mrolo74

I have a 90 miata with a 1.8 swap and im turbing it. When i go to order megasquirt do i get the 90-93 setup cause thats the computer in my car right now or do i order 94-95 setup cause thats the year of my engine. I'll probably get flamed for this but i wasnt really sure.

Braineack

iTrader: (62)

get the PNP that matches your harness and sensors. in your case the 9093. you may need to modify it to see the TPS signal.

mrolo74

yeah thats what i meant im going to get the pnp but wasnt sure witch one. but thanks for the anwser ill get the 90-93 pnp and modify it from there thanks again.

Joe Perez

iTrader: (8)

You definitely want the 90-93 version, because that's what matches the ECU harness in your car. I am assuming that as part of the 1.8 conversion, you moved over your old 1.6 injector harness and are running the 1.6 coilpack.

You will need to make a modification to the daughterboard in the MSPNP to enable variable TPS. This is documented here: http://www.megasquirtpnp.com/models/...m#Section_Five

This of course assumes that you're keeping the 1.8 TPS, which would be a good idea. If you do that, you'll of course need to make a wiring mod to get the new TPS +5Vref and GND, as well as bringing the signal into the MSPNP. Search some of my recent posts, I know I've described within the past month or two which wire is which on the TPS pigtail.

Having swapped the 1.8 TB, you'll need to change the IAC parameters in software, but this is well-documented. Just copy the settings out of DIY's basemap for 94-95.

That's about all I can think of at the moment.


edit: Here's the thread which describes what the various wires coming out of the TPS harness are for.
https://www.miataturbo.net/forum/sho...d.php?t=19008&
The pin numbers I state are relative to a regular MS DB-37 connector, but using these wire colors along with DIY's writeup, you'll figure it out.

mrolo74

Joe I'm still running the 1.6 throttle body right now on the 1.8 motor. Would it make sense once i run the 9093 megasquirt to just keep the 1.6 throttle body. To me it seems easier to get it all to work the way it is but what do i know im the one asking all the questions.

Joe Perez

iTrader: (8)

Oh, sure. If you're still using the 1.6 TB and the 1.6 engine harness, then the MSPNP should in fact truly be plug-n-play. You can stick it in and run it with the default software and no hardware mods whatsoever. It doesn't care how physically large the holes in the middle of the engine are, except in one place: the Req_Fuel constant. And frankly, the difference between a 1.6 and a 1.8 is sufficiently small (12%) that you could even leave that alone and just let the VE table numbers get slightly bigger.

mrolo74

cool thats what i had thoght. also when your talking about the fuel it shouldnt matter that much any how cause ill be running bigger fuel pump and injectors so no matter what i should be safe just running the 9093 with no crazy modifacations.

Joe Perez

iTrader: (8)

Bigger fuel pump not needed. You'll be fine on the stock pump with adequately sized injectors.

mrolo74

cool thanks joe for all the help.