Mazda MX-5 NB - DET3 FIT with BOOST

[strndy]

Hello,
I'm trying to do 2 things, with my car:

1) Ignition modification
2) MAF to MAP Conversion

Unfortunately I'm having issues and need help

Ignition
I wanted to control ignition module, but according to MX-5 diagram, there are 2 coils and both controlled by ECU (in your manual, you write that I could destroy your unit, and control only one coil) -- correct me please if I'm wrong.

MX-5 NB Diagrams (page 8-10)
Settings: Retard / Advance 60-2 and Hall effect

So I wanted to modify output from Hall sensor (with pull-up resistor). But when I cut hall's wire and connect Ignition In and Ignition Out, engine won't start .
I even tried to connect it back(car started) and than connected only Ignition In to get at least RPM to piggiback, it still won't start Scope tool shows nothing during start attempt. I don't have oscilloscope, so I can't measure what's actually going on.

MAF to MAP Conversion
I have cut MAF signal cable, connected according to your schema, but car barely starts. Piggyback input/output show 5V (max output) and it results in incredible rich mixture. When I disconnected mazda ECU, output from MAF shows actually 7V, but when connected back to ECU, there is only 1.25V when engine is not working(that's correct).

Looks like I have conencted something fundamentally wrong.
Thx for any help

[gregpe]

dont think is 60-2 in your mazda
check with scope............

[strndy]

That's the issue, scope tool does not show anything

[gregpe]

That's the issue, scope tool does not show anything

check with hall effect setup and i believe is 4 tooth..

[strndy]

Yes, some people says 4, lets try it.

[strndy]

OK, I'm able to read RPM, but when I let flow signal through DET3, I'm not able to start. I even connected DET directli on battery (with fuse), but no luck

Settings:
Retard / advance multitooth signal
Hall effect or optical

8 signals per 720

Tried with and without pullup resistor, no change.

Scope shows nothing

[ktsirigotakis]

Hi my friend here is the way that you have to wire your det3 with mx-5 if you have next gen find the pins on your ecu and wire them also you will find trigger setup. i have done the same on a 323 turbo bpt engine and still work perfect. you can only retard the ignition timing on this type of trigger.

[strndy]

Thx man, I'll try it.
I don't have turbo (yet) so I want to advance ignition on 98 fuel, maybe event e85, so I have basically two options:

1) controll coils directly (where to wire second coin?)

2) Move HALL sensor few degrees in advance and do corrections.


Anyone sucessffuly converted MAF to MAP ?

[Jadzwin]

For this engine it is the best to run it in FIT mode.

You can alter ignition by controlling to ignition modules. One ignition module you connect to ignition input (signal from ecu) and ignition otuput (to coil).
The second one to freq. in (signal from ecu) and freq. out (signal to coil).

In FIT mode you can advance ignition by altering MAF signal (or modifying MAF/MAP conversion map). The lower voltage the more advanced ignition.

The injectors are conrolled then by DET3 so it is easy to tune fuel when you install turbocharger .

[strndy]

In FIT mode you can advance ignition by altering MAF signal (or modifying MAF/MAP conversion map). The lower voltage the more advanced ignition..

I guess this will be black magic, but with forced induction, I will probably not need advancing.

Thank you, this was very useful!

[wolfblind]

For this engine it is the best to run it in FIT mode.

You can alter ignition by controlling to ignition modules. One ignition module you connect to ignition input (signal from ecu) and ignition otuput (to coil).
The second one to freq. in (signal from ecu) and freq. out (signal to coil).

In FIT mode you can advance ignition by altering MAF signal (or modifying MAF/MAP conversion map). The lower voltage the more advanced ignition.

The injectors are conrolled then by DET3 so it is easy to tune fuel when you install turbocharger .

Hi, I have also 1999 Mazda MX5 1.8 NB with supercharger and DET3 with MAP sensor, I tried to run it in piggybackmode so with std. sequential injection, but it runs like a pig. I used this schematic:
and this is the pinout for 1.8NB:

Ignition wiring[Wasted spark with two modules]: module 1: ignition input(signal from ecu) and ignition putput(to coil) with pullup, module 2: freq. in(signal from ecu) and freq. out(to coil) also withpullup. Igniton mode: Retard/advance multitooth signal , Hall effect or ptical, 8 signals per 720 How should I use the second coil with freq. in and output(software setup because the signal doesnt come from the crank sensor like module 1)? Integrated MAP sensor use just in FIT mode? We dont use the Camsahft sensor, correct?

Any help would be appriciated for the piggyback mode to get the MX5 proper run or the FIT mode if it works better[wiring and setup]? I'm also afraid of the lean tip(lean put if I step on the gas), thats way maybe would be better the FIT mode only in batch though.

Anybody succesfull with DET3 in MX5 NB(piggy or in fit mode)?

[strndy]

Hi, I've found out that messing up with MAF signal on MX-5 is not best approach. I was not able to map it properly, especially with large injectors. Throttle response was pretty bad and AFR was never right.

I've switched FIT mode, I firing all 4 injectors at the same time and modifying coils signal. I also made autotunning software in .NET which reads logs corrects fuel map if you are interested.

[strndy]

You can find my settings here:
https://github.com/strndy/DET3-FIT-settings

And analyzer here:
https://github.com/strndy/DET3-FIT-analyzer

[wolfblind]

Hi, I've found out that messing up with MAF signal on MX-5 is not best approach. I was not able to map it properly, especially with large injectors. Throttle response was pretty bad and AFR was never right.

