AFC-SplitSecond PSC1 Map Library

[SpeedAdiction20]

I was having a similar problem, unfortunately I can't really remember exactly what the problem was, I think it had to do with my MAF, do you have a relocated MAF sensor, if you don't and have a FMIC, then I HIGHLY suggest relocating it, I had so many problems tuning the car before I relocated the MAF, you can do it with a smic, but it is harder usually since you don't have the room with the pipes, or usually the smic pipes are not basic ones you would buy from anywhere, (usually custom to the msp is what I am trying to say, and they are expensive)

but ya, after I did that, it ran so much better, and it was much easier to tune the car after that, you will always have stumbling, at least a little bit unless you relocate the MAF.. also when you tune, get your basic 3rd gear pull down, and get the main spots changed that you want to do, also when you shift after 3rd gear pull, don't hit the gas after that, just let it cruse, at least when you are tuning and datalogging, then once you have that set, work on the different areas in the rpm range, I did it by making a bunch of runs by lightly boosting and slowing gaining speed/rpms, and did that at different rpm ranges, I also did one where I held it to 1-2-3 or so psi throughout the whole rpm range, so that when it simulated me highway driving or something like that, and not wanting to go full boost, but going up a hill or something, I always noticed that my car would bog down a lot in low psi, but the higher rpm, but be very careful leaning out anything in the high rpm, keep it to 11 afr around 6.5k rpm and lower 11s from 6-6.6k rpm (remember it will show up as 7k rpm on the cell for the SSafc maps, because they represent the rpm or value up until that rpm point, it is hard to explain but I am sure you figured it out once you try to match the boost and the rpm with the afr levels together)

but thats generally it for now I would say, not sure if I said it all correctly, like I said it is hard to explain all at once, but I wrote a bunch of this stuff and more detailed stuff a while back, like maybe last year, did it a few times for different people, but since Wagonbacker isn't a msp mod anymore, there hasn't been anyone to help with the forums and especially keep this thread clean and organized and easier to read, but oh well

 

[MSP2k3]

Thanks, yeah I have had the MAF reloacted for about 2 years now, I agree, the car ran much better this way. I'm just taking baby steps, trying to get around 12:0 from 3-5k and closer to 11:0 to redline. But like I said, the main part I was struggling with was it dumping fuel in between shifts.

Gonna load up slo03.5's map here in a min and go from there.

 

[SpeedAdiction20]

ok then that is good, like you said, (and I didn't really notice that you had it right when I replied before) but there is a lot of fuel in the lower psi at higher rpms, do what I said and run a bunch of datalogs with different, low, psi throughout the rpm band, it will make a huge difference the way the rest of your fuel map will work, because of all the fuel being dumped early on, it tends to make the rest of the fuel map kinda jumpy, once I smoothed out the lower end, the rest was much easier to fine tune

 

[MSP2k3]

Sounds good, another thing I am sort of confused with is open loop/closed loop.... i know the difference between the two and understand what they are but I was under the impression that you could only tune open loop (4kish rpm and above), as the ecu will readjust itself during closed loop. Am I wrong in assuming this?

 

[justanothermp5]

you can tune anything with the SSAFC, closed loop/open loop doesnt matter,
if you adjust a cell on the map, it will adjust it

 

[Wagonbacker9]

you can tune anything with the SSAFC, closed loop/open loop doesnt matter,
if you adjust a cell on the map, it will adjust it

you can't adjust it if the ECU is actively changing fuel trims based on 02 readings and not using a preset map.... what do you think closed loop is?

Sounds good, another thing I am sort of confused with is open loop/closed loop.... i know the difference between the two and understand what they are but I was under the impression that you could only tune open loop (4kish rpm and above), as the ecu will readjust itself during closed loop. Am I wrong in assuming this?

This is correct. In open loop, the ECU is adjusting fuel for what the O2 sensor is reading. Most of the problems arrise because when our ECU tries to switch and its mid-adjustment, it freaks the hell out. basically setting your overpressure and map settings is helping to work through that transition smoother.

