That thread on the MAP sensor is very interesting. Unfortunately for me I have very little (i.e no) experience on the ASM of an ECCS ECU. So for that reason I am going to do the conversion with a Microchip PIC which I have lots of experience with!
Ed
Nistune Results
Moderator: Matt
-
GZ@hybridka
- Posts: 112
- Joined: Wed May 03, 2006 5:51 pm
- Location: Id, USA
Just out of curiosity , which ecu do you run ? 16 bit sr20 type?
An external micro could do it, you would just be emulating MAF voltage instead of Q itself.
You will need to use MAP (2 for baro correction), RPM, IAT, and maybe even TPS in your algorithm.
You can tap into the 1 degree (or 2 degree depending on whether your referencing cam or crank) signal , the one on the outside edge, to provide a good frequency signal to your MCU.
Using this high-res count will allow you to have faster RPM calculation update speeds in your controller/pc software.
An external micro could do it, you would just be emulating MAF voltage instead of Q itself.
You will need to use MAP (2 for baro correction), RPM, IAT, and maybe even TPS in your algorithm.
You can tap into the 1 degree (or 2 degree depending on whether your referencing cam or crank) signal , the one on the outside edge, to provide a good frequency signal to your MCU.
Using this high-res count will allow you to have faster RPM calculation update speeds in your controller/pc software.
Its an 8 bit CPU.
I will use one Map sensor. baro correction will be performed on power up. My plan is simply just to emulate the MAF voltage. I now have a maf voltage VS RPM VS boost graph I created today, so its just a case of emulating that. I cant see that I would need TPS feedback. But yes IAT will be needed.
Ed
I will use one Map sensor. baro correction will be performed on power up. My plan is simply just to emulate the MAF voltage. I now have a maf voltage VS RPM VS boost graph I created today, so its just a case of emulating that. I cant see that I would need TPS feedback. But yes IAT will be needed.
Ed
-
GZ@hybridka
- Posts: 112
- Joined: Wed May 03, 2006 5:51 pm
- Location: Id, USA
The reason I mentioned TPS is that you are probably going to want to incorporate some sort of acceleration compensation to your output signal, using this variable. The nissan MAF does a lot of the work when it comes to ECCS acceleration compensation, it has very quick update.
A map sensor will take much longer to respond to changes such as acceleration. Short of writing a dedicated fuel acceleration routine within the ecu itself, your going to have to compensate for this with your device.
I have never seen the fuel control of the 16 bit sr/ka ecu documented, perhaps like the ka24e it uses TPS for alphaN functions. If you could decipher the original control you may already have the features you need.
A map sensor will take much longer to respond to changes such as acceleration. Short of writing a dedicated fuel acceleration routine within the ecu itself, your going to have to compensate for this with your device.
I have never seen the fuel control of the 16 bit sr/ka ecu documented, perhaps like the ka24e it uses TPS for alphaN functions. If you could decipher the original control you may already have the features you need.
Ok well I got the SR20 running upto 2 bar boost. We were taking it to be dynoed again today to see how much we were running. But before we got there doing some final tests the gearbox ate itself haha!!!
Its seems its totally stripped all of the teeth of third gear, so that will be repaired and the car sold on. The 2 bar 400bhp+ target has been well exceeded and now its owner wants to try something else. Shame really but it would cost so much to make a gearbox strong enough its just not worth it.
Ed
Its seems its totally stripped all of the teeth of third gear, so that will be repaired and the car sold on. The 2 bar 400bhp+ target has been well exceeded and now its owner wants to try something else. Shame really but it would cost so much to make a gearbox strong enough its just not worth it.
Ed
-
RB30-POWER
- Posts: 62
- Joined: Fri Jul 20, 2007 4:43 pm