patman

iTrader: (3)

Hi guys,

I thought I should post up a few of the things I have learned since installing the AEM in my car.
First off, my setup is as follows:
PFS streetported motor (bought it this way, no details)
Borg Warner S200SX 56mm, FMIC, 3" DP, high flow cat, apexi catback
Currently running 11-12psi on wg spring
Stock Injectors, stock FPR, Walbro 255
MOP and AC operational

I have just finished putting together a good basemap, and am about to start pulling fuel, so I think now is the best time to post this in case anyone wants to use it. I would consider this a pretty conservative map, but obviously, it is only a starting point and its safety must be verified for your particular engine.

On top of that, here are a few general things I have noticed and/or griped about since installing this ECU. Note that most of these issues are already fixed in the attached cal, but should be checked/addressed on first install:

1) When editing values, you MUST hit enter after typing into a cell or your change will be rejected. I had a pertty hard time zeroing the base timing until i figured this out. Speaking of base timing, the FD does not have a TDC mark, so you will need to find a sneaky way to check it. I used trailing#1, with timing locked at 5* and timing difference table set to -20 everywhere, but there are other ways.
2) If you hear a clicking from under the hood with key on, you likely are running the wrong MOP calibration curve (base cal works for some people,others not) there is a thread here and on AEM forum with correct numbers.
3) AC settings on my unit were totally wrong, causing the AC to kick on at random times, see my cal or threads on AEM for fix.
4) DO NOT try to drive your car on AEM's basemap, it is TERRIBLE
5) There is not an option for the stock RX7 injectors in the battery offset wizard menu, but the 30-1800 base cals do come with the correct curve, so don't mess with it if you have stock injectors
6)Injector staging on the AEM cal is WRONG for stock injectors, staged flow ratio should be -35, values on difference map should be 60, anywhere you are in boost. I like to ease the transition, so I go from 0 to 20, then 60.
7) It is imperative to check the value for o2 #1 gain: unless your wiring or sensor is crap, this value should be 1.0 or very close. AEM's map had it at 1.55, which totally screws your readings.
8) If you are unable to set AFR values to anything leaner than 9.68, it means that your ECU has defaulted to Methanol as the AFR unit, which is a retarded thing to default. To fix, go to configure>units>AFR units and pick gasoline. It may be necessary to pick something else, click apply, then switch back to gasoline, and apply again.
9)AEM's trailing split table sucks, and should be changed
10) It is a good idea to disable most of the fuel and ignition trim options for the first few tuning sessions.
11) that said, AEM's idle values are a little strange and need retuned, but once set properly, the idle function works pretty well. You will need to retune the warmup enrichment tables too, they don't add nearly enough fuel.
12) Be careful when tuning, the percent change option is what I mostly use, and it is easy to forget that it is based on the current value, ie if you want to add 10%, type 110 into the box, and to subtract 10%, type 90.
13) I find that I like the feature that allows switching from table to graph display and back; I do all my tuning numerically in table mode, but then glance at the graph to check for outliers or areas that need smoothed.
14) the AEM setting for the radiator fan comes set to 176F, which is too low if you have a stock 180 thermostat, to modify it go to Options>configure outputs, and select LS8.
15) It is a good idea during tuning to enable knock control (setup>sensors>knock sensor), and set the 'knock ign retard max' variable to a relatively high value, just in case you make a mistake.
16) Make sure to check the accel pump values, as this can cause a headache tuning if it is wrong. I usually start with it really high, then take a log with a lot of dTPS, and dial the value down until I don't see a rich spike anymore. I haven't got it quite right on the attached cal, but it is ok for starting.


That's all I can think of right now, I will add a post at a later date on setting up boost control, but I need to spend a few hours tuning first.

Feel free to comment on the above or on the attached cal.

Pat

arghx

iTrader: (3)

Thanks for posting that. One thing with the idle you could try messing with is changing the "Idle PW frequency" from 488hz to 244hz. 244hz is the spec given in the service highlights document for the FD. It might make a difference, it might not.

I agree that most guys will be better served by leaving the boost compensation fuel table zero'd out, at least for initial tuning. It is faster but it also has a lot less resolution.

Your timing maps look great for a starting point. Note that the Knock Sensor calibration table determines the baseline noise threshold. Voltage must exceed that value first to be counted as "real" knock voltage. Then you use your knock control options to figure out how much timing is pulled per volt above the noise threshold. What this means is that you can adjust the calibration to account for resonance and other noise-prone operating conditions.

The ignition vs idle rpm table can be used to stabilize idle speed in addition to what the idle control valve is doing. You can also use the "high idle" setting to help temporarily raise the idle on deceleration. This can reduce the chance of stalling--it functions like a dashpot.

Under ignition trims you can set the air and water temperature compensation tables to pull timing if the engine starts to run hot.

In my experience with the AEM, it is good to use the dTPS table with live tracing to tweak the throttle response, provided that your main fuel map is decent.

What boost control strategy are you intending to use? You can start with open loop control just to get a feel for how the system is responding.

Thanks for the advice on injector setup and staging.

patman

iTrader: (3)

Thanks for the comments.

I am using the AEM provided knock calibration table, as I don't like any of my options as far as a calibration strategy, and their numbers seem about right based on my datalogs.

I will try changing the idle PW frequency, but my idle function actually works great now that I tuned it, I was simply commenting that AEM's numbers were pretty far off for me.



I would like to make this thread a good reference so that people first starting with the AEM have somewhere to look for info, so does anyone else have good beginning points to add?

GMO-RX7

iTrader: (21)

Thanks for sharing Pat. Do you have any updates?

patman

iTrader: (3)

Not yet, I took the car apart to fix an exhaust leak and add EGT probes, as well as plumbing the wastegate into the downpipe and doing my 2-stroke MOP mod. I am finishing all that up this weekend, so I will start dialing in the tune next week if the weather is OK.

I am also going to add boost control next week.

GMO-RX7

iTrader: (21)

Cool. I haven't got my car going and been able to tune with it at all yet I was just wondering how it was working for you. I currently have the stock injectors to break the engine in with so I might use you're base map.

patman

iTrader: (3)

I put about 1000 miles on it with basically that map. I pulled a little bit of fuel from it, but the car ran good with no major issues, although it is still way rich up top. I didnt want to pull any more fuel until I had the leak fixed so I could be sure of good AFR readings and the EGT being logged.

GMO-RX7

iTrader: (21)

Yeah, I dont know how well it will work with mine. I have a bridgeport engine I bought it like that same as you, single turbo, stock injectors, stock fpr, and a walbro for now. I have a s5 na vert I am thinking about getting a patch harness and learning how to use the AEM on that car first. I have never done any tuning but I would like to do it myself if possible. What prior experience do you have? I see you're cars in you're sig.

EB Turbo

iTrader: (1)

Because the FDs have the idle adjustment screw the Idle% V Target table is really dependent on where that screw is. If the screw is too far in You will not have proper idle control above 1700-2000rpm. If it is too far out It will not have idle control in the 700-1200 range. There are many other parameters that need to be adjusted to make the idle control work really well. I always verify/set the idle screw in the same position before tuning idle control.

There is actually a lot of good information out there on setting up these systems. Some pertaining to the FD specifically and more on how the EMS needs to be set up. Understanding the Microbit/sec scaler, Staged injection control, advanced boost targeting/control really goes a long way.

EB Turbo