HEy im just wandering if any one in darwin happens to know how to tune/drive a Apexi SAFC, my car is at revit up performance at the moment and it would make life easier for adam and myself if we could shed some light on it......
Cheers
Chris
Full Version: Tuning Safc
Here goes off memory , hope this helps chris, give me a call if you need anything else.
Basic AFC Tuning
A "How-to" Guide by Cody Graham
Low Throttle Settings
Ok, first we will set the Low Throttle setting on the S-AFC, so don't go above 30% throttle during this time. Set your throttle adjustment points at 1000, 2000, 3000, 4000, 5000, 6000, 7000, and 7500. (There are 12 Points to set for the SAFC-II, so you might want to choose 800, 1600, 2200, 2800, 3400, 4000, 4600, 5200, 5800, 6400, 7000, 7600. We'll continue with the discussion for the SAFC-I for these purposes, but the same principles will apply for the SAFC-II.) To set the 1000 setting, just let the car idle in your driveway. You will need to be watching your logger and your S-AFC at this point. Just to get you used to what you will need to monitor, this is what you're going to need to look at-- First check what your airflow is... If it is under 125 you are in low fuel trim band; 125-175 you are in mid trim band; over 175 and you are in your hi trim. Ok..., the next thing you need to look at is what that fuel trim is at, i.e., if you're at 75 Hz you need to look at the low fuel trim settings. Finally, look at what RPM you are at. All right, now back to the tuning part...
Let the car idle in your driveway. Airflow should be somewhere under 100hz, and RPM should be about 700 or so. So you need to take a look at your Low fuel trim. If your trim is over 100% you need to richen the 1000rpm mark up. So move it up a bit, then once your O2s start cycling again check the trim again. If it's still over, move it up more, and repeat until you get to 100%. Do the opposite if you are under 100%.
Next we will do the 2000rpm mark. Get on a nice long stretch of road, and get the car in 3rd gear or higher (varies based on speed limit etc). Now give the car just enough throttle to where your RPMs aren’t increasing or decreasing. At this point, it helps if you have a friend in the car. Have your friend take a look at your fuel trim (look at whichever one is relevant, based on the chart above). If the trim is over 100%, add fuel; if under 100%, lean it out.
Finally do 3000rpm. Once again, just cruise along without allowing your RPMs to vary too much. Check which fuel trim your ECU is using, then adjust that RPM's set point until that trim level is at 100%.
Now you can go on and do 4000 rpm, 5000, etc. But I just set the rest of them at what the 3000rpm mark is, and call it even. Mainly because it isn't very often that I'm at 4000 rpm and not at full throttle.
Now we get to the fun part - high throttle settings!
High Throttle Settings
This is truly an art. There are many ways to go about doing it, and this is just my way. Take it with a grain of salt, don't follow it to the T, and if anything goes wrong make something else up.
All right. The first thing I do is to set my high settings to the same setting all the way across. Usually, I use whatever the 3000RPM low setting was across the board as a starting point.
All right now. I did this solo, but it would probably be easier with two people. Just have the second person do whatever the first person isn't doing...
OK.
1) Start at 2000rpm in 3rd gear, start recording the data log, then wait maybe half a second and floor it.
2) Hold the gear all the way until you bounce off the rev limiter (or if you don't have a rev limiter hold it to whatever you feel like holding it to).
3) Now pull off the highway and into a parking lot. Review the log. What you want to look for is any dip in timing or flattening of timing or anything of that sort.
4) If there is timing getting pulled or flattening out anywhere you need to richen that section of revs up. Look at the corresponding engine speed then add fuel to that section on the S-AFC. Only increase it by 1 or 2% unless you are seeing a massive dive in timing. In that case richen it up a good 5% or so.
5) If there is no timing getting pulled and you have a nice long steady increase in timing you are running too rich. Lean it out across the board using good judgment. I take steps of 3% when leaning things out.
