tuning 101

[flacopower]

hi. i am new to the dsm tuning world and have some questions. i have tuned in the past using an apexi power fc on my friends rx7. that however tells me straight up the basic information i need( inj duty cycle, knock, air fuel ratios). i purchased a 2g datalogger with obd gauge and i can't decipher any of the info, stft ltft ignition timing and how they relate to knock and my injectors.. any help would be appreciated. oh and i will be tuning using an safc 2.. should i stay with obd gauge or are there other programs that are simpler to decipher?

 

[g63tawd]

There is always the pocketlogger. But the best tuning tool is to have some type of wideband. www.pocketlogger.com tells you just about everything you need to know about whats going on w/ your engine.

 

[playitlouddsm]

If you have the money get dsmlink, www.dsmlink.com that will tell you everything you need.

 

[99gst_racer]

There is always the pocketlogger. But the best tuning tool is to have some type of wideband. www.pocketlogger.com tells you just about everything you need to know about whats going on w/ your engine.

Not true. The pocketlogger is an excellent logging device, but it does not read IDC's and knock counts for 2G's, like what the thread starter is looking for.


flacopower - I have a little bit of experience with the Power FC and the FD's. If you're looking for a similar tuning device for a DSM, then DSMlink is the way to go. It is a logging device and tuner all in one, much like the Power FC. The only difference is that DSMlink will require a laptop.

 

[MrBoxx]

You can use DSMLink with a Palm, if you absolutely HAD to, though. It would be better and easier with a laptop.

Can I use DSMLink with a PDA?

This question is a little tricky. Yes, you can, but only due to the generosity of one of our more active users, Hal Landry. He has devoted a good bit of his personal time to develop a version of the DSMLink client that runs on a Palm device (true Palm, no Visors or anything like that). The requirements include Palm OS 3.5 or later with color being highly recommended. The original software was written using a Palm IIIc, which can be had these days pretty cheaply off E-bay. This question is a little tricky because we don't want to suggest that the Palm is a fully supported platform. It's not.

 

[dthquazi1]

what are the system requirements for dsm link. If they are low you should be able to get a cheap lap top and it will really benefit you.

 

[flacopower]

yeah i know about dsm link.. however i have a 99 gst and so i would need a eprom ecu and i don't really feel like spending more on tuning when i just spent 300 for the datalogger and safc2.. my question is how do i calculate the idc and the knock count? doesn't it have something to do with the stft and the ltft?

 

[dthquazi1]

if you have a datalogger. it will show knock on it. Run a datalog and where you see that your o2 voltage is showing a lean mix at a certain rpm. go to that rpm and add a little fuel. Simple.

 

[flacopower]

well i just did a run and both stft and ltft fluctuated a bit but once i hit WOT then they both were at zero. thats good right? when me and my rx7 tuned we just went by the o2 sensor voltage and tuned down until it read between .9 and .93 at WOT.. does that sound right?

 

[99gst_racer]

if you have a datalogger. it will show knock on it.

Wrong. Stock 2G ECU's do not send information from the knock sensor through the diagnostic port. Like I stated above, Dataloggers do not read knock on 2G's!

yeah i know about dsm link.. however i have a 99 gst and so i would need a eprom ecu and i don't really feel like spending more on tuning when i just spent 300 for the datalogger and safc2.. my question is how do i calculate the idc and the knock count? doesn't it have something to do with the stft and the ltft?

Your logger/AFC combo is a basic set-up. It's good, and proven, but it will not display the information that you're looking for. You can get a pretty good tune by watching your O2 voltage and timing advance. If you really feel the need to view knock and IDC's, then you're better off selling the equipment that you have and putting the money toward an EPROM and DSMlink.

Also, your short term and long term fuel trims have nothing to do with IDC's and/or knock counts.
Read these links:
http://www.dsmtuners.com/forums/showthread.php?t=58403

http://www.dsmtuners.com/forums/showthread.php?t=105569

 

[flacopower]

Also, your short term and long term fuel trims have nothing to do with IDC's and/or knock counts.
Read these links:
http://www.dsmtuners.com/forums/showthread.php?t=58403

http://www.dsmtuners.com/forums/showthread.php?t=105569

yeah i know the fuel trims have nothing to do with knock or idc's, but they do have to do with a/f ratios.. if both stft and ltft are at zero than i am perfect right? not lean and not rich correct?.. on a seperate note, how do you know once your injectors are maxed out? and how would i adjust timing?

 

[blackGSX2g]

if you have a datalogger. it will show knock on it. Run a datalog and where you see that your o2 voltage is showing a lean mix at a certain rpm. go to that rpm and add a little fuel. Simple.