 

[justanothermp5]

what? I just said it doesnt matter, and im talking from personal experience

EDIT: and since i know you'll probably argue. Ill give an example. My car would run super rich on cold starts. like 10 AFR's at idle. Once it warmed up it would go to 14.7 but as soon as I touched the gas it would go straight to 10. So i tuned at idle and all of the vacuum range. Now on cold starts (when the car is in closed loop) the readings are 13-14, if the SSAFC doesnt effect anything in closed loop, how would changing the cell values have done this? EXACTLY

 

[SpeedAdiction20]

ya I've always been unsure of how exactly the ssafc can tune in vac. my thought was that you just forced the car into open loop, but that doesn't really make sense, and ya, like Wagon said about the transition, I had mine originally set to -1psi, but I found that to be too low just because when I would highway drive and was going up a hill, it would switch back and forth and make it run rich, so I set it to .2psi, which so far is working great, it allows me to tune the low psi in higher rpm ranges

 

[slo03.5msp]

Maybe you have a stuck egr and sometimes it closes on cold starts and sometimes it doesn't. However if you try to tune in vacuum and you have not set your unit up to do so it will immediately idle lean. Straight red 17's i experienced this while trying to pull a little out of my 440's. If you have your ssafc set to on at -20 you can tune all through there. However if you try to do that I would recommend renting a dyno. That would be the best way to do it.

 

[SpeedAdiction20]

^^ that's what I figured, just wasn't sure about it, makes sense

 

[justanothermp5]

Maybe you have a stuck egr and sometimes it closes on cold starts and sometimes it doesn't. However if you try to tune in vacuum and you have not set your unit up to do so it will immediately idle lean. Straight red 17's i experienced this while trying to pull a little out of my 440's. If you have your ssafc set to on at -20 you can tune all through there. However if you try to do that I would recommend renting a dyno. That would be the best way to do it.

My EGR isnt hooked up, so no
my SSAFC is set at overpressure or RPM, and its set at -1psi, so not sure what your talking about....but it none of it applies to me I guess

 

[MSP2k3]

My EGR isnt hooked up, so no
my SSAFC is set at overpressure or RPM, and its set at -1psi, so not sure what your talking about....but it none of it applies to me I guess

supposedly, since your overpressure is set at -1psi, your AFC is not making any changes until the internal MAP sensor reads -1psi.... at least thats how i understood it?

 

[justanothermp5]

exactly, thats how it is widely understood, but not how it actually works.
This isnt the first time ive added fuel below the, "activation point" i guess u could call it
I had a huge vac leak when I first went turbo, my car would randomly stall out at idle. So i added fuel at idle to stop it from stalling, even though my overpressure or RPM was still set at -1, it added fuel anyways. So im not really sure what those settings are for, but I dont mess with them anymore

 

[SpeedAdiction20]

those settings are when it forces it in to open loop

 

[justanothermp5]

if its using the readings in vac, then its obviously already in open loop....

 

[719prottege]

So heres a question.... When I floor it from a stop or downshift and floor it I get decent 10.8-11.7 afr and pulls great. If I for instance am cruising at like 4k and roll on the throttle in like 4th gear it runs kinda lean like 12.5-13.0. So I guess low rpms high boost is the problem. Any advice on how to tune this out?

 

[SpeedAdiction20]

do what I said a few posts back, slowly increase speed, so that your sitting at different low psi throughout the rpm band during your pulls, do it for each of the lower psi, generally, so you get the afr for each low psi throughout the entire rpm range, works wonders when smoothing out your tune

 

[MSP2k3]

do what I said a few posts back, slowly increase speed, so that your sitting at different low psi throughout the rpm band during your pulls, do it for each of the lower psi, generally, so you get the afr for each low psi throughout the entire rpm range, works wonders when smoothing out your tune

Yeah, this has worked well for me.... held it at around 2-3psi all the way to redline, and tuned for it, then tried 4-5 and tuned for it, rinse and repeat.

I'm still have plenty of rich spots, but i just need to find the time to spend an entire day and try and knock it out. I will say, the car pulls like a freight train at 13.5 psi lol.

Side Note: Went to my first autox event this year yesterday..... first run, 13psi = no traction. Ended up with the boost turned down to 6-7psi in order to acutally use the throttle.

 

[jdwk]

Does anyone know what modification the SSAFC is actually doing to the O2 past the trigger? Is it outputting a constant voltage? Is it outputting an offset voltage? Is it outputting a wave with a specified mean?
With the AEM I have all three options. Seems like offset works the best, but was curious what the SSAFC uses.
It would be nice if someone had a plot of the OBDII O2 sensor reading, but even I haven't found decent software that does that yet.

 

[Carlinator]

Been running the stock AFC map for the last few weeks, and I'm getting ready to start tweaking it to my setup. I've read a lot of advice about tuning light-throttle and such, but I was wondering: All this talk about setting the overpressure to -1 or whatever, is that for anyone doing their own tune, or just if you've got larger injectors in? My car is stock aside from the exhaust, so I'm trying to figure out my best course of action here.