MalibuJack

iTrader: (5)

I was doing some searching for MUT-II and MUT-III status codes and came across this Excel file on Stealth316..

http://www.stealth316.com/misc/3s_mas_liter-per-hz.xls

Its actually almost identical to our cars..

This should be useful information..

MalibuJack

iTrader: (5)

More useful information...

http://mmcdlogger.sourceforge.net/

The diagnostic data applies for the most part to our car.. the diagnostic software and hardware is a crap shoot...

MalibuJack

iTrader: (5)

http://www.stealth316.com/2-fueltrims.htm

More fuel trim info.. Very good read and DOES apply to our car.. (the latter portion of the article)

MalibuJack

iTrader: (5)

http://www.stealth316.com/2-fuelinjection.htm


Additional fuel injection info.. This doesn't 100% apply, but it explains how each input affects the output..

l2r99gst

iTrader: (2)

Malibu,

Wow, I have used that site years ago. It always had great data.

Anyway, I know the Evo Maf is quite a bit bigger than the DSM 2G maf, so I'm not sure if the data will correlate, but I did a quick check to see if it makes any sense.

Using his spreadsheet to find Liters/s of air per Hz, I used the 1521.5 Hz column and corresponding Liters of 179.9935:

pv=nrt

n=pv/rt

R=.082057 l-atm mol-1 K-1


Assuming T of 85F and sea level baro of 14.7 psi (1 atm) and Hz of 1521

n=(1 atm)(179.9935 L/s)/(.082057)(302.6K)

n=7.249 mol/s

1 mol air = 28.84g

n= 7.249 mol/s (28.84 g/mol)= 209.06 g/s or 27.63 lb/min


So, that actually does match up somewhat OK, assuming that 1lb/min is approximately 10 HP. That would make the 1521 HZ = to about 270 HP.

But, I'm almost positive that the ECU already does all of these calculations for us and we can log the mass airflow directly from the ECU without having to worry about any calculations.

Data like this would be good to try to calibrate a GM MAF, for example. I had a GM Maf on my DSM and DSMLink made it extremely easy to calibrate with all of the logging and VE tables, etc, but there is a lot of good data like this on the DSMLink boards, too.


Eric



EDIT: Yes, I just looked this up on the DSMLink boards, and yes, the ECU already calculates the mass airlfow as an OBD-II requirement. So, EvoScan or any other logged should be able to log this. That is what I need to figrue out a concrete load formula.

jcsbanks

My Proscan logger used to display it in g/s or lb/min. Just it was so damn slow it would only read a few times in each gear!

MalibuJack

iTrader: (5)

Yeah the data should be there, just dont remember which item it is..

However that is exactly what I used the data I have here for.. Which was originally to calibrate a few different Ford Cobra sensors..

MalibuJack

iTrader: (5)

FWIW all of the larger MAF's seem to calculate the same output, I think the main difference is the maximum output they can handle.. In other words, a Evo one might hit 2200hz without disruption and restriction, where an earlier one may not.. I think that is where the difference lies.. My experience is otherwise they read similarly..

jcsbanks

2003 Mitsubishi Lancer Evo8 US v0.1.xml has some interesting datalogging items, with item numbers but no requestIDs yet. Some conflict with the original set in Evoscan, so I wondered if they use a different protocol - ie more generic OBD-II stuff?

Although slow updating, I saw 38 lb/min airflow from my Proscan logger near to the top of a gear, so this is rather beyond 1600 Hz. There may be 2 byte items to read for more accuracy as well? If we could read all the OBD-II stuff at higher rates...

Jorge T

iTrader: (18)

fwiw I have a autoenginuity obd2 scanner and it displays "calculated load"so either Mitsu ECU spits it out or it is calculated somehow, but it is there to access. How accurate it is idk.

Even though the maker of this scanner says obd2 works at 50hz, I can only get 6-10 samples per sec logging 1 channel and 1/2 of that if I log 2, 1/3 if that if I log 3 and so on pretty useless IMHO.

RazorLab

iTrader: (8)

pocketlogger also shows calculated load

MalibuJack

iTrader: (5)

Its certainly there.. just have to figure out how to translate the OBD Pid to the right request code..

MalibuJack

iTrader: (5)

http://www.mitsubishi-motors.com/cor...f/2004/16E.pdf

This is a really interesting document that you guys should check out..