Unless you have a wideband, this doesn't help you a whole lot. Your o2 voltage should cycle rich and lean quite frequently unless you are in open loop, high throttle conditions.

Have your logger output a graph of your timing curve, and where there are dips (knock), adjust fuel at that RPM.

yeah i know the fuel trims have nothing to do with knock or idc's, but they do have to do with a/f ratios.. if both stft and ltft are at zero than i am perfect right? not lean and not rich correct?.. on a seperate note, how do you know once your injectors are maxed out? and how would i adjust timing?

Your fuel trims only have to do with your closed loop A/F ratios. Once you put a fair load on your motor, the o2 and all corresponding trims are ignored. As Paul said, both your STFL and LTFTs will always be at zero when you are in open loop operation. If you are in closed loop, your trims should hang as close to zero as you can get, with a negative % indicating a rich condition and a positive % indicating a lean condition.

With only a datalogger on a 2g, you cannot adjust any timing. You can only tune for a smooth climbing timing curve by getting rid of knock (dips in the curve).

 

[dthquazi1]

Unless you have a wideband, this doesn't help you a whole lot. Your o2 voltage should cycle rich and lean quite frequently unless you are in open loop, high throttle conditions.

Have your logger output a graph of your timing curve, and where there are dips (knock), adjust fuel at that RPM.



Your fuel trims only have to do with your closed loop A/F ratios. Once you put a fair load on your motor, the o2 and all corresponding trims are ignored. As Paul said, both your STFL and LTFTs will always be at zero when you are in open loop operation. If you are in closed loop, your trims should hang as close to zero as you can get, with a negative % indicating a rich condition and a positive % indicating a lean condition.

With only a datalogger on a 2g, you cannot adjust any timing. You can only tune for a smooth climbing timing curve by getting rid of knock (dips in the curve).

I agree with you but for the people that dont i always tell them that they need one but can get away with not having one. When they tune i tell them to tune rich just to be safe because you really are not getting a true value from the o2

 

[dthquazi1]

I agree with you but for the people that dont i always tell them that they need one but can get away with not having one. When they tune i tell them to tune rich just to be safe because you really are not getting a true value from the o2

like i meant anywhere where it knocks add fuel. I didn't say it up there but i meant it. I have been tuning on a car with a wideband so i got my two mixed up.

 

[flacopower]

well if i have to look at the timing curve than obd gauge is out of the question.. do any of the other palm programs allow you to zoom in or isolate just one part? on obd gauge i have three things taking up the little palm screen so it makes it hard to tell at what rpm the timing is dipping.. all i know is that is definetly not a smooth curve at this time

 

[madman]

well if i have to look at the timing curve than obd gauge is out of the question.. do any of the other palm programs allow you to zoom in or isolate just one part? on obd gauge i have three things taking up the little palm screen so it makes it hard to tell at what rpm the timing is dipping.. all i know is that is definetly not a smooth curve at this time

I'm using the similar setup. Pocketlogger with SAFC I, but I don't have the obd gauge. Actually I'm not sure what gauge you are talking about.

When I make a run, I watch the RPM, TIMING, and O2. This all fits on the palm screen.
Sometimes I add AIR FLOW but then is knocks the O2 down one and then you can's see it till after you make you run, save the run, look at it and then scroll down.

It really shouldn't matter what you can see while you are making you'r run anyways. The pocketlooger will save it and you can look up the info afterwards. Then make adjustments, make a run, save and look........over and over till you're happy.

I had a dip in my timing at 4300 rpm. I actuall dropped all my settings (leaned it out) by 1% starting at 4k and fixed my timing curve......so each car may react different....just make adjustments 1% at a time up or down till it starts to smooth out.

I followed the same link as above and it works great.

When you are doing you fuel trims, use the "view" option on the logger/palm
watch- ltft/stft/rpm..adjust using lo throtle on the SAFC and yes trims should = 0 for a 2G

When you are making a run use the hi throtle on the SAFC and go to log/datalog on the logger/palm and watch your RPM/TIMING/O2.......
when your ready to floor it, hit "start" on the logger/palm and then make the run at as soon as you let off the gas when you hit around 7k.....hit "STOP" on the logger/palm.....select save (the icon that looks like a disk) and then view......(magnifing glass)

You want to get the fuel trims good first then go to hi trottle tuning.


I'm tired of people telling us that we should get a DSM Link everytime we ask questions regarding the pocketlogger.

Yes it is probably superior but I, like flacopower have bought this setup and don't have the money and or the need at this time to go to DSM Link...