So i finally got my Kmiata Big Tube Header, Im pushing forward with the project trying to overcome each obstacle as i hit it.
I think its fair to say that the only K swapped cars that i have seen successfully running, have been done by Honda guys who bought Miata's, rather than Miata guys who bought Honda motors. Making things worse is that this swap has been designed around the NB chassis. So NA guys are kinda in the dark.
That being said, David from Kmiata has been very helpful via email in helping me resolve any issues i have come across and i have been providing him with some feedback and constructive criticism (ranting).
For anyone doing this swap in a NA chassis, I'm going to list was i used for my conversion harness wiring, as well as some other things that are not in the directions that i feel miata guys may overlook.
CONVERSION HARNESS WIRING
For 1993 Miata, may work on other NA's
Kmiata conversion harness Miata harness
12v Constant red------------------- white/red wire (btw fuse to stop fuse)
12v Switched orange---------------black/white wire (ignition switch to cigar fuse)
Fuel Pump green------------------- blue/red wire (circuit opening relay)
Tach Signal black------------------- Yellow/blue wire (ignitor pin H1 on cluster)
CEL/MIL yellow--------------------- yellow/black wire (pin 1C on cluster)
Starter Signal large blk/wht ------- Violet wire (from start sig fuse)
Oil Pressure brown-------------------Yellow/red (pin 2b on cluster)
Fan Control blue---------------------Black/Green (cooling fan relay)
I removed the main relay completely as well as all of the engine wiring, ABS,SRS,A/C,CRUISE,PS. The harness was completely stripped and de-pinned and re-loomed. I spliced the two Black and White wires that That go between the engine fuse/main relay and cooling fan relay together, you have to pop open the engine bay fuse box to do this)
Also i used the factory cooling temp sender for the miata gauge, I put this in the K-tuned water housing on the back of the head and ran a wire from the sender to pin 2L (black/blue wire) on the cluster.
I ran most of these wires with the harness stripped, and had them looped in the passenger foot well to be connected to the Kmiata conversion harness.
If you are running a TSX K24 motor, and using the 02-04 RSX harness like the directions say, you need to change the plugs on the crank angle sensor, or change the sensor to a RSX one, IF YOU CHANGE PLUGS YOU MUST CHANGE THE PIN LOCATIONS.
Heres is the diagram
Next, the factory O2 sensor plug is on the conversion harness, I overlooked this until this night, I bought a PLX wideband gauge anyways because i did not have the factory sensor. The factory (upper,primary) sensor is wide band already. Its the easiest way to go.
If you want to use a after market gauge in conjunction with the OEM one, You need to wire the gauge in per these instructions.
If you want to use a aftermarket gauge only, You must wire the analog input cable. For instance, my PLX has a 0-5v analog output that i wired to the Analog input-0 on the Kpro.
You must select PLX wideband in the Analog input parameters menu, you must then go to closed loop settings and deactivate the OEM O2 sensor errors. And select External Wideband, and the Analog input your using.
Next go to your wideband settings, and change it for the analog input as well.
This should work to run the car without the OEM sensor.
Hope that helps anyone doing the swap in a NA, feel free to PM me with any questions.
Heres some pics of the Header.