I've switched FIT mode, I firing all 4 injectors at the same time and modifying coils signal. I also made autotunning software in .NET which reads logs corrects fuel map if you are interested.

Hey, yeah with MAF signal definitely not, I've also learnt it. Thanks for the infos, so u didnt try the piggy mode then, as I see or didnt work out well. The autotuning software I have interest of course, where can I download it?

Which .pbp file could u reccomend from the list, u have many , which one is ok?

I see in your setup for Ignition, u use "Retard two ignition module signals" - 2nd ignition signal then on freq. input/output - does it better then the Advanced Multitooth (4 or more teeth - originally NB has 4 tooth triggerwheel)?

Whats your wiring then for FIT mode? Especially for the Ignition then, injectors, etc?


Do you use MAP sensor also for FIT? Did you eliminate the MAF or not?

Low or High Impedance Injectors, I see u have 440cc/min?

Thanks in advance.

[strndy]

Yes I have RX-8 yellow injectors (some say 420, some 440cc), mine showed on flow bench circa 430.

Latest best settings is this one: https://github.com/strndy/DET3-FIT-sett ... olated.pbp
Ignore FUEL MAP, VE TABLE is all the magic you will tune. Also my timing is for shell V-POWER Nitro 100 octane, so be more conservative (more retard).

For the wiring: I fire all injectors together 4x times per 720. I was not able to have smooth idle otherwise. Pay attention to injector opening time, otherwise you idle will never be smooth.

And use wideband lambda, or you will kill engine for sure. I have http://www.innovatemotorsports.com/, AEM will work too. I've tried narrowband (standard) and gave up, it too risky and unproductive.

Wiring for my FIT mode from my head:
I left MAF and Crank sensor untouched, stock ecu does not complain.I originally wanted to remove MAF, but it works perfectly, si I left it untouched.

Injectors
Power ground (#19) to some good engine ground.
All Injectors to Power Out #1 (#20)

Power Out #2 for boost control (turbo)

Analog inputs
All Analog inputs from manual for FIT mode, you can't change the order.

Ignition
Ignition coil #1 signal interrupted to Ignition In / Out
Ignition coil #2 signal interrupted to Frequency In / Out
Both probably with pull up, I don't remember, check manual.

Map Switch
Digital output from lambda controller.

About that autotuning soft.... there is no user interface. But If you will run same settings like me, I can make it work for you. But first you would have to send me your settings and some longs from running. For start u can use magic button "aiE", for basic tunning.

[wolfblind]

Hi, I was away a bit, so I'll fit also some RX8 injectors or Supra, depends on my target HP. Got also WBO2 of course, I know unfortunetaly DET3 has no ability for sequential injection in FIT mode, only batch fire as u also mentioned.

So the crank sensor u let untouched becuase in the FIT manual on pic what I linked above, crank sensor signal goes ignition in?? Or u use just Bipolar Ign out and Bipolar Ign Out Inv. for the crank sensor?? - if yes which cable goes where I mean from MX5 ECU to number 3-4 on this wiring pic?


MAP Switch - dont u use the MAF sensor signal here as input? U said digital output from lambda controller just for autotune or why is that signal instead of MAF?

Thanks...quite clsoe now run the MX5 ....

BTW - in fit mode everything is fine now with your MX5, I mean run properly as it should?

[strndy]

Hi, yeah, car run whole season like a charm with around 170HP (small turbo) and plenty of torque. When I was not pushing hard I had even reasonable mileage. Under 10l/100km.

I just left MAF as it is, fortunately mazda ECU does no go crazy when you put there crazy amount of air, I think it event retards when on boost

DET3 in FIT supports simple AFR correction based on lambda signal and only on MAP Switch input (it's just another analog input).

As I said, I interrupted both COIL signals, left CRANK sensor untouched. You have to find schema, I interrupted engine wiring, not ECU connector.

[wolfblind]

DIdint know the DET3 has AFR correction based on WBO2 signal. Ok if you use MAP Switch for WBO2 correction, then what input is for MAF signal input[MAF Output - Analog Out as in the FIT description] - or u dont use it? Or just using the MAP Sensor signal then instead of MAF?

U said CRANK sensor left untouched, but how do the DET3 knows then , what the actual crankshaft postion is

For wiring the: Power ground (#19) to some good engine ground.
All Injectors to Power Out #1 (#20)
Ignition coil #1 signal interrupted to Ignition In / Out
Ignition coil #2 signal interrupted to Frequency In / Out
Map Switch - Digital output from lambda controller
TPS - Analog In#1
IAT - Analog In#4(using the factory IAT sensor 2B pinout)
CLT - Analog In#3
MAF Sensor Output - Analog Out
MAF Sensor Input - ??
Crank Sensor - ??

Could u check the MAF and Crank on your wiring?

For 170HP u can even use the std. pink NBFL injectors then , like in the factory Mazdaspeed MX5 turbo with 178HP. I'm curious about the fuel consumption with supercharger with batch fire mode on normal driving ....

[strndy]

Hi,
I just ignored MAF and crank sensor, there is not enough inputs for them anyway. Onboard MAP is on Analog #2 i think. Mx-5 is wasted spark (2 times per 720).

In batch mode you don't care about crank/cam position and it takes RPM from coil signal (Ignition In).
It does not really matter, it injects all the time. Nissan was doing it till year 2000 without any issues. Sequential injection is better only for light load, otherwise it does not matter.

I had double the stock torque, so it pink injectors would not handle it well

[SpoolWithMe]

strndy are you saying that you did not connect the Maf and cranks sensor wires to the DET3?