6) Repeat until subtracting fuel gives you knock (i.e. when timing takes a plunge)
A few things to clear up:
First off..., the reason I suggest that you monitor timing instead of knock count while tuning is because of the way that data loggers work. They poll the ECU for information a given number of times per second. It's usually around 80 times a second, if you are monitoring 10 variables, since each variable is being updated 8 times per second. Knock is an instantaneous thing-- the ECU sees it, and then basically forgets about it. So when your data logger asks for knock, it gets whatever the current knock count is. That means that you will miss a lot of knock counts even if the only variable you are monitoring is knock. Since the ECU adjusts timing based on knock counts, and the ECU never misses a knock count (unless you have a faulty sensor), you can just watch timing instead:
8 counts of knock (or more) and the ECU retards timing
4-7 counts of knock and the ECU levels timing off
1-3 counts of knock and the ECU slowly increases timing
0 counts of knock and your ECU will greatly increase timing
So while tuning, instead of aiming for "no knock", aim for "no retarded timing"!
Hope this helps you out.
Basic AFC Tuning
A "How-to" Guide by Cody Graham
Low Throttle Settings
Ok, first we will set the Low Throttle setting on the S-AFC, so don't go above 30% throttle during this time. Set your throttle adjustment points at 1000, 2000, 3000, 4000, 5000, 6000, 7000, and 7500. (There are 12 Points to set for the SAFC-II, so you might want to choose 800, 1600, 2200, 2800, 3400, 4000, 4600, 5200, 5800, 6400, 7000, 7600. We'll continue with the discussion for the SAFC-I for these purposes, but the same principles will apply for the SAFC-II.) To set the 1000 setting, just let the car idle in your driveway. You will need to be watching your logger and your S-AFC at this point. Just to get you used to what you will need to monitor, this is what you're going to need to look at-- First check what your airflow is... If it is under 125 you are in low fuel trim band; 125-175 you are in mid trim band; over 175 and you are in your hi trim. Ok..., the next thing you need to look at is what that fuel trim is at, i.e., if you're at 75 Hz you need to look at the low fuel trim settings. Finally, look at what RPM you are at. All right, now back to the tuning part...
Let the car idle in your driveway. Airflow should be somewhere under 100hz, and RPM should be about 700 or so. So you need to take a look at your Low fuel trim. If your trim is over 100% you need to richen the 1000rpm mark up. So move it up a bit, then once your O2s start cycling again check the trim again. If it's still over, move it up more, and repeat until you get to 100%. Do the opposite if you are under 100%.
Next we will do the 2000rpm mark. Get on a nice long stretch of road, and get the car in 3rd gear or higher (varies based on speed limit etc). Now give the car just enough throttle to where your RPMs aren’t increasing or decreasing. At this point, it helps if you have a friend in the car. Have your friend take a look at your fuel trim (look at whichever one is relevant, based on the chart above). If the trim is over 100%, add fuel; if under 100%, lean it out.
Finally do 3000rpm. Once again, just cruise along without allowing your RPMs to vary too much. Check which fuel trim your ECU is using, then adjust that RPM's set point until that trim level is at 100%.
Now you can go on and do 4000 rpm, 5000, etc. But I just set the rest of them at what the 3000rpm mark is, and call it even. Mainly because it isn't very often that I'm at 4000 rpm and not at full throttle.
Now we get to the fun part - high throttle settings!
High Throttle Settings
This is truly an art. There are many ways to go about doing it, and this is just my way. Take it with a grain of salt, don't follow it to the T, and if anything goes wrong make something else up.
All right. The first thing I do is to set my high settings to the same setting all the way across. Usually, I use whatever the 3000RPM low setting was across the board as a starting point.
All right now. I did this solo, but it would probably be easier with two people. Just have the second person do whatever the first person isn't doing...
OK.
1) Start at 2000rpm in 3rd gear, start recording the data log, then wait maybe half a second and floor it.
2) Hold the gear all the way until you bounce off the rev limiter (or if you don't have a rev limiter hold it to whatever you feel like holding it to).
