Megasquirt 3 install on 1.8 swap 93
 

Hello, I made this post on MiataForum.net, but realized i would probably never get a useful answer, so i thought it be better to make the post here.

I have a 93 Miata with a 94-97 swapped na8 engine. I didn't do the swap, but it was done with the Flying Miata kit, seemingly following these instructions: https://www.flyinmiata.com/support/i...sc/1.8swap.pdf

I have a 1.6 water neck, 1.6 throttle body, 1.6 coils. I ordered my Megasquirt 3 kit for diyautotune, and i'm trying to prepare before it gets here. I'll be following the truboKitty guide here https://trubokitty.com/#/

One issue i for see having is the 1.6 throttle body is ridiculously close to my Mishimoto radiator. So i picked up a NB throttle body as it has a better tps anyway. as far as i know it _should_ mount up, but it looks like the connector won't quite match up. My na6 harness has a three prong connector for the TPS, and a two pin connector that i can't quite figure out where it will be going with the new throttle body.

I also have a problem where my stock fan on the mishimoto radiator interferes with my Flying Miata sway bar. Anyone have any ideas about this?

One last question i have is not really a huge deal, but my car was once fitted with AC, so the hole i would use for the map signal vacuum is taken already. I'm sure i can just drill a new hole, but if anyone has an existing solution that i just missed, please let me know.

Thanks so much in advance
Connor

Answering my own question here in case anyone in the future stumbles upon this post.

I had to buy a NA8 crossover tube to fix the clearance issue. I haven't installed the NB throttle body yet, but i was able to find the NB throttle body connector so i'll have to splice that together when i do install it. I also had to buy some ebay special low-pro fans.
Also the NB throttle body having two connectors was just incorrect information.

See above. Bought ebay ricer style low pros.

There is in fact another port behind the ABS equipment on the passenger side of the car. Was easy to pop the grommet out and drill out a hole to feed the MAP sensor tubing through.

More Gotchas:
1) I installed the Super Miata coolant reroute and it was a nightmare. This kit is incredibly difficult to fit on a 1.8 swap. It REQUIRED a different crossover tube as the NA6 crossover leaves absolutely zero room for any coolant hose. I ended up joining the long coolant hose to a
Mishimoto upper coolant hose.

2) Making the patch harness from the ms3 to the miata wiring was straight forward, but i wish i had made mine a bit longer as many of the wires need to cross over each other. I may build another connector in the future as im not 100% happy with how mine came out.

3) I actually missed a couple parts when assembling the MS3. I had to check over my work 3 or 4 times before the car would actually start

4) I had planned on installing my wideband o2 sensor before my standalone, but the AEM X-Series does not support narrow band emulation, so it would not run on the stock harness. Along with this the X-Series required wiring in an extra sensor ground to read accurately.

5) I had to throw a 1k resistor on the binary tps to keep it from forcing the MS into flood clear mode.

6) i had to load a base map for a 94-97 1.8 engine and change a bunch of settings to make it work with 1.6 wiring. I suspect the opposite method would have worked as well with enough effort.

7) 93 cars in california are wired for sequential injection already. This is not on the trubokitty guide anywhere, so i actually added wires to my options plug that i did not need at all.

Anyway, i hope this helps someone out in the future as i had a lot of trial and error with this particular setup. Still building my own ECU was a fun experience and i save quite a bit of money over buying a PNP.