I'm new to the ECU scene so please forgive the noob questions.

MS3-Enhanced from Rev is being built currently. Going into a 2004 MSM. Stock turbo, Flyin Miata full intake kit, Flyin Miata downpipe/full exhaust, larger intercooler. I have new Five-O 650cc EV14 injectors waiting to go in with the ECU.

Do I need a wideband sensor with the new ECU? Where does it go (I thought I read pre-cat in the downpipe)?

I bought an AEM AFR/Boost Failsafe gauge to install with the new ECU. It has the UEGO wideband sensor. Can I use that sensor for the ECU? Or is that sensor there just for the gauge and that's it? If so, what wideband sensor should I get?

 

And, do I need to buy a MAP sensor to replace the MAF that is stock in the car?

Looks like a MAP sensor just runs off of the same vac/boost port that the boost gauge runs off of.... is that true?

 

You don't strictly speaking need a wideband O2 sensor, but you really do want one, as properly tuning an engine without a wideband is very difficult. It goes on the downpipe between turbo and cat. Just take out the stock (narrowband) sensor and put the wideband in its place.

Yes, unless their specs are complete lies it should work fine.

Most people Megasquirting their Miatas replace the stock MAF/AFM setup with MAP+IAT sensors to run speed-density. While not strictly needed, it usually performs better.

In your case, on the already turbocharged Mazdaspeed Miata, you have a MAP sensor which should do just fine unless you go with lots more boost (which you are not if you run the stock turbo). Also, that AEM "failsafe" gauge, which measures the same thing, seems to have an analog output signal for the boost pressure signal. Probably the very same signal as a MAP sensor would give you, but unless the stock MAP is broken I would probably prefer that since it's simpler.

The MAP sensor is connected to intake manifold, just as the boost gauge. They both measure the exact same thing.

(Note: I own neither MSM nor AEM UEGO gauge thingy, this is just based on common sense and basic use of search engines)

 

Thanks for the knowledge. I do appreciate it. Never done forced induction before so I had some gaps (like I know I need a wideband O2, but didn't know the stock one was referred to as a narrowband).

I think I know where the MAP sensor is on the MSM, but I'll google around just to double check. The other port on my intake manifold connects to my blowoff valve (which I learned recently was different than a wastegate, lol). I do know that I already have an IAT sensor that is stock, and was functionally preserved right after the air filter in my aftermarket intake.

 

The stock/standard/common O2 sensor isn't very commonly called "narrowband", other than to distinguish it from a wideband by being sort of opposite.

The blow-off valve is easily distinguishable from a MAP sensor. The BOV has nothing but hose connections or ports (big lines/holes for manifold air inlet + outlet, smaller line for controlling it). The MAP sensor will have an electric cable going from it, just like the IAT.

 

Yes, a new wideband is recommended with your new ECU. How the wideband talks with the ECU is a different story since it has those features

Unit should have a MAP sensor built into the stand alone unit, and you'll just tune off of that. Basically connect it to the intake manifold and have the shortest distance possible from the stand alone baro to the intake manifold.

A BOV unit will not matter too much when tuning with a stand alone unit as it will make the adjustments or you'll tune the adjustments out later on. Though having a recirc valve is optimal for performance. IE: look for how a EFR turbo automatically bursts the BOV charge directly back into the blades

Hope this helps.

 

I meant as far as intake manifold ports, one is connected to my BOV (which is a Turbosmart setup for recirc) and the other is connected to some electrical sensor which I would assume is the MAP.

Now that you mention the port on the MS3E, I just realized that of course that would be the internal MAP in the unit with no need for an additional stock MAP.

See? The random thoughts are starting to link together already

I did some searching and reading that the MS3's can recently be enabled to allow the digital input from the AEM UEGO/Innovate gauge/sensor. Hopefully I can get that to happen.