3) Now pull off the highway and into a parking lot. Review the log. What you want to look for is any dip in timing or flattening of timing or anything of that sort.
4) If there is timing getting pulled or flattening out anywhere you need to richen that section of revs up. Look at the corresponding engine speed then add fuel to that section on the S-AFC. Only increase it by 1 or 2% unless you are seeing a massive dive in timing. In that case richen it up a good 5% or so.
5) If there is no timing getting pulled and you have a nice long steady increase in timing you are running too rich. Lean it out across the board using good judgment. I take steps of 3% when leaning things out.
6) Repeat until subtracting fuel gives you knock (i.e. when timing takes a plunge)
A few things to clear up:
First off..., the reason I suggest that you monitor timing instead of knock count while tuning is because of the way that data loggers work. They poll the ECU for information a given number of times per second. It's usually around 80 times a second, if you are monitoring 10 variables, since each variable is being updated 8 times per second. Knock is an instantaneous thing-- the ECU sees it, and then basically forgets about it. So when your data logger asks for knock, it gets whatever the current knock count is. That means that you will miss a lot of knock counts even if the only variable you are monitoring is knock. Since the ECU adjusts timing based on knock counts, and the ECU never misses a knock count (unless you have a faulty sensor), you can just watch timing instead:
8 counts of knock (or more) and the ECU retards timing
4-7 counts of knock and the ECU levels timing off
1-3 counts of knock and the ECU slowly increases timing
0 counts of knock and your ECU will greatly increase timing
So while tuning, instead of aiming for "no knock", aim for "no retarded timing"!
Hope this helps you out.
thanks for that man see how i go tomorrow...
Chris
Chris
No problem glad I could help, if you need anything else let me know but that should get you started just remember account for the crap weather and fuel up here and do not lean it out to much. Do not want to go bang.
yeah its been going bang a fair bit, above 4grand it just back fires like crazy, im worried, to be honest.......
does it happen only when it comes on boost, what injectors are you runnning in it, also what fuel pressure regulator do you have, does it surge , hesitate, or just go bang and shoot fuel out of the exhaust.
when on boost, it hesitates a little then back fires, injectors are standard, so is regulator, ive never had problem with fuel, its always running to rich
| QUOTE (KenFastPerformance @ Dec 19 2004, 10:13 PM) |
| Here goes off memory, hope this helps chris, give me a call if you need anything else. Low Throttle Settings Ok, first we will set the Low Throttle setting on the S-AFC, so don't go above 30% throttle during this time. Set your throttle adjustment points at 1000, 2000, 3000, 4000, 5000, 6000, 7000, and 7500. (There are 12 Points to set for the SAFC-II, so you might want to choose 800, 1600, 2200, 2800, 3400, 4000, 4600, 5200, 5800, 6400, 7000, 7600. We'll continue with the discussion for the SAFC-I for these purposes, but the same principles will apply for the SAFC-II.) To set the 1000 setting, just let the car idle in your driveway. You will need to be watching your logger and your S-AFC at this point. Just to get you used to what you will need to monitor, this is what you're going to need to look at-- First check what your airflow is... If it is under 125 you are in low fuel trim band; 125-175 you are in mid trim band; over 175 and you are in your hi trim. Ok..., the next thing you need to look at is what that fuel trim is at, i.e., if you're at 75 Hz you need to look at the low fuel trim settings. Finally, look at what RPM you are at. All right, now back to the tuning part... Let the car idle in your driveway. Airflow should be somewhere under 100hz, and RPM should be about 700 or so. So you need to take a look at your Low fuel trim. If your trim is over 100% you need to richen the 1000rpm mark up. So move it up a bit, then once your O2s start cycling again check the trim again. If it's still over, move it up more, and repeat until you get to 100%. Do the opposite if you are under 100%. Next we will do the 2000rpm mark. Get on a nice long stretch of road, and get the car in 3rd gear or higher (varies based on speed limit etc). Now give the car just enough throttle to where your RPMs aren’t