Awesome!!!

Are you using the stock temp sensors? If so what was involved in getting them to work nicely?

 

Yes, I am using the stock temperature sensors. The air temperature seems to be very accurate, the coolant temperature is a bit off (maybe 5-8C) but I'm not too worried. I order to get them to work, I measured the voltage and resistance as mentioned here:

http://www.megamanual.com/v22manual/sharesen.htm

 

hno: Ahhhh! I thought I figured it out. I was gonna share all the sensors with the stock ECU and the only mods I´l do with the V3-board is the simple mods with the 1k 1/4w Resistor and the two 470 ohm 1/4w Resistors. Then I would let MS take control over the stock injectors and TAADAA!! I´l have a fuel only MS.
But now this!
Ok, I have looked at it but I don´t really understand what I´m supose to do once I figured out the stock bias resistor. I understand that I should remove the 2.49k bias resistors on the MegaSquirt, R4 & R7. But what am I supose to do next?

/Fredrik

 

After removing R4 and R7, just use the values I posted above in Easytherm, like this:



Then use the Easytherm instructions to download the new sensor data to Megasquirt. That's about it.

You still need to get a CAS from a NA Miata, the stock ones cannot be used.

 

Thanks!
Now things are starting to get clearer.
Since I have a NA 1.8 -95 there is no problem using the stock CAS, but can I use your NB bias resistor values for my 1.8?

How did you get the resistance-values under "Enter Temp-Resistance Pairs"?

/Fredrik

 

It is safe to assume that no, the 94-97 ECU has different bias resistors for both the air and the coolant temp sensor.

I got one value from measuring the resistance of the sensor and at the same time watching the air/coolant temperature from the OBD-II port. The other values were taken from the Resistance/Temperature plots that are in the Mazda service manual for my '02.

 

Did you replace the resistors with jumpers?

 

No, I just left them out. That's what the manual says.

 

Some pics to wet your appetite:

 

 

Tuning on the road has begun. This is so much fun - I wonder how people can bare paying money so they can miss all this fun!

 

You know, I've been playing with the idea of a similar touchscreen laptop run setup and I keep running into the same problem: Vibration. At work I am constantly on my laptop and driving and have destroyed 2 harddrives in 2 years. The techs all say the same thing, that the vibrations of my truck bouncing down a dirt road coupled with the hd spinning at 7200rpm, things get scratched and bent. Are you using some sort of flashdrive void of these problems or are you just banking on never hitting a big pothole/small animal/curb/Hummer with your car.

Also I see you ejected the radio. I am planning to run a Sirius radio through the laptop, through a amp, and into the speakers, allowing me to still control everything from the screen. What type of setup are you planning or do you enjoy listening to youself think more then the added weight of music.

 

The whole carputer thingy started because I have a thing for music and I just couldn't stand swapping CDs in and out. I'm using a laptop as the main unit, so the hard drive spins at 4200rpm and is vibration-resistand, contrary to desktop hard drives. Greece is infamous for having roads that resemble a bombarded scenery (ie uneven tar patches, holes, sewer drains, etc) which means that I bump over a major one at least once every 5 seconds in the 15 miles I drive every day. So far, so good.

As far as radio is concerned, I can't really find a station that will match my taste/mood for any given moment, thus the 3,000 track MP3 library in the car.

 

Got the stock CLT and MAT sensors to work perfectly, ie copycat of the temperatures reported by the stock ECU using OBD-II. So no need to get extra sensors for your 2001-2005, these are really REALLY accurate. Attached are my thermfactor.inc, airdenfactor.inc, matfactor.inc. You will need to download the source code of the MSNSE firmware, drop these files in (replacing the stock GM files), recompile the code and flash the MS with the new firmware.

 

Vibration Fix, get a solid state disk drive, 8 gigs are enough to install XP Pro with room for some MP3s. Roughly $300 and fits in a laptop HDD bay. The 16GB version is $500. They're only getting cheaper. Here's a link, can't make it work with edit http://froogle.google.com/froogle?q=...en&btnG=Search

Nice work Reverant, can't wait to get mine.

 

Right. In about 8 to 10 work hours, I got the whole thing sorted out. Runs like stock in lower/mid rpm and light loads, screams at high rpms, very responsive when opening the throttle (using MAPdot as the AE algorithm, TPSdot won't work properly throughout the entire RPM range). The only thing left is to fine tune the idle AFR once I am 101% happy with the entire VE table.

All in all, I am 111% satisfied with selecting MS as my engine management system!

 

When you have settled down a bit from the initial exhitement , could you check if the fuel milage have changed (I'm trying to find a valid economical reason before taking the plunge)?
I'm hoping that the cruice will be a bit leaner after tuning and even the slightest reduction in fuel consumption could be used to make the case (even if it takes a million miles before brake even)

 

Nice work! How'd you come up with your timing map and have you played with it much?

 

@niklas: Normally, 20 euros would yield about 130-140km. In the days where I was tuning that number has been 170km, twice. I have overrun activated so when I get my foot off the gas completely and coasting down, the injectors are off. We will see what happens within the next few weeks.

@saboteur: Sorry, forgot to mention. Fuel only for now, I'll be dealing with ignition next week. Just wanted to make sure that my injection is perfect before I add another X factor in the whole equation.

Jim

 

Hey Jim,

Any news on getting ignition going?

Cheers