How to tune your AP for your intake;
First off let me point out how important it is to have this done correctly. The cars ECU bases nearly all the important tables on your MAF readings. The MAF turns voltage readings into to a calculation of the amount of air entering the engine.
A hot wire mass airflow sensor determines the mass of air flowing into the engine’s air intake system. The theory of operation of the hot wire mass airflow sensor is similar to that of the hot wire anemometer (which determines air velocity). The Buick motor division (GM) was the first car company to use the hot wire sensor. This is achieved by heating a wire with an electric current that is suspended in the engine’s air stream, like a toaster wire. The wire's electrical resistance increases as the wire’s temperature increases, which limits electrical current flowing through the circuit. When air flows past the wire, the wire cools, decreasing its resistance, which in turn allows more current to flow through the circuit. As more current flows, the wire’s temperature increases until the resistance reaches equilibrium again. The amount of current required to maintain the wire’s temperature is directly proportional to the mass of air flowing past the wire. The integrated electronic circuit converts the measurement of current into a voltage signal which is sent to the ECU.
If air density increases due to pressure increase or temperature drop, but the air volume remains constant, the denser air will remove more heat from the wire indicating a higher mass airflow. Unlike the vane meter's paddle sensing element, the hot wire responds directly to air density. This sensor's capabilities are well suited to support the gasoline combustion process which fundamentally responds to air mass, not air volume.
(Stolen from WIKI)
Now with that explained we can move on to how this is used.
Calculated load; This is really a mathematical equation of the amount of fuel and air entering the combustion chamber. The higher the amount of fuel and air the higher the calculated load which equates to power. Now without getting to in depth on the math of it this is important because this value is what your car bases boost off of.
Say you have a load value of 265 in your table, depending on the ambient temps and barometric pressure your car may need 24-28 psi of boost to reach this load value. This is because colder air is denser than hot so there are more oxygen molecules per square inch to burn your fuel. This is why some of you will notice after your tuned using the stock system your boost will fluctuate with ambient temperatures.
So lets move on to preparing for the tuning part. You will need ATR (AccessTunerRace) and a laptop to run it. You can get ATR here by filling out the survey and entering the serial # in for your AP; http://accessecu.com/register/cobb.php
As of now it only works for 32bit XP and Vista computers but Cobb just released a 64bit version for AP manager and Updater so hopefully ATR won't be far behind. This is available through this page; http://accessecu.com/register/64bitbeta.php
Be sure to get the right one for your computer. To do this go to your “My Computer” icon right click à Properties à and under system type it will say 32 or 64 bit. Sorry Mac users nada support for you.
Once you have that loaded on to your computer get your AP ready because it will have you plug it in during the install to verify and select the correct drivers. (I have a feeling my PM box is about to fill with questions lol)
Next download the current (BETA) firmware for your AP, and a new map containing an intake that resembles the one you have. Pay close attention to the MAF housing size for selection.
Ok now your ready to start logging data for your tune! For this portion of tuning you DO NOT need a wideband. This will all be light throttle closed loop tuning so you won’t be experiencing any lean conditions that will harm your car. Beyond this step though you should not proceed with tuning without one. Also be aware that ATR software is only compatible with a select amount of wide bands.
Step 1;
Load your map on to the ECU and get your laptop situated and ready to log. Once the map is loaded start your car and connect the laptop to the OBD2 port. Start ATR and get your options set (It’s a good idea to read the help file before hand if you have not used ATR before). Once connected and still at idle CNTRL+F will bring up your options menu Note; you will get different options menus depeding on if your connected to the ECU configer both options menus. Select the parameters you wish to log and what you want to see on your dash board (This has to be done while connected to the ECU). For intake tuning you will need to log; LTFT, STFT, and MAF volt. Try not to log more than 12 items at a time because it will slow down how often it pulls them. CNTRL+L will connect you to the ECU, and CNTRL+B to bring up your dash board. (I forgot to tell you but add ECT (Engine coolant temp) to your dash board so you can view it here. If it is between 175 and 180 go ahead and shut the car down (Plus your computer if your using battery power).
Step 2;
Your car is warm, your new map is loaded, you have made sure that you can connect with ATR and you have selected all the correct parameters to log. Good now unhook the positive side of your battery so you can reset your ECU. This is to make sure that all save long term fuel trims are wiped clean from the memory so your logs aren’t contaminated for tuning. Once the positive terminal is disconnected hold your brake pedal down for about a minute then let the car sit for about 10 minutes. When this is done and you reconnect your battery your clock should say 1:00 and all your preset radio stations should be gone. If not disconnect again and add a few minutes.
Step 3;
Everything is reset now and clean so you can start your car, connect ATR (CNTRL+L) bring up your dashboard (CNTRL+B) and start logging (CNTRL+D). You will know your logging if you look down in the bottom right hand side of the screen it will say it in a small box there. Now you can start your drive using only light consistent throttle movement without getting into boost. TIP; (If you are familiar with ATR you can lower your load levels in the target tables to be sure you don’t get into boost.) Now get in about 10 – 20 minutes of cruising in various gears at low rpms making sure not to have any sudden throttle movements. This will cause a fuel enrichment you don’t want. When your cruise is done hit (CNTRL+D) again to stop logging and save the file.
