Tweecer FAQ Sheet


TwEECer FAQ Sheet

I wouldn't think it would be necessary to say this, but the following tuning suggestions only apply to 94-95 year model cars. Also, please keep in mind, these are just my opinions and findings through my experimentation and reading for countless hours on the TwEECer website. I have never worked for Ford, I have no mystical insight into how the EEC functions. Also, there are several ways to accomplish the same thing. What may work for one guy may not work for another. I think everyone should read the available documentation on the yahoo TwEECer site, they are downloadable .pdf files that are full of good information. Even if it doesn't always directly apply to our cars.

General Info:
Here are a couple of basic guidelines to follow:
1. refresh the screen before moving on. A lot of times the TwEECer will reject what you have entered. If you are modifying a scalar there is a refresh button on your screen, I suggest you use it after every entry. Fuel tables and some scalars will round your values down the the closest value it can accept. For example, if you put a 12.1 in the fuel table, once you refresh it will change to 12.014. I can't tell you how many times someone has complained that their car wouldn't run just to find out that one of the values in their MAF transfer had changed to a 0. Everything needs to be double checked before writing to the chip.
2. Backup your tuning frequently, after a small mishap were I had to start all over, the file got corrupted somehow, I learned that it is very important to back up your TwEEC's. I save a new file for every couple changes, but I am a little anal too.
3. Use the Tuning Notes in the "Input/Output" tab, you are going to forget some of the changes you have made.
4. Compare different factory EEC calibrations, there has been a lot of success in using a modified version of the Cobra(J4J1) cal. There is a ton of differences between the Gt and the Cobra cal.'s.
5. When installing the TwEECer software, always install the Borland database software first.
6. Position 1 is full Counter Clockwise the one with the dot if you have one. Off is full clockwise
7. Set your base timing by the distibutor back to 10*. All of the timing tables in CalEdit are based on 10* base timing and it is included in the values you see

Getting Started:
1. Once you have your TwEECer hooked up and all of the software properly installed. Your are ready to try your first tweak. Be sure to turn the car to the "ON" position, but not running, anytime you are trying to read or write to the twEECer while it is connected to the EEC. You desktop PC users don't need to worry about this, as I believe when the TwEECer is not connected to the EEC it is bus powered by the USB cable.
2. Open CalEdit, go to the Input/Output tab, the TwEECer knob can be in any position, click read EEC, this should populate all of your scalars, functions and tables with your stock configuration. If you want to use a cal. other then your factory, you will have to download it from the TwEECer website, then using the Input File button, navigate to the .bin file. Make sure in the file type drop down menu you select Ford EEC binaries.
3. I would make a small change, something immediately noticeable like the idle RPM or Fans, save the change by clicking on the write changes button.
4. Now select one of your 4 available tuning positions on the dial selector and check write TwEECer. There are a couple of extra steps for datalogging, but I will get to that later.
5. Now its time to verify that your TwEECer is working by selecting the position you just wrote to and starting your car. You can switch between 2 different tunes while the car is running. Go ahead give it a try, switch between the factory cal and the one you just wrote, and watch you idle go up and down. Now you are ready to try datalogging, if you bought the RT model.

Note: This assumes that you have a working and installed TwEECer on your car and that you are using CalCon/CalEdit v1.20b or newer.

1) Connect the USB cable from the TwEECer to your computer.
2) Startup CalEdit.
3) Click the tab labeled "Utilities" at the top
4) The top right of the screen contains the various variables you may datalog (you may select up to 16). Select the items you would like to datalog.
5) Click "Payload".
6) Click the tab at the top labeled "Input / Output".
7) Check the box labeled "Data Logging" which is right below the button called "Read EEC".
8) Turn the key in the ignition to the ON position and wait 5 seconds (so windows can have time to load the USB driver to talk to the TwEECer).
9) Click "Write TwEECer".