increasing or decreasing. At this point, it helps if you have a friend in the car. Have your friend take a look at your fuel trim (look at whichever one is relevant, based on the chart above). If the trim is over 100%, add fuel; if under 100%, lean it out. Finally do 3000rpm. Once again, just cruise along without allowing your RPMs to vary too much. Check which fuel trim your ECU is using, then adjust that RPM's set point until that trim level is at 100%. Now you can go on and do 4000 rpm, 5000, etc. But I just set the rest of them at what the 3000rpm mark is, and call it even. Mainly because it isn't very often that I'm at 4000 rpm and not at full throttle. Now we get to the fun part - high throttle settings! High Throttle Settings This is truly an art. There are many ways to go about doing it, and this is just my way. Take it with a grain of salt, don't follow it to the T, and if anything goes wrong make something else up. All right. The first thing I do is to set my high settings to the same setting all the way across. Usually, I use whatever the 3000RPM low setting was across the board as a starting point. All right now. I did this solo, but it would probably be easier with two people. Just have the second person do whatever the first person isn't doing... OK. 1) Start at 2000rpm in 3rd gear, start recording the data log, then wait maybe half a second and floor it. 2) Hold the gear all the way until you bounce off the rev limiter (or if you don't have a rev limiter hold it to whatever you feel like holding it to). 3) Now pull off the highway and into a parking lot. Review the log. What you want to look for is any dip in timing or flattening of timing or anything of that sort. 4) If there is timing getting pulled or flattening out anywhere you need to richen that section of revs up. Look at the corresponding engine speed then add fuel to that section on the S-AFC. Only increase it by 1 or 2% unless you are seeing a massive dive in timing. In that case richen it up a good 5% or so. 5) If there is no timing getting pulled and you have a nice long steady increase in timing you are running too rich. Lean it out across the board using good judgment. I take steps of 3% when leaning things out. 6) Repeat until subtracting fuel gives you knock (i.e. when timing takes a plunge) A few things to clear up: First off..., the reason I suggest that you monitor timing instead of knock count while tuning is because of the way that data loggers work. They poll the ECU for information a given number of times per second. It's usually around 80 times a second, if you are monitoring 10 variables, since each variable is being updated 8 times per second. Knock is an instantaneous thing-- the ECU sees it, and then basically forgets about it. So when your data logger asks for knock, it gets whatever the current knock count is. That means that you will miss a lot of knock counts even if the only variable you are monitoring is knock. Since the ECU adjusts timing based on knock counts, and the ECU never misses a knock count (unless you have a faulty sensor), you can just watch timing instead: 8 counts of knock (or more) and the ECU retards timing 4-7 counts of knock and the ECU levels timing off 1-3 counts of knock and the ECU slowly increases timing 0 counts of knock and your ECU will greatly increase timing So while tuning, instead of aiming for "no knock", aim for "no retarded timing"! Jope this helps you out. |
plagiarism
n 1: a piece of writing that has been copied from someone else and is presented as being your own work 2: the act of plagiarising; taking someone's words or ideas as if they were your own [syn: plagiarization, plagiarisation, piracy]
Source: WordNet ® 2.0, © 2003 Princeton University
---------
I felt it nessesary to point this out.
All this information was originally raised from the U.S via a DSM forum and has been colated by Cody Graham and is available _Right Here_ for all to see.
So some kudos should be given to the relevant people for their hard work.
That is all, thank you.
I´ll be here all week, try the veal.
How long has it ben doing this and have you changed anything that effected or caused this to happen, does it happen all the time or just on occasion.
| QUOTE (freddynolegs @ Dec 19 2004, 10:46 PM) |
| when on boost, it hesitates a little then back fires, injectors are standard, so is regulator, ive never had problem with fuel, its always running to rich |
Do you have access to a wideband O2 sensor at all?
If not i´d greatly recommend getting one.
