How to tune a car, step by step.

[niterydr]

Step 1)

Make sure your vehicle is in proper working condition. Fresh spark plugs with a good gap (and proper heat range). Proper octane fuel for the power level. No boost leaks (especially on a MAS based system), proper supporting mods for the intended power levels.
Do a boost leak test BEFORE you attempt to tune on a MAS based system.
In case you didn't catch that....
CHECK YOUR CAR OVER BEFORE YOU TRY TO TUNE IT. Mechanical problems will fester and destroy your tuning budget.

Now we all know here that an engine is just a giant air pump. Three things are required to make power. Oxygen, Octane, and Ignition. Compression comes naturally due to how the engine should be working, if you don't have compression, see step #1. With more oxygen, more octane is required. When they balance out correctly you get power. Ignition is used to control the burn and make sure you have equal burn across the cylinder. This isn't rocket science guys and the factory was pretty good for optimum ignition timing for a XX amount of air and XX amount of fuel molecules (aka power level), and the factories math holds fairly true for quite some power over stock.


Step 2) What fueling system are you using? MAS or Speed Density? (These are the two options everyone here should be using).

This post I will cover MAS based systems, the next post I will get into speed density and standalones.
Step 2a)
MAS: Mass Airflow Sensor
How a MAS sensor works is purely math. On most systems there is a wire there that physically counts air molecules that hit it. The sensor is programmed with its overall flow area and knows that xx air molecules over xx sq inches= xx flow rate. Until you reach the flow maximum of a sensor, this formula will remain the same. Now it isn't exponential, it is more of a curve that gradually tapers out at a certain HZ value, for arguments sake, lets call it 3000hz.

Now at idle most cars are low on airflow, typically between 10-100hz. Because of this you only need so many fuel molecules to maintain the 14.7molecules of air to: 1 molecule of fuel ratio.

Now there are two types of MAS sensors, hot wire and hot filament. The pretty much function the same.
The sensors in our cars are called Karmen Vortex MAS sensors. They are a bit more advanced as they measure pressure waves/turbulence changes. More airflow=more turbulence. Instead of a heated element/wire catching air molecules the sensor measures waves using a LED, mirror, and photo receptor. Pretty much it uses these together to measure fluctuations in pressure. I would concern myself with how the function differently from a MAS sensor because the principal is pretty much the same and they tune fairly similar.

Important MAF system facts:
A)If you decide to mess/move your MAS sensor remember a few things.
1)It is designed in a DRAW THRU environment only. I am sure people have put them in blow-thru (in fact I've seen it like that on a supercharged 3000gt, I won't name the kit as this isn't the purpose of this thread) but Mitsubishi designed it to pull thru.
2) MAS sensors are very sensitive to turbulence. Sharp bends before or after the MAS wires/pressure chambers will cause falsified readings. MAS sensor will double/triple/quadruple count air molecules and that will play hell for your fueling maps.
B) It is a calculated fuel system. This means if you tune with boost leaks, you are shooting yourself in the foot! XXXhertz measured by the MAS sensor should mean XXXhertz in the throttle body. When you loose air, your ecu is still expecting the air to be there and will inject the appropriate amount of fuel (pending you have enough injector left), this means you will run rich. On another side note, the factory knows the compressor maps for your compressor wheels. I knows where the efficiency island is and where the engine is running from the factory. They know how efficient the intercooler are. They understand what the intake air temperatures are going to be at the inlet valve under most conditions. This is why the karmen vortex meter has a intake air temperature sensor at the MAS as it uses this information to scale the fuel/timing maps slightly. When you change turbochargers, you change efficiency and need to tune appropriately for it. Intercooler changes changes can also throw off how a vehicle runs. Now most td04 setups are fairly close at lower boost levels (and mostly the same in cruising obviously), as long as you size your injectors properly, you will be fine.



Why can't I run huge injectors on my MAS system?
1)Why bother? Again, you can use math to determine how much fuel is required for xxxawhp. Size your injectors correctly and you will save headaches. Since you are using a piggyback, all you are able to do (most of the time) is to scale your larger injectors to match your desired Air/Fuel ratio on the factory maps. If your injectors are 20% larger than stock, then odds are you will need to remove roughly 20% fuel at WOT/open loop fueling to make it roughly the same.

