Finally was able to make boost, its only taken 2 years of owning the car and 2 more months of timkering to do it. I'm looking forward to tuning it and driving it this summer.
Got the car about 90 percent back together and went to start it fully plumbed and filled with fluids. It started ok but something was off, after a few minutes I shut the car off and pulled the keys out of the ignition. As soon as the ignition was in the off position the fuel pump relay started rapidly cycling. I freaked out and ripped the cable off the battery. While looking around I found the cable to the alternator was just barely making contact with the stud. I put the cable on and hooked the battery back up. The relay kept cycling, it would stop when the car was in on though. I started the car again and watched battery voltage which just kept climbing. Voltage would jump if revs went up at all and wasn't steadying out. I shut the car off before I got to 16 volts noticing that the ecu wasn't sending any signal to gate the alternator. After a bit of very helpful back and forth with the folks at DIYAutoTune and some multimeter shenanigans I found that power was back feeding from the alternator through the ecu. The new alternator will be here tomorrow (May 7th). Then I can finally torque things down and get to tuning.
Can you elaborate on the "new" alternator you had to order..? Part #, amps.? Etc.? I'm now on the 4th alternator for my '04 MSM-NB3 and the 3rd AGM battery as well... I believe the 1st replacements of both of these were "wrong", but I have no way of knowing as I didn't write down the OEM parts numbers before handing them over for the core charge replacement..😭
Sorry for the super late reply, my work has had me away for a few months. I just got a Bosch replacement from Autozone, nothing fancy. (Bosch Alternator AL4226X) Says its a 70 amp alternator. If you need I still have my original alternator in a scrap pile that I could look for but its off the 99 NB1 1.8.
Before my work had me leave I tried to drive the car to work. It was only about a half hour drive and not really any traffic so I figured it would be fine. I was about a mile from the parking lot when I heard a dreaded *tink* of something falling off and then the car just died. AFR did go lean or rich and the oil wasn't a milk shake so I knew the engine wasn't toasted. Unfortunately I knew I had to leave in a few weeks so my lovely wife came and picked me up off the side of the road. We went to the local uhaul place and rented a trailer. I was underneath the dash trying to bypass the clutch safety switch so I could use the starter to get it on the trailer but fortunately some nice people stopped and helped me push the poor car onto the trailer. Then it just sat in my driveway for three and a half months. I started looking into it finally after getting home last week. The battery was dead but a slow charge brought it back to life. Unfortunately the car was still not starting. I tested all the plugs for spark using the built in test mode in Tunerstudio, all plugs had spark. I tried some starter fluid to just get it to fire but all that happened was a weak pop every couple seconds while cranking. I took the plugs out again and could definitely smell raw gas on the tips. So there was spark, there was fuel and I took the intake boot off so I knew it definitely had air. So 1+1+1=3 and car should go bang right, but still nothing. I gave it a rest for a few minutes, mostly because I was mad. I went back to the car after a nice video game break. I tried cranking and taking a log file but it looked super janky, the RPM signal was surging from 0 to ~190 which is nowhere near what it was actually doing. The tach was also showing 0 while cranking. I know the car has it's three basic food groups but something is still wrong so I did some forum diving. I found that some people had issues with the crank angle sensor being to far away. I grabbed a spark plug gapper to check if it was anywhere near close enough. The Mazda service manual calls for .5-1.5mm (0.020-0.059in). I tried to use the starter tap trick to get it but it did way more of a rotation than I needed. I felt around the timing wheel and found the nearest tooth, using some end wrenches I put it where the head of the sensor was and used the feeler gauge. The whole feeler gauge went right between which was weird because looking at the tooth that was close before I bumped the starter it looked super close. Upon closer inspection the culprit was found. During some spirited driving (and perhaps some oversight on correct tightness on a bolt on my part) the bolt for the alternator tensioner bracket to the engine block had worked its way out. Of course that wasn't the only problem, I've never been really good at math but I know that using my fingers I can make it to about nine and a half but this four tooth timing wheel definitely only had three teeth. Looking closer there was a pretty obvious gouge where the alternator tensioner bolt had gotten stuck and taken off one of the timing teeth before dropping off the car. Fortunately I still have the original engine so I was able to canab the timing wheel from it and hazah, the car fired up on the first try.
wow, good for you hanging with it and sorting it out - now we know a alternator taking a tooth off makes a 'tink' sound.
Should be really fun once you get it reliable.