98Z28CobraKiller

iTrader: (17)

We ended up deciding on the AEM EMS as the gotto aftermarket for some new setups that we have coming out soon. Because I am the designated tuner, one of these AEM EMSs was purchased for me and I have been tasked to learn it and tune the up and comers. Because my car is a known good running platform, we thought it would be best to start with my car. The other cars have been completely rewired and have all new stuff so that left too many variables.

So why AEM? Well, I believe that it's the only true standalone option that runs the factory gages. Everything else would require the stock computer to stay in the car to run the gages. It also seemed to have everything that we needed featurewise.

The setup:
98 Fbody
370ci LQ9 w/ AFR 225's and a single PT88 Turbo
80# injectors w/ brfpr
2 bar MAP
Livernois Stage 2 cam (232/232 595/595 114)
Truck Manifolds
Full 4" mandrel exhaust out the back
Th350 w/ rmvb and FTI 4000 stall
Dana S60 w/ 3.55:1 gear

First complication. This standalone is only made for 99-02 fbodies. So the first thing that we had to do was re-pin from the 98 pinout to the 99 pinout. This went surprisingly well and quickly as Steve did it at his work for me.

My first contact with the AEM was not a pleasant one. The calibration file that it came with was to fire up a stock car. My injectors were not listed in the injector wizard. I called the injector guys and manually entered the offset values that they provided. I couldn't seem to lean it out enough while keeping it running and my temper started to flare. Decided to take a step back and do some hunting around.

I brought the car home last Saturday and parked it for the 4th of July weekend. I have another friend (LoudmouthLS1) that also bought one of these AEM EMS for his 106mm turbo build. So he is following along and got me a better base tune from a guy on yellowbullet (Collinsautomotive). Last Thursday, I finally got a chance to load that tune in the car. It was alot closer than where I was IMO. It was a little fat but I tweaked it right out. Was able to do some driving around and make some wholesale adjustments to the VE table.

Any tips for quickly tuning the table by myself? Trying to do it a cell at a time is a major PITA. From what I was able to piece together from my conversation with the AEM guys, in order for them to add CAN (to work the gages) they dropped the automapping feature. Not sure if there is a way to turn off the O2 feedback, go drive and log % error and then lay them over the existing ve table. Once it's real close, then turn the correction back on and it should be dead nuts.

I am not real familiar with all the idle tables yet but I need to figure them out. Because I am running a completely manual automatic transmission (TH350), the car wants to deliver the same amount of air via the IAC whether in park or neutral. I am tuning the idle in gear as that is when it requires the most air. When I go to park, idle surges up to 1500+. Not seeing a table for IAC % vs over/underspeed error. Maybe it's called something else?

My actual idle in gear is rock solid now. I still have the transition problem. Specially on a hot start going from park/neutral to reverse. The load just wants to kill the car. O2 correction is working like a champ at idle (0% TPS) but as soon as I give it any gas at all, the O2 correction shuts off on me. I can't figure out what is causing this or what condition I am not meeting in order to enter the closed loop part throttle.

Any help or feedback is much appreciated.

bonnarls1

iTrader: (20)

someone should have some input on this we need the help!!!!

98Z28CobraKiller

iTrader: (17)

Still no resolution

05HD

The AEM EMS is one of the easiest and quickest standalone ecus around to tune.

I like to use a boost comp tuning method most of the time. Tune WOT at a specific manifold pressure and set up the boost fuel correct table to subtract fuel for vacuum and add for boost if FI. You can then have a much greater resolution tuning drivability if you still need to do any tuning after you have copy pasted the one WOT load line you have dyno tuned to the rest of the load ranges.

The ignition vs. idle trim table is a big help keeping automatics from stalling on garage shifts. It can react alot faster than any idle motor.

Closed loop max load can be adjusted to your liking in the O2 feedback settings but I would recomend keeping it turned off until you have a solid tune on it.

98Z28CobraKiller

iTrader: (17)

Then you haven't seen the XFI or BS3 because both are WAY easier than this thing. I have heard that it goes REALLY good with rice.

I am fairly well experienced with tuning these cars. I dont use dynos. I just work my way up using the kpa vs rpm as this is a true street car that sees lots of different boost levels on the street. I have access to some 5 mile flat straight aways without any traffic or side streets.

That's helping but it isn't enough on a hot start. I can live with it for now though.

The Fuel table is close enough that I drove it with out issue on Sunday all day. I put atleast 50 miles on her and saw all operating temps. If I can't get this O2 correction working, I am sending this one and Joe's back to them plus they will lose the sale of 2 more that I have waiting. This is what I told the Tech at AEM about 20 minutes ago when I talked to him. He couldn't figure out why it wouldn't be working.

When I initially spoke to AEM while considering the various different systems, they had 3 features that appealed to me.
1) CAN - operates the factory cluster.
2) Automapping - This feature would make tuning the fuel table at part throttle a breeze.
3) WBO2 Closed Loop Fueling - Self explanatory.

