What to & How to Log....

[always_broken]

I've got a palm m130 for my 2g, using Palmnstein logging software.

Currently I'm monitoring RPM/Coolant temp/Air temp/O2/and Timing...

Are these the main things I'm supposed to be logging? Is there a site that teaches you how to log and when to make adjustments? I also have a safc2 to tune with but I'm stil on stock injectors and maf. I'm searching through old threads as this is being typed up.

 

[sd_ff22]

Kenamond posted a very good link and how to once. I'll find it for you.
But the main things you want to log having a 2G are RPM, timing, airflow and O2 bank 1. you can do several runs recording your coolant temp and TPS, but once you learn how they behave you don't need to log them all the time as they take up valuable samples per second space.

So set up to watch RPM, timing, airflow and O2 bank 1, make sure you start logging when pulled over or with a friend logging for you for safety sake, and do a pull from 2500 to 7000 in third gear. once you have those values you can base your adjustments off them. Do several runs and see how your car behaves before you start making changes with the SAFC.

As always, Good luck!

-Dan

 

[sd_ff22]

http://www.dsmtuners.com/forums/newbie-forum/230375-list-loggers-info-tech-article.html

A whold bunch of info on logger programs and tools: just in case.

http://www.dsmtuners.com/forums/tun...276711-first-pocketlogger-datalog-advice.html

this is a good one with a lot of useful info.

-Dan

 

[always_broken]

Hey thanks a lot, I'll be reading those links in a bit.

 

[kenamond]

You can also take a look at the following thread:

http://www.dsmtuners.com/forums/tun...239-how-ecu-determines-air-mass-flowrate.html

As was mentioned, log a 3rd gear pull from 2k-7k rpm (redline in 3rd gear is 95mph in my car, so beware). Log rpm, timing advance, front O2 voltage, and airflow. Before you do this, I'd do some hard driving and monitor (not log) coolant temp, TPS, and intake air temperatures.

The TPS value - if not near 100% at full throttle - may put you into closed-loop mode (O2 sensor used to lean/richen fuel) and would indicate that your throttle cable is not properly adjusted. If TPS is in the high-90% range, you'll be in open-loop mode so that the ECU is just taking rpm and airflow to compute fuel...which is what most folks are worried about.

If coolant temps are too high (above 206°F on a 2g) or too low (I forget the number), then the ECU pulls (retards) timing.

If intake air temps (IATs) are too high or too low, the ECU pulls timing. This is usually due to hot ambient temps (hot day in southern Arizona) or an aftermarket air filter which is pulling hot engine bay air into the motor (cold air intake would help this out).

So once you know where you are with the basic stuff (IAT, TPS, coolant temp), then you can do 3rd gear pulls and make better sense of the log.

The link above has a post from zippyshoe of a PDF document that describes this a bit more. He also posts the 2g timing and fuel maps (maybe 1g, too - I forget). To make use of these, you have to convert airflow from lb/min to load in g/rev. To do this, use the following equation:

GREV=LBMIN*454/RPM

This is the mass of air in each cylinder at that point in the log (at the corresponding rpm).

The g/rev number (called "load") and engine rpm are used by the ECU to look onto the map (table) and find out what timing advance should be used as well as what air:fuel ratio (AFR) to use. The timing advance is what you can log directly. If you go through each (rpm,load,timing) multiplet from your log, you can look at the (rpm,load) value on the timing map and see if your timing advance is the same as (or close to) the map value. Knowing your coolant temp and IAT status, you should be able to tell if your timing is "close enough" to the map value. If you get motivated, you can plot the map timing and logged timing together versus rpm and see if they track each other. If your logged timing dips below the map values, you're knocking at that rpm.

If you have a lamda gauge (wideband O2 sensor + gauge), you can do the same thing with the fuel map, but you replace timing advance with AFR. But many folks tune to no-knock leaning out different rpm ranges until knock shows up and then richen it back up a bit.

Hope that gets you started.