First off let me point out how important it is to have this done correctly. The cars ECU bases nearly all the important tables on your MAF readings. The MAF turns voltage readings into to a calculation of the amount of air entering the engine.
A hot wire mass airflow sensor determines the mass of air flowing into the engine’s air intake system. The theory of operation of the hot wire mass airflow sensor is similar to that of the hot wire anemometer (which determines air velocity). The Buick motor division (GM) was the first car company to use the hot wire sensor. This is achieved by heating a wire with an electric current that is suspended in the engine’s air stream, like a toaster wire. The wire's electrical resistance increases as the wire’s temperature increases, which limits electrical current flowing through the circuit. When air flows past the wire, the wire cools, decreasing its resistance, which in turn allows more current to flow through the circuit. As more current flows, the wire’s temperature increases until the resistance reaches equilibrium again. The amount of current required to maintain the wire’s temperature is directly proportional to the mass of air flowing past the wire. The integrated electronic circuit converts the measurement of current into a voltage signal which is sent to the ECU.
If air density increases due to pressure increase or temperature drop, but the air volume remains constant, the denser air will remove more heat from the wire indicating a higher mass airflow. Unlike the vane meter's paddle sensing element, the hot wire responds directly to air density. This sensor's capabilities are well suited to support the gasoline combustion process which fundamentally responds to air mass, not air volume.
(Stolen from WIKI)
Now with that explained we can move on to how this is used.
Calculated load; This is really a mathematical equation of the amount of fuel and air entering the combustion chamber. The higher the amount of fuel and air the higher the calculated load which equates to power. Now without getting to in depth on the math of it this is important because this value is what your car bases boost off of.
Say you have a load value of 265 in your table, depending on the ambient temps and barometric pressure your car may need 24-28 psi of boost to reach this load value. This is because colder air is denser than hot so there are more oxygen molecules per square inch to burn your fuel. This is why some of you will notice after your tuned using the stock system your boost will fluctuate with ambient temperatures.
So lets move on to preparing for the tuning part. You will need ATR (AccessTunerRace) and a laptop to run it. You can get ATR here by filling out the survey and entering the serial # in for your AP; http://accessecu.com/register/cobb.php
As of now it only works for 32bit XP and Vista computers but Cobb just released a 64bit version for AP manager and Updater so hopefully ATR won't be far behind. This is available through this page; http://accessecu.com/register/64bitbeta.php
Be sure to get the right one for your computer. To do this go to your “My Computer” icon right click à Properties à and under system type it will say 32 or 64 bit. Sorry Mac users nada support for you.
Once you have that loaded on to your computer get your AP ready because it will have you plug it in during the install to verify and select the correct drivers. (I have a feeling my PM box is about to fill with questions lol)
Next download the current (BETA) firmware for your AP, and a new map containing an intake that resembles the one you have. Pay close attention to the MAF housing size for selection.
Ok now your ready to start logging data for your tune! For this portion of tuning you DO NOT need a wideband. This will all be light throttle closed loop tuning so you won’t be experiencing any lean conditions that will harm your car. Beyond this step though you should not proceed with tuning without one. Also be aware that ATR software is only compatible with a select amount of wide bands.
Step 1;
Load your map on to the ECU and get your laptop situated and ready to log. Once the map is loaded start your car and connect the laptop to the OBD2 port. Start ATR and get your options set (It’s a good idea to read the help file before hand if you have not used ATR before). Once connected and still at idle CNTRL+F will bring up your options menu Note; you will get different options menus depeding on if your connected to the ECU configer both options menus. Select the parameters you wish to log and what you want to see on your dash board (This has to be done while connected to the ECU). For intake tuning you will need to log; LTFT, STFT, and MAF volt. Try not to log more than 12 items at a time because it will slow down how often it pulls them. CNTRL+L will connect you to the ECU, and CNTRL+B to bring up your dash board. (I forgot to tell you but add ECT (Engine coolant temp) to your dash board so you can view it here. If it is between 175 and 180 go ahead and shut the car down (Plus your computer if your using battery power).
Step 2;
Your car is warm, your new map is loaded, you have made sure that you can connect with ATR and you have selected all the correct parameters to log. Good now unhook the positive side of your battery so you can reset your ECU. This is to make sure that all save long term fuel trims are wiped clean from the memory so your logs aren’t contaminated for tuning. Once the positive terminal is disconnected hold your brake pedal down for about a minute then let the car sit for about 10 minutes. When this is done and you reconnect your battery your clock should say 1:00 and all your preset radio stations should be gone. If not disconnect again and add a few minutes.
Step 3;
Everything is reset now and clean so you can start your car, connect ATR (CNTRL+L) bring up your dashboard (CNTRL+B) and start logging (CNTRL+D). You will know your logging if you look down in the bottom right hand side of the screen it will say it in a small box there. Now you can start your drive using only light consistent throttle movement without getting into boost. TIP; (If you are familiar with ATR you can lower your load levels in the target tables to be sure you don’t get into boost.) Now get in about 10 – 20 minutes of cruising in various gears at low rpms making sure not to have any sudden throttle movements. This will cause a fuel enrichment you don’t want. When your cruise is done hit (CNTRL+D) again to stop logging and save the file.