I found out after we already bought 2 of them that automapping was removed in order to make CAN possible. So one of the 3 deciding factors is history. If I lose CL fueling, might as well just keep the stock computer then.

05HD

XFI and BS3 are oversimplified for people who only know how to tune carbs. They annoy the hell out of me because they don't have any of the tables they actually need. Instead you get crap like "power valve fuel" and a car that runs shitty (for people who can tell the difference).

Intentionally shunning a chassis dyno as a tuning tool is more than a little laughable. Controlled, repeatable, safe and legal conditions are the very basics to begin tuning with.

You probably haven't even set up the idle properly, since you just loaded up somebody elses tune and leaned it out. Never mind the after start enrichment and post start idle offset tables.

If the feedback works at idle, it isn't a hardware issue, it is a tuning error.

Automapping is for people who don't know how to tune.

Closed loop WOT is again for people who don't know how to tune.

Sadly, you actually do have to tune the thing, or pay someone else who knows how. Same goes for the stock ecu (you just get a basemap from a team of OEM engineers to use as a crutch with the stock ecu). Real advantages of a standalone are things like anti-lag, nitrous control, 2 step launch control, boost control, top notch datalogging etc. You know, things that actually make the car faster, not make the tuners job do itself...

NicD

iTrader: (7)

The one thing I really dislike about the AEM is how flaky it is, otherwise it's got a great software interface and I do really like the boost comp features. You can do a tune quicker on an AEM than on any of the others if you know what you are doing with boost comp and keep the vacuum areas normally mapped non-comp'd for accuracy. Saying that closed loop WOT is for people who don't know how to tune is laughable since speed density is just an estimation and will never ever be 100% accurate all the time and it's a nice feature to have. Auto mapping makes things go faster and is NOT just for people who don't know how to tune. XFI and BS3 definitely have less tables to deal with which isn't always a bad thing seeing as how half the tables in the AEM are about worthless anyways depending on your platform. If you can't make an XFI or BS3 car run correctly and "non-shitty" than the problem is you as a tuner.

Lots of half truths and false statements in this thread.

Not sure I have any quick tips to make it run correctly unfortunately, it's just another system.

Frost

iTrader: (45)

For this platform you are stuck with cell by cell tuning. You can already see the issue with trying to drive and tune this. You need to rent some load dyno time and do some steady state work. It will get this done much more quickly than driving around. If you are used to tuning the OEM PCM this won't be too hard since you already know what the motor wants and when.

05HD

Speed density is just an estimation? Just as much as MAF is I suppose that is true. Lean on an O2 sensor if you want (instead of tuning it properly), just don't get mad when you have to do an engine rebuild every time a wideband craps out from lead fouling.

You tune with auto mapping and I will do it by hand. I will be done first, with better results than you every time.

Re Big stuff: How are you supposed to make a car run properly with no air temp timing correction? I will answer for you- You can't.

Re FAST XFI: You get a spark vs. air temp table but no spark vs. coolant temp or even spark vs. start time.

These are just examples off the top of my head. Maybe this is why speed density is "just an estimation" to some people and others have no trouble tuning a car to run perfectly in all conditions with it. Crappy tuners and people who aren't picky about how their car runs will not notice this sort of stuff because they have no idea there even should be adjustments made for things they have no idea about in their estimated tunes.

98Z28CobraKiller

iTrader: (17)

Wow, glad to see that I have stumbled upon the tuning god in my thread. O5HD, who are you? It shows that you live in Tampa. Are you on the need2speed forum? What sort of cars do you tune as I would think that I would know who you are if you do any kind of LSx tuning from Tampa on south.

It seems that you are under the wrong impression with regards to my level of competence or the other 2 guys that just chimed in here. Atleast as it pertains to this specific LSx platform. I will gladly admit that I am just learning this AEM EMS but telling me that it's a tuning error without telling me what could cause the problem is no help at all. That's pretty much what the AEM guy said. So instead, how about you tell me how it should be setup in order to work properly? I am going to do some logs in a bit. Feel free to review them and critic. Maybe in seeing the logs, I may figure it out myself. I think that it is related to the advance idle feedback options setting somehow as I have tried all combinations of 02 feedback settings options without any success.

NicD

iTrader: (7)

Oh boy, the tuning god has spoken. Not sure why I'm going to dignify you with responses but these are too good to pass up.

Uh no, a MAF actually reads airflow. Maybe you need to brush up on the basics before you make an *** out of yourself?

Who doesn't take note of how long an O2 has been in use when running leaded fuel and pay attention? There are other fuels out there other than plain leaded as well so not sure what your point is. There are limits for a reason on correction and should be set appropriately in case of failure anyways.

Another LOL, automapping can be a benefit and will work faster than you do by hand not to mention most professional tuners just use it to rough it in with manual fine tuning afterward. Let's not pretend you can swipe a keyboard faster than a computer.

Never said those tables wouldn't be helpful but if you can't figure out how to work around those limitations than it's your problem.

Huh? Speed density is a computer estimation no matter what ECU you are running. Plenty have no problems at all tuning an XFI or BS3 ECU yet you seem to blame the ECUs for not being able to be tuned, ever think the problem might be you?