Even an exhaust gas temperature guage would be of more use than just going off the timing values as was suggested earlier in this thread on how to tune an SAFC.
Check your ignition system aswell.
If it´s not upto par, or the timing is too far retarded (from stock values) then it will do exactly that.
Hesitate then backfire.
yeah the thing i changed was kinda big actually, I put a t28 on it, ever since the nbeen running like a bag of shit
So now I need to put where I got my information from on everything I put on here sorry Brenton ( <- wrong name) just trying to help someone out. Can't remember exactly what to do wit out sitting in front off one again. Had the information from one I tunned before thought it was relevant.
should a bigger turbo make that much difference to the way the car responds, as soon as the turbo was installed the timing was off, no response nothing, barley started the first time i kicked it over....... 
| QUOTE (KenFastPerformance @ Dec 19 2004, 10:54 PM) |
| So now I need to put where I got my information from on everything I put on here sorry Brenton just trying to help someone out. Can't remember exactly what to do wit out sitting in front off one again. Had the information from one I tunned before thought it was relevant. |
My names Nathan not Brenton......
Sorry I should have introduced myself first.
Call me a pedantic twit if you´d like but I feel that people should get recognition for their work instead of people saying it´s off this own memory.
You being a mechanical engineer should have got that drilled into your head at uni.
| QUOTE (freddynolegs @ Dec 19 2004, 10:56 PM) |
| should a bigger turbo make that much difference to the way the car responds, as soon as the turbo was installed the timing was off, no response nothing, barley started the first time i kicked it over....... |
Are you sure it´s spot on now?
This is where a EGT sensor would REALLY help.
Sounds too me like the timing is still too far retarded. Check that out first.
What setting do you currently have in the SAFC?
regardless of where he got the info from im thankful for the info, not many people seem to want to help........
The timing should not have changed from just changed a turbo mmm, how far out was the timing when you kicked it over. and what is the timing running at now. Is low response good.
The timing was like another set of markers out when i first checked it, took it to adam and he set it 5deg btdc or whatever is stock for sr20's, there is alot of play in the timing at the moment and im not sure whether thats the way it should be.......
Sorry whitefc,
Did not mean to have a go at you just did not copy whole document just relevant parts so did not have authors name on there sorry about that. Have now corrected the post.
Did not mean to have a go at you just did not copy whole document just relevant parts so did not have authors name on there sorry about that. Have now corrected the post.
| QUOTE (freddynolegs @ Dec 19 2004, 11:03 PM) |
| The timing was like another set of markers out when i first checked it, took it to adam and he set it 5deg btdc or whatever is stock for sr20's, there is alot of play in the timing at the moment and im not sure whether thats the way it should be....... |
A lot of play in the timing?
As in its bouncing around at idle and stuff like that?
Could be a faulty ignitor.. that´d cause those sort of symptoms.
Then again it could be a whole lot of other things... But ignitor are fairly easy to diagnose, especially if you have some spare ones lying around.
-ps, No worry´s Ken Fast performance. It´d take alot more than that for me to think someone is having a go at me.
I think the SR20DET is around 15 degrees BTDC
mmmm that interesting
there was alot of play when i first put the turbo on it, but it wouldnt go anywhere near 15btdc
| QUOTE (freddynolegs @ Dec 19 2004, 11:17 PM) |
| there was alot of play when i first put the turbo on it, but it wouldnt go anywhere near 15btdc |
Was it more retarded or advanced than that?
You did hook the MAP sensor back up right yeah, the computer needs that for timing...?
i connected it up the only way it will go, im not entirely sure, when you move the CAS which to advance the timing and which way to retard
correct 15 degrees for sr20s
Bit strange you should be able to get 15 degrees or more out of it, so what does it go to if you fully retard it and also what does it go to itf you fully advance it.
i cant remember off the top of my head, Whats normal for a stock car, and whats normal for a modified car are different things id imagine
if you can't get 15 degrees at all then you should tackle this problem first before you do anything else
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