* wait for CalEdit to write the binary and payload to the TwEECer *

10) Close CalEdit and Startup CalCon (CalEdit cannot write to the TwEECer while CalCon is open).
11) Click the tab at the top called "Dashboard" or "Digital" (doesn't matter which, just pick whichever display is preferable to you).
12) Select the correct RT Method (pick from list under "Log to File" checkbox)
13) Check the box labeled "Log to file" in the top right hand corner.
14) Start the car.
15) Click the button labeled "Start Logging".

The gauges in the display should now spring to life showing you the various items you selected in your custom payload. If it does not, or very strange values show up, please make sure the connection with the J3 port on the EEC is clean, and that you followed the steps above correctly.

Important Payloads:
This varies from one setup to another, but these are the ones I always datalog, when trying to tune my car.
Actual Load
Air Charge Temperature (ACT)
Engine Coolant Temperature (ECT), when it is fixed
PW one or both
KAMRF 1 & 2
Lambda 1& 2
MAK Voltage
O2 sensors - both
Spark Advance
Throttle Position Sensor

Basic Tuning:
Checksum Base Address = 0, this value must be inserted in the scalars or the EEC will trip a CE light once you have modified the EEC.

How to remove the spark retard between shifts.
Under the Scalars tab locate spark_min_for_tip-in_retard, the current value in this cell should be 5. You should change this to whatever value you feel comfortable with. I typically set it to whatever my total spark advance is. The blower and NOS guys should use some caution here as whatever value you input, the value you enter here will be your total spark advance for about 3/10th's of a second during any shift, even powershifting. I used to tell people to bypass this, just keep your foot to the floor, I have since datalogged powershifts where the retard occurs. I also used to tell poeple that this feature doesn't really do much. since it is only active for a short period of time, but after having to go back to stock programming for a week or two, I can honestly say that there is a seat of the pants difference when you shift. Wether or not this translates to quicker E.T's I can't say.

There are 2 fan speeds to concern yourself with, low and high, so be sure to adjust them both. I guess you could run the high fan all the time, but with us already having to go to the dealer to keep our cars from catching fire from the fan, I don't suggest it.
Since I have a 180* thermostat I generally I use these values;
Tailor the fan settings to meet your needs.
fan_high_speed_ECT1_on = 196
fan_high_speed_ECT2_on = 200
fan_high_speed_ECT_off = 190
fan_low_speed_ECT_off = 182
fan_low_speed_ECT_on = 188
I haven't found it necessary to mess with any of the other fan settings

there are 4 spark tables to look at;
spark_MBT_table - contains what the factory believes will make the most power. I set the values in this table to mimic my spark_altitude_table
spark_altitude_table - at higher altitudes you need more spark advance, set this table to mimic your spark_base_table +2.
spark_base_table - this is the table you will do most of your TwEECing
spark_bdln_table - this table is the maximum allowed spark, regardless of what you enter in the other tables or multipliers. I set this table to all 55's the highest number that CalEdit will accept.

Fuel tables: The values in the 2 load based tables are your target A/F ratio. Please note there are several modifiers to these tables, I will post a list on how they interact in the future.
fuel_table_base_OL - This is the base fuel map used until the ECT stabilizes, the temperature in which the EEC stabilizes is adjustable through a scalar, stabilized_min_ECT. The lower the value in that scalar the sooner the EEC switches from the base table to the stabilized table.
fuel_table_stabilized_OL - This is the table you will use to dial in your A/F, once your MAF transfer has been set.
fuel_table_startup_OL - The time based values in this table are subtracted from the load based values in the other 2 tables to enrichen the mixture during cold startup. The higher the value in this table the richer the startup mixture is.

Basic Scalar changes:
EGR Switch Type Scalar - Values

0 = EGR is working and accessing its tables (DEFAULT)
2 = EGR is disabled and bypassing its tables

Thermactor Present Scalar Values - (A.K.A. Smog Pump/Air Pump)

1 = Thermactor is present (DEFAULT)
0 = Thermactor is disabled

MAF Voltage Min = set to 0 or close to it, like .02
MAF Voltage Max = set to 4.999 - this gives you a little more headroom for cars with a blower, they will easily max out a factory MAF meter.Probably doesn't help performance, but will help from triggering a CE code.