Ever think that real tuners know how to get around those issues? And why are you trying to be so smug talking about estimated tunes when you clearly are not understanding my point in saying speed density is estimated fueling to begin with?

NicD

iTrader: (7)

Best thing you could do is post up the cal file and logs for people to help with, otherwise we are shooting in the dark.

Frost

iTrader: (45)

I would turn off all of the box's correction until you get the base tables pretty close.

98Z28CobraKiller

iTrader: (17)

I'm just starting to play with the logging software now. I dont give a **** what anyone says. tuning cell by cell driveability by yourself is super cumbersome in real time. I have to see if it's possible to setup a histogram that will allow me to see the % error vs target average by cell against the Fuel table breakpoints (kpa vs rpm).

I totally agree that the fuel table has to be close in order for the O2 correction to work best but I just want to see it work just to make sure that it does. Call it peace of mind.

Here's the cal file. Just change the .hpt extension to .cal as it wouldn't allow a .cal file attachment.

98Z28CobraKiller

iTrader: (17)

Also, in reviewing some of the data that I acquired today, Apparently, it is not the TPS going over zero that is knocking it out. The threshold seems to be at 5% and 2000 RPM which is exactly when it transitions into idle feedback when below both of these values. The problem is that as soon as it goes above either of these values, ALL the O2 feedback stops working. In the parameters window I am seeing a solid "O2 FB Status" whenever it isn't working that supposedly corresponds to a binary value that they dont tell you what it is. And the "O2 FB Clear" goes from "OFF" to "ON" when it stops working. So it's clearing the feedback out and exiting IDLE FB but not starting the normal O2 FB.

Just though of something that I wont be able to test until later or tomorrow as it is raining heavy here now. Is it possible that because the IDLE FB Max is set to 2000 RPM and the O2 FB Minimum is set to zero that the 2 modes are overlaping and since it never crosses that O2 FB minimum threshold after exting the maximum idle threshold RPM, it never starts after the clear?

05HD

Here are a few basic pointers from taking a glance at what you posted:

1. Try setting the o2 feedback RPM limits to something a bit more reasonable like 500 rpm and 6200 rpm.

2. You have it set to inhibit o2 feedback any time accel or decel fuel is triggered. O2 fb clear on means it is holding the feedback for some reason related to your settings. Need to see data from running car to see which one.

3. +/- 20% is quite a bit of feedback leeway especially since you want to use it @ WOT

3. Your idle % vs target table is all over the place. It should move in a close to linear fashion as the idle motor airflow does.

4. You have no throttle follower set up to open the idle motor with the throttle.

5. You have no start extra fuel at operating temperature. It needs some.

6. There are obvious errors in the main fuel map. Those need to be fixed before even thinking about turning o2 feedback on.

7. It will definitely blow up if it goes over 9 psi of boost on that tune.

8. You are obviously out of fuel map resolution in the low rpm and high vacuum areas. Switch to a boost comp tune and adjust microsec/bit down to gain resolution.

9. Injector battery offset table looks highly questionable. Injector response is completely flat from 12-16v?

05HD

It is obvious from reading your reply that you have no knowledge relevant to this conversation. I will not waste any more time responding to you.

05HD

No need to worry about who I am or what I have tuned. I came in here to help you and you have done nothing but attack me. I'm still in here trying to help you but you have to help yourself some. See my post above.

Oh yeah, idle feedback and o2 feedback are 2 entirely different things. Idle feedback is closed loop idle RPM control. O2 feedback is closed loop A:F ratio control.

98Z28CobraKiller

iTrader: (17)

Thanks for the info. Not sure if you read all the way thru my first post but due to the bad luck that I had with the first unit having an issue out of the box, I have concentrated on getting the very basic things going and just verifying that everything works. I can assure you that I have tuned enough fast cars to know that I cant go WOT on this tune the way that it sits. I haven't even started working on boost fueling yet or anything over 4K rpm and as I stated before, O2 correction will be shut off in order to fine tune the fuel table,

Next up is learning how to manipulate the Log software and setting up some usefull graphs. I can't seem to find any preconfigured histograms.


I got an email response from AEM Tech support today after they looked at the log that I did yesterday and the tune.

[QUOTE]Carlos,

It appears the noisy TPS signal is false triggering your accel fuel causing the “O2 FB Cleared” to stay ON anytime you are on throttle disabling the O2 FB.

Go toà Fuel à Accleration fuel à throttle accel à Options / throttle accel.

Raise the Accel dTPS Trigger from 10 to 12 and keep raising the value until the parameter “Accel fuel” doesn’t false trigger. Be sure to hit “enter” after change any values otherwise the EMS won’t update the system.So as soon as the rain stops and it dries out a little, I'll try it out. I new that something was flaky.

98Z28CobraKiller

iTrader: (17)

Also, with regards to the boost comp tuning method. I've never done that before but will it work with a boost ref fuel pressure regulator? Vacuum is already pulling fuel pressure and boost is already adding it.