I guess I should get into how an injector works. Injectors are rated in flow rate and duty cycle. Most modern injectors are not recommended to run over 90% duty cycle, I shoot for 85% duty cycle to be safe. Duty cycle is defined as how many Milliseconds the injector is open for.[Duty cycle= (pulsewidth)/ (total time between ignition events)] You must remember that injectors are "charged" like a coil and there is a specific amount of dead time required for the injector to open.

Also on another side note, injectors are linear in flow until under 1ms of flow. There is a certain slope aka flow rate an injector follows. XX increase in psi = xx increase in flow increase. Now at very low duty cycles the slope is actually higher (aka your injector is larger) because the injector rams open so quickly it creates a vacuum on the other side of the pintel and fuel is forced out quicker than normal. Typically injectors are slightly larger at very low pulse widths compared to normal operations, figure a few percentage. See below. Time is MS pulse width, the breakpoint is where the injector is controlled smoothly/predictably (you can actually calculate both slopes using dead-time, injector flow rates, injector type, voltage @ the fuel injector).
Offset=dead time, aka the time it take to charge the coil inside of the injector to fire it open.


not my picture but one I found on google that is pretty good!
Why does this matter? Well remember that you need the least amount of fuel at idle. So good luck getting your 880cc injectors to idle with a MAS setup without seriously tweaking the system.

Finally the last bit on injectors. Injector drivers play a huge role on how much of that injector you are actually getting (see dead time). If the drivers aren't very good/universal/sloppy (aka AEM), you will need to compensate for this and run a slightly larger injector. We have found out that +100cc injector will usually put you roughly to what you should calculate using a factory ECU. So for all of you piggyback guys, follow the advise of the old school senior members on here, use the math. The factory ecu is VERY GOOD at controlling the stock style injectors. Also remember that there is also a small amount of close deadtime but it is nothing compared to opening deadtime. Lower battery voltage also increases injector deadtime as it takes longer to charge.

Now that we have some basics covered, lets get into it.

Step 2b) Speed Density systems
FACTS:
Speed density tuning is not as accurate as MAS based systems.
Speed density tuning supports more power capabilities than MAS based systems.

I figured we would start with that. Since we are merely calculating air density, instead of measuring, air density, we can not get it as perfect as a MAS based system. Fortunately most speed density cars are for more power than stock and most owners don't care about 100% perfect reliability in all weather conditions. Sacrifices are made for power potential.

How a speed density system calculates required fuel is different from a MAS based system. The system relies heavily on a few items.
1) an accurate MAP (Manifold Absolute Pressure) sensor
2) an accurate IAT (Intake Air Temperature) sensor
3) an accurate engine rpm pickup
4) known engine VE (Volumetric Efficiency)

The first 3 are really easy to work with. Fortunally for this community AEM (for those so inclined) as a pretty decent "base map" for number 4. I believe Grayson as posted a few great basemaps for the e-manage crowd. I know Trevor has also posted some great MAP ECU data files as well.

Now a Map sensor needs to be mounted in a location where it will get a CLEAN pressure signal and vacuum signal.

AIT sensors need to be mounted as close to valve inlet air temperatures as possible. I usually recommend the "y" pipe or upper intercooler pipe before the throttle body.


Some helpful tips:
The neat thing about speed density tuning is it is very fast to tune, much faster than MAS based systems. If you use features like "boost comp tuning" in the AEM EMS, you can get fueling maps dialed in pretty good/perfect in under 2 hours.
Your fuel demand should follow your torque curve, which should follow your engine VE. Does that make sense? As RPM goes up, fueling demands increase until peak torque is obtained (assuming airflow numbers stay the same, aka boost pressure). As you pass peak torque your engine VE will decrease and thus your demand for fuel while obtaining the same A/F ratio.

continued here:How to tune a car, step by step.

[niterydr]

Lets talk about commonly used automotive terms.