08-06-2003 12:19 PM


MAF Transfer
To keep this from being 100 pages long I am going to post a website that explains the MAF transfer very thoroughly

Injector Slope High = Actual Injector Flow rating, taylor to meet your needs
Injector Slope Low = This is generally set to 1.2 x High Slope. When using a Cobra cal. I tend to use the same slope for both, just because Ford did.

open_loop_delay_hyst = 0 , this will allow the EEC to use the OL tables immediately when other criteria are met.

Dont forget EGR and smog pump switches (A.K.A. Thermactor). These are found in the scalars.

EGR Switch Type Scalar - Values

0 = EGR is working and accessing its tables (DEFAULT)
2 = EGR is disabled and bypassing its tables

Thermactor Present Scalar Values - (A.K.A. Smog Pump/Air Pump/Pollution Pump)

1 = Thermactor is present (DEFAULT)
0 = Thermactor is disabled
--Couple definitions--

-Base Altitude Spark / Base Spark Table= A higher number increases ignition advance and a lower number decreases ignition advance. Base and Altitude spark tables are used based on barometric presure. Berometric presure above 26in/hg and the EEC will use the Base Spark Table while a barometric pressure below 26in/hg will use the Altitude Spark Table.

-Global Spark Adder= This scaler function allows ignition timing to be adjusted. Increasing this value above 0 advances ignition timing by adding an aditional amount of timing to the spark table values. This is the same function as if you were to turn the distributor to advance the timing. These values can also be in the negitive to decrease timing.
Example: Global spark adder= 2 , this would give you 12* base timing( if the distributors at 10*)
Global spark adder= -2 , this would give you 8* base timing( distributor at 10* base)
*All the EEC calculations are based off of 10* base timing*

PIP / PIP Filter= Lower number gives a higher Rev limit.
PIP= 6006250/maxRPM
maxRPM= 6006250/PIP
PIP= 961 max RPM= 6006250/961= 6250

PIP is a sample rate frequency that limits the PCM program operating loop to a minimum rate. If the loop is sampled less then PIP times within one operating cycle( 2 crankshaft revolutions), the PCM limits RPM
( and thats how you come up with an effective rev limiter)

-WOT Fuel Multiplier vs. RPM= This is an open loop fuel adder. Increase value over 1 to lower injector pulsewidth( less fuel) and decrease the number under 1 to increase the injector pulse width( more fuel) during open loop. Now, if these are untouched, you might find there are no RPM values on the X axis. Simply input the RPM values and corasponding fuel multiplier values below (Y axis) You can change the RPM value to add or remove fuel at any specific RPM.

-Lambse= is what the EEC is targeting as air fuel ratio at anyone instant. If it is targeting 15.7 that means your running rich at that instant, so it tries to lean it out by targeting a value higher than 14.7.

-Kamrf= is a long term correction. If it sees at a particular condition it is always running rich or lean it will start correcting it with Kamrf. It is more of a fuel multiplier than a target. If it is running rich at a certain condition the Kamrf will be less than one. (normal fuel times number less than 1 = less fuel).

-Injector breakpoint= Injector breakpoint is the point at which the eec goes from the high to the low slope.
The units are pound mass of fuel per injection. The injector breakpoint is an adder for the final fuel calculation to
account for the non-linearity of the injectors, especially at small pulse-widths. It is a time-based adder, so it adds less as the PW gets larger. The breakpoint is used on the dominate slope at idle ( can be low slope or highslope) if your PW at idle is below 2MS, low slope is used, if your PW is above 2MS then the high slope is used.
Low slope and injector breakpoint are open loop fuel adder's below a pulse width of 4MS. Low slope is used from 2MS and below and the Injector breakpoint is used from 2MS to approximatly 4MS.The Low slope isn't related to Injector breakpoint in any way.

