Fc-datalogit

[paulr33]

as per the instructions when you load datalogit i've emailed my request through the the datalogit guys to join the yahoo groups.

[Bl4cK32]

Had a chance to test mine out today, with the help of Cubes and his laptop.

Had to setup the com port to recognize the usb adaptor supplied by the Datalogit people. After it was done, we had no problems with data transfer, or dropouts.

I need get a AFR meter on the car to fully utilise the software and cable

Also i can recommend people to get Dataloglab. It makes a hell of a difference to reading the logged data that we grabbed while cruising.

Edited November 27, 2005 by Bl4cK32

[Cubes]

Whats the brand is your Serial->USB adaptor Bl4ck32?

EDIT: Girls... Post your datalogit logs.

The highest load (airflow hence power) peak we saw was

Bl4ck32's peaks at 17322, approx load point 17-18 - RB20DET Highflow ~15-16psi)

Mine peaks with a load of 14832, approx load point 16-17 (VG30DET TUrbo ~12psi tailing off to 10psi)

Edited November 27, 2005 by Cubes

[Bl4cK32]

The one supplied by the Datalogit people. It hasnt got the brand on the cable, but the cd with drivers supplied has Digitus printed on it.

[Cubes]

This is the Serial to USB dongle the datalogit likes/uses.

http://www.ferret.com.au/articles/14/0c02f714.asp

I've had a little look around, it looks as if the dongle is only available in NZ.

Edited November 27, 2005 by Cubes

[Cubes]

On the topic of datalogging...

The Map Watch window is awesome for tuning, you can see exactly which load and rpm point has what knock afr etc..

Edited November 27, 2005 by Cubes

[paulr33]

very handy it is. what ive been doing is setup the temp ign increase on the hand controller then load datalogit and run map watch with advanced knock and watch the avg / max values to see how it pans it and you can quickly work out what areas where you can afford more timing

i had a 20 minute datalogit session just lost as the laptop battery went flat and datalogit doesnt write/commit until the end

[Cubes]

Why does the values from basic knock differ from advanced knock?

The basic knock values read higher, i.e one of the logs had a ping of 115 in basic yet it was only 60 in advanced. Both set to max.

Edited December 3, 2008 by Cubes

[paulr33]

not sure on the difference, ive only ever used advanced knock

manual doesnt seem to say much about it either.

[justin911]

me want

[Cubes]

My H/C appears to be the same reading as the basic knock.

[paulr33]

hmm that explains it then cos i was doing advanced knock watch and i saw a few rows of 100+ but the max the hand controller showed was 52. and i dont recall my tune knocking that much also. good thinkin 99. ive asked to join the usergoups so hopefully this stuff is covered in there

[Emre]

Why does the values from basic knock differ from advanced knock?

The basic knock values read higher, i.e one of the logs had a ping of 115 in basic yet it was only 60 in advanced. Both set to max.

<{POST_SNAPBACK}>

It has always behaved that way. I remember asking the question and the answer from the programmers of the Datalogit was :

There should be no difference between Basic and Advanced Knock. The Basic and Advanced groups correspond to 2 different commands to get different groups of data out of the Power-FC.

Since the knock reading has a peak and hold effect between readings, there is a chance that either the Advanced otr the Basic knock will see a higher knock, but shouldn't happen consistently.

There is a chance that there is a bug in FC-Edit or actually in the Power-FC itself. What is your Power-FC type and version number?

There was also another input from a member who contributes regularly.

Unfortunately I do not know the exact reason why Basic knock shows higher values than Advanced knock. Here are some possibilities:

1)      Sampling rates are different

a.      One setup may be checking for knock values at a higher sampling frequency and that’s why it’s able to recorded some higher values

2)      On some applications, there are two knock sensors

a.      While it’s doubtful, that each sensor is tied to a different mode (one for advanced, one for basic) you never know what was going through the engineer’s mind that set up the system.

b.      If both modes sample at the same rate (thus #1 possibility is eliminated), it may be possible that one mode shows the peak value for one of the two sensors while the other mode shows an average value.

Whatever the case, it’s of little value to look at just a peak number from a knock sensor. You really need to look at the datalog in the chart screen and see the plot of knock sensor values. Remember, a knock sensor is nothing more than a specialized microphone that’s designed to listen for sounds in the frequency range of knock. As the engine rpm is increased it’s normal to see higher values from the knock sensor. Actual knock is going to look like a quick spike from the normal values. Thus, it’s going to show up whether you look at it in the Advanced or the Basic mode. 

You ears and a good stethoscope or HKS Knock amplifier with headphones is an even better way to listen for knock.

.

[justin911]

hey with the datalogit, what differant factors does it let you change the timing on ?

I think paul said earlier u can change it based on the water temp, but are there any others ??

[Emre]

It has access to ignition correction values for air temp, water temp, voltage, etc...

Every Power FC has these correction tables, but they are not accessible with the hand controller. On the other hand, i have never touched mine, as they look pretty spot on with default values.

For example (for the GTR Datalogit), upto 50 degrees intake temp, it uses the normal values from the ignition map. From 50 to 60 C, it starts taking out 3 degrees, between 60 and 70 C, it takes another 2 degrees (up to 5 all up) from the ignition map. In short, if your intake temps were 70 C, it would run 5 degrees less ignition.

As i stated long time ago, the main advantage of the Datalogit as its name suggests, is to log data. Unlocked tuning parameters is just an added bonus.

[Cubes]

Emre,

I'll go by the basic knock as that has consistently returned higher knock values with both Bl4ck32 and my R32 AP PowerFC.

With the PFC H/C plugged in at the same time the H/C has reported the same knock value as the datalogits basic knock.

It appears my and bl4ck32's knock sensors are working well.

General driving and cruising it basically sits on 1, give it a boot full and it will creep to 20-30 and that is it, if it goes higher then it will most definitely hit either 60ish or 100ish with quick spikes. It never holds an even 45+.

Edited November 27, 2005 by Cubes

[Emre]

I wanted to check the same thing, but while logging data, my hand controller freezes and doesn't display or hold any values.

On the other hand, while i had some high knock values under 'basic knock', there were no warning flashes coming from the dash.

[Cubes]

Interestering...

When Bl4ck32 was using the laptop it was in advanced knock, i gunned it in third, dash light flashed and asked him if it went over 50 (I changed the max value before dash light flashes), he said no. :S

I've since pulled a few degree's out around 4000rpm, no more dash light flashing as there is no longer any det at that rpm. 5600rpm+ i've pulled a couple degree's out but I won't take the car there as its leaning out from then onwards.

Edited November 27, 2005 by Cubes

[justin911]

the air temp correction would be good but that obviously doesnt work on a r33 gtst ya ?

[Cubes]

Interesting links....

http://www.rx7club.com/showthread.php?t=14...ght=Basic+Knock

http://www.rx7club.com/showthread.php?t=14...ght=Basic+Knock

Take the knock readings with a pinch of salt. Throw it on the dyno watch the exhaust and listen for ping.

Edited November 27, 2005 by Cubes