AFR- Air/Fuel Ratio. This is the Amount of Air molecules divided by the amount of fuel molecules.
AIT- Air Intake Temperature Sensor Also called an IAT sensor
CTS- Coolant Temperature Sensor
CMP- Camshaft Position Sensor
CKP- Crankshaft Position Sensor
Lambda- Lambda is the preferred method of measuring air/fuel ratio as it is more universal. Lambda of 1.0:1 is stoic for any fuel type, and it just scales accordingly. Gasoline Stoic is 14.7, while methanol is approx 6.5:1 ratio for that "perfect burn". Most vehicles make target peak torque around .85 lambda (ones that don't require fuel for thermal management, turbocharged vehicles like it around .72-.78 on gasoline). Lambda is easy to fine, take your actual AFR and divide it by your Stoic AFR, that's your lambda!
LTFT- Long Term Fuel Trims
ICS- Idle Control Solenoid. Steppers or pulse style usually. Our cars uses a steppers style solenoid for idle control.
MAS- Mass Airflow Sensor
MAP- Manifold Absolute Pressure Sensor
O2- Oxygen Sensor, available in narrowband and wideband.
STFT- Short Term Fuel Trims
TPS- Throttle Position Sensor, on our vehicles there is a single 0-5v signal. 0 being closed, 5v being wot. 4.8v and + is acceptable

Closed loop- Preset fuel control, usually on a percentage of available adjustment. Pretty much this is idle and part throttle/driving conditions where engine stability is predicted and doesn't change rapidly. Most OEM's have around 15% available for fuel trimming. This is where narrowband oxygen sensors prevail and are important to use.

Open loop- Commanded air/fuel ratio based on a VE chart of the engine. All WOT fueling is done in "open loop". The ecu isn't checking and double checking airflow readings/rpm/vacuum and is just going to your VE table, grabbing a cell, and plugging that much fuel into the engine.

Narrowband Oxygen Sensor- These are factory 02 sensors and found in virtually all modern production vehicles.
Wikipedia actually has a good write-up on oxygen sensors:
http://en.wikipedia.org/wiki/Oxygen_sensor
They emit a 0-1v signal. They are highly accurate around stoichiometric air/fuel ratio and help keep a car at that afr. They achieve this accuracy via "switching" see below.

Above is a great illustration from a great wideband manufacture, PLX Devices.

As you can see from above, there is a narrow range of voltage that is emitted from the oxygen sensor that lets the ecu know which side of stoic the vehicle is running (Most oems consider stoic 14.5-15.3afr) How narrowband/closed loop o2 feedback works is the ecu will poke or "trim" positive or negative (according to what the original reading was) and try to keep the vehicle on that exact switching point...this is called your STFT (short term fuel trim). Most OEM's shoot for a 3% accuracy and window. They will "trim" lower than that, but they won't be saved into LTFT's most likely.

LTFT's are stored trims the ecu has "learned". This is how oem cars can seem to run fine with larger injectors at idle/cruise, the ecu is constantly learning/adapting. The OEM's built this in to deal with declining/failing injectors, engines, sensors, and climate changes. Very important for OEM's to have for emissions controls as well. As vehicles age, systems weaken and they need to run similar to how they ran when they were new, for both performance and emissions compliance.

Wideband Oxygen Sensors- These are sensors that are based on a 0-5v scale and most commonly spit out a liniar signal. 0v being rich 5v being lean. They usually read/measure from around 9 afr to 22 afr. This is mostly based in the controller and how it is configured.
The beauty of these is how spread out the signal is. With 5volts to use, a .100 change in voltage makes a change in actual afr ratio on the "point" scale (14.7:1 vs 14.5:1, etc..).

[niterydr]

A little bit on intercooler cores:
Tube and Fin cores allow air to pass through them easier. This allows for a cooler charge to make it to the radiator (in a fmic application) which will help aid in the prevention of overheating. The reason they do so, is due to design. Where-in a bar and plate (and a plate-tube and fin core) are more squarish, the tube and fin core almost 'points' outwards, thus piercing the air easier.
A tube and fin core makes a 'V' while the bar and plate make an '[]' shape and the plate-tube and fin makes a 'W' shape. Therefore they rank in order.
1) tube and fin
2) plate-tube and fin
3) bar and plate.
This is in the c/d category as well as cooling running engine factor. Granted how the nose of the car is shaped will change the efficiency and mounting method of the intercooler and radiator greatly. The more direct of a path airflow has to the intercooler, the greater the efficiency. To thick of a core can sometimes 'trap' air from getting through it, as well as to drastic of a mounting angle. These problems can be overcome by allowing for more surface area in a trade off of thickness.

Next section...how the air moves through the intercooler.

The faster the air can get through the intercooler core the better. This pretty much sums up 'pressure drop'. When the air has a hard time dividing up through the runners, pressure drop goes up 10 fold. Plate-tube and fin cores are the best in this situation. They allow the air only once choice, that is to split and enter the core. This is usually based on the manfacture, but mostly the plate-tube and fine cores result in the least amount of pressure drop. Second in this category is the bar and plate. They sometimes make the air do a 90 degee split then enter the tubes, but it usually works out. Lastly the tube and fins are the worst. Air usually has to do a 180 when it doesn't grab a tube right away, bounce back against the endtank, and go back at the tube again. Not the greatest idea when it domes to pressure drop. Manafacture methods can sway these results on way of the other, but this is in general.
So.. when it comes to pressure drop.. Plate-tube and fin #1, followed by bar and plate, then tube and fin in a distant third.

Next we actually talk about cooling.

Bar and plate are by far the best at cooling an air charge. They displace more heat then the other two examples widly available. A few changes within the manafacture method will change the outcome, but overall bar and plate is better at getting rid of heat. A properly made tube and fin core can beat out a plate-tube and fin core as well as a bar and plate, but overall most manafactures don't construct them correctly and when they are, the usually cost quite a bit.

Actually I am getting tired of posting so i'll sum it up.
There is no better one. It really comes down to a multitude of options. Bar and plate cores are good overall if constructed properly. Granted they are the most prone to leaks, if the endtanks aren't attached correctly, but overall they are better. Plate-tube and fins are also awesome cores. Tube and fins can be the best, but usually aren't due to the expense of making them correctly.
I didn't even get into the other very very important aspects of intercooling, like endtank design, fin design and shape (louved vs straight...spacing, amount of fins etc)..piping sizes, coupler use..bend radius's..etc.
Most of the time the only hamper on awesome intercooling is money. That is of course if you don't go insane and use to large of an intercooler.
That being said, a few manafactures out there stand out. Also try to find out of the 'pressure drop' advertised is static or dynamic. Static is best defined as 'flow bench aquired' pressure drop numbers where dynamic actually is closer to real life and takes into effect the entire design of the intercooler, from basis (tube and fin vs bar and plate), to fins..etc..
That being said, here are a few manafactures and what I think of them..
Spearco intecoolers.
They are widely available and are actually good stuff. They have realitivly low pressure drop numbers, have a wide range of cores available and in general are a great option.
Btw they are a high efficent pierce fine design on the inside and out. This results in awesome efficiency in the air charge department as well as low pressure drop.
PTE use a bar and plate style core. they are widely available, very economic, and when paired with good endtanks can flow very well. There core choices aren't as vast as spearco, but they do hold there own.
Tube and Fin cores allow air to pass through them easier. This allows for a cooler charge to make it to the radiator (in a FMIC application) which will help aid in the prevention of overheating. The reason they do so, is due to design. Where-in a bar and plate (and a plate-tube and fin core) are more squarish, the tube and fin core almost 'points' outwards, thus piercing the air easier.
A tube and fin core makes a 'V' while the bar and plate make an '[]' shape and the plate-tube and fin makes a 'W' shape. Therefore they rank in order.
1) tube and fin
2) plate-tube and fin
3) bar and plate.
This is in the c/d category as well as cooling running engine factor. Granted how the nose of the car is shaped will change the efficiency and mounting method of the intercooler and radiator greatly. The more direct of a path airflow has to the intercooler, the greater the efficiency. To thick of a core can sometimes 'trap' air from getting through it, as well as to drastic of a mounting angle. These problems can be overcome by allowing for more surface area in a trade off of thickness.

Next section...how the air moves through the intercooler.

The faster the air can get through the intercooler core the better. This pretty much sums up 'pressure drop'. When the air has a hard time dividing up through the runners, pressure drop goes up 10 fold. Plate-tube and fin cores are the best in this situation. They allow the air only once choice, that is to split and enter the core. This is usually based on the manufacture, but mostly the plate-tube and fine cores result in the least amount of pressure drop. Second in this category is the bar and plate. They sometimes make the air do a 90 degree split then enter the tubes, but it usually works out. Lastly the tube and fins are the worst. Air usually has to do a 180 when it doesn't grab a tube right away, bounce back against the endtank, and go back at the tube again. Not the greatest idea when it domes to pressure drop. Manufacture methods can sway these results on way of the other, but this is in general.
So.. when it comes to pressure drop.. Plate-tube and fin #1, followed by bar and plate, then tube and fin in a distant third.

Next we actually talk about cooling.

Bar and plate are by far the best at cooling an air charge. They displace more heat then the other two examples widely available. A few changes within the manufacture method will change the outcome, but overall bar and plate is better at getting rid of heat. A properly made tube and fin core can beat out a plate-tube and fin core as well as a bar and plate, but overall most manufactures don't construct them correctly and when they are, the usually cost quite a bit.

Actually I am getting tired of posting so I'll sum it up.
There is no better one. It really comes down to a multitude of options. Bar and plate cores are good overall if constructed properly. Granted they are the most prone to leaks, if the endtanks aren't attached correctly, but overall they are better. Plate-tube and fins are also awesome cores. Tube and fins can be the best, but usually aren't due to the expense of making them correctly.
I didn't even get into the other very very important aspects of intercooling, like endtank design, fin design and shape (louved vs straight...spacing, amount of fins etc)..piping sizes, coupler use..bend radius's..etc.
Most of the time the only hamper on awesome intercooling is money. That is of course if you don't go insane and use to large of an intercooler.
That being said, a few manufactures out there stand out. Also try to find out of the 'pressure drop' advertised is static or dynamic. Static is best defined as 'flow bench acquired' pressure drop numbers where dynamic actually is closer to real life and takes into effect the entire design of the intercooler, from basis (tube and fin vs bar and plate), to fins..etc..
That being said, here are a few manufactures and what I think of them..
Spearco intercoolers.
They are widely available and are actually good stuff. They have realitivly low pressure drop numbers, have a wide range of cores available and in general are a great option.
Btw they are a high efficient pierce fine design on the inside and out. This results in awesome efficiency in the air charge department as well as low pressure drop.
PTE use a bar and plate style core. they are widely available, very economic, and when paired with good endtanks can flow very well. There core choices aren't as vast as spearco, but they do hold there own.
Those are a few of the companies I have done research into, google does wonders, so does being on A LOT of boards and having 7+ years into the industry.
other companies worth mentioning:
ARE cooling- aluminum radiator and engineering. Australia based company. From what I have gathered, have awesome intercooling making functions but aren't the most economical choice. They can pretty much custom make any core you need, and are a good choice for the 'budgetless' project.
Bell Intercooling-Great bar and plate intercoolers. Dense turbulators.

[niterydr]

Steps 1-2 are completed? Good, lets get started.

Step 3)

The most difficult time for any engine is idle. An engine LOVES WOT. I seriously spend 1/4 the time on WOT power compared to the rest of tuning (especially with my dyno). A rule of thumb is if you can't get the car to free rev in the parking lot, it is not ready for dyno time. If it can not sustain a stoichiometric a/f ratio around 2000rpm, you are not ready for dyno time. Now since this is MAS based systems specific to 3000gt ecu's, most of you should run okay and wouldn't worry about this portion of it.

A few key points to remember.
1) Fuel is used for THERMO MANAGEMENT. Stoichiometric a/f ratio for gasoline is 14.65:1. That is the chemical formula (okay I lied, tuning is mostly math, some physics, and some chemistry...sue me) for a perfect ratio with nothing left over for fuel and air molecules. [(14.68)air+C8H18=CO2+H20 +NOx]
2 Ideal power A/F ratio is 12.6:1-13.2:1. This is when you have the most power for the least amount of fuel consumption. Unfortunately since we use fuel as a means of thermal management we need to error richer than this for 92 octane. This is since our intake air temperatures are most likely higher than ambient air temperatures at the air filter AND since our fuel isn't very consistent compared to higher blends of octane (aka more prone to pinging due to lower octane).
Most vehicles I setup like this:
14.7 for idle, cruising, and most transient rpm throttle points.
13.5-13.0 (rpm dependent) around 0" of vacuum or 0psi as this is roughly the best a/f ratio for peak power with the least amount of fuel consumption (remember kiddies the name of the game is responsible tuning, lets not deplete all of our available fossil fuels in 1 pass down the drag strip, let alone foul our plugs and wash out our cylinder bores) Also remember the name of the game is smooth. Make it taper in smoothly, vehicles do not like air/fuel ratios that behave like a "switch" (14.7 BAM 11.2, not a good idea).

Most sidemount intercooler vehicles running substantial boost on pump gasoline (14psi-20psi) I error towards the side of safety and target between 10.7-11.3 a/f ratio under peak load/power. I let the car tell me what it likes, but 99.992% of the time end up in that range. Remember the fact that most OEM's shoot for 3% accuracy using narrowband oxygen sensor inputs, so don't kill yourself on this one.
Cars that have better intercooling I tend to run a bit leaner as I don't need as much (drum roll please) thermal management. Most FMIC cars are 11.0-11.6 a/f ratio on pump gasoline. Again, you use fuel for thermal management. A few decimal points will help starve off the knock threshold, especially if you are higher than stock timing.
3) Timing:
Please for the love of god, log your car. I don't need a logger on most 3000gt's anymore with piggybacks, but we have done more 3000gt's to count and my dyno logs torque actively . I know there is an factory timing value chart posted somewhere here on 3si or out there on wikipedia land, so I won't reference that, but you should be close to that.
Idle timing:
Usually 10-18, use only as much timing as you need. Idle is all about torque management You want enough timing to have have the car maintain a steady idle with minimal IAC motor input.
Most of you piggyback guys won't have much control over this (unless you globally scale your injectors incorrectly).
Cruise timing:
Most vehicles cruise with around 25-35degrees advance. As load goes up, generally timing decreases, as rpm goes up, generally timing increases.
Power timing:
Timing should ramp up with rpm except under most setups it is perfectly normal to have it dip under torque peak. As your engine reaches peak VE you will need less timing advance to obtain the same torque values. Timing is used to well "time" when you want that spark event to happen. Timing is dependant upon cylinder air temperatures, cylinder bore size, combustion chamber shape, octane, and rpm...that's it. Most 3000gt's tend to stay in double digits under peak power/higher boost on pump gasoline (less than 20psi). I would say 10-15 degees is safe. I know the factory map adds a bit of timing up top as the 9b turbochargers fall off boost at high rpm. To compensate with this lack of airflow, the factory increases cylinder pressure by timing. Most td04 cars follow the same trends (boost fad slightly), but I would highly recommend to keep your timing under 20 (actual).

Now remember they are just numbers that are being interpreted by a logger. AEM numbers and pocket logger "timing" values are not really interchangeable as each reads timing and calculates timing values differently.

*Now on race gasoline (especially 119 VP Fuels C-16) you can hit MBT LONG before detonating/knocking. This is a safe fuel to tune on, but requires a completely different gamplan. Target air/fuel ratios are leaner (read: more stable and more octane), and timing needed to keep it from miss-firing (not knocking, they look the same but are very different).

Wrapping up about wot tuning:
The most important things to remember about tuning WOT:
1)No sharp peaks. Your torque curve should rise smoothly and taper off smoothly. If it doesn't ask yourself why.
Is your boost fluctuating? Is there a mechanical problem? Are you knocking? Are you near a knock threshold and need to leave some room on the table?
Horsepower is a mathematical relationship of torque over rpm. By knowing your horsepower you know how efficient your engine/tune is at that RPM point. ((Torque x RPM)divided by 5252=horsepower)
2)Your air/fuel ratio should remain flat. Pending what type of wideband sensors you shouldn't see much fluctuation. If you have a point where it suddenly goes lean and then back to commanded afr (say at 5000rpm you are 11.0a/f ratio, then at 5200rpm you jump to 11.6 a/f ratio and then at 5400 its back to 11.0 a/f ratio) you have a problem. Most likely that is an cylinder misfire, but it could be knock. Start buy pulling timing (safety versus sorry) or boost