--Some basics--

--Eliminating speed limiters--

(entering 16383 for all values effectivly turns off speed limiters)
- Speed limit stage 1 off = 16383
- Speed limit stage 1 on = 16383
- Speed limit stage 2 off = 16383
- Speed limit stage 2 on = 16383
- Speed limit stage 3 = 16383

--Raising rev limits--

( pretty obvious what this does, taylor to your needs, but remember to always set the "on" value higher then the "off" value)
- Rev limit 0 off = 6300
- Rev limit 0 on = 6400
- Rev limit neutral 0 off = 6300
- Rev limit neutral 0 on = 6400

--Longtube header settings--

( if youre running longtubes, you might have ran into some problems with the O2's going cold, or taking a while to heat up to temp, these settings should keep everything happy)

Exhuast Pulse Delay

900 1300 1500
.075 - 24 24 24 24
L .06- 24 24 24 24
O .05 - 20 20 20 20
A .04 - 20 20 20 20
D .03 - 20 20 20 20
.02 - 20 20 20 20
.01 - 20 20 20 20
.005 - 20 20 20 20

--How to calculate Throttle presure(TP) from an AD count--

( typically in your settings that involve TP, TP is not displayed in volts.. Insted its displayed in an AD count, for example 100, 252, 332, 600, and WOT would be 1020( 5 volts). So to find out the TP voltage at that AD count, use the formula below) The AD # at idle is right around 200 (.98 volts) AD # around a 1500rpm cruise speed would be
To convert the Throttle position AD count ( throttle position in AD counts) to throttle position volts divide the TP number by 1020 then multiply by 5 like this..

Examples: 1020/1020*5 = 5v
640/1020*5 = 3.137v

--How does the Switch work? Which tune and im running on on which setting?--

Full CounterClockwise

A - tune 1 (Switch points near dimple on the case)
B - tune 2
C - tune 3
D - tune 4
E - Tweecer OFF (stock calibration)

Full Clockwise

--AODE Settings--

trans tv adder 1-2 =16 ( Trans TV adder, is an adder to the trans presure)
1-2 time=0 ( time delay between shifts)
tv adder 2-3=16
2-3 time=0
tv adder 3-4=20
time 3-4=1 (Lower this value to make the 3-4 shift quicker. Units i believe are in seconds)

-- WOT shift points--


take note, the actual 1-2 shift is going to be around 1000rpms off, from the setting you enter. The 2-3 shift is around 500rpms off from the set WOT shift point. So if u want the actual 1-2 WOT shift to happen at 5900 rpms, you would enter 4900rpms for the 1-2 WOT shift, and so on. This is dependant on which gears you are running.. SO the higher the gear( 410's-up) might require an even more drastic change.

--Setting the tranny to shift firmer--


( entering higher numbers on the Y axis (Y axis=MPH) at each throttle position(X axis=TP) will firm up the shift at that TP) ( these values might differ depending on which gears you have)

trans tv press 1-2= x 0 0 0 0 0 52 400 600 1020
y 5 5 5 5 5 10 17 46 56

trans tv prss 2-3= x 0 0 0 28 52 252 400 600 1020
y -5 -5 -5 -5 0 8 8 27 42

-- How to get the tranny to shift later or sooner, under normal driving conditions (not wot)--


Trans Shift Schedules

If youve installed diferent gears then factory, this setting will be thrown off, and might cuase your tranny to shift much too soon. When i went from 327's to 373's my tranny shifting way to soon, so i had to make changes here
the Y axis represents MPH and the X axis represents TP( throttle presure) So to effectivly make your tranny shift later you would increase the MPH( Y axis) at whichever throttle position needed. If you just want to change the low speed driving shifts, then only increase the first 6 numbers for the MPH. I usually start increase 2 mph at a time, untill i have achieved the disired shift at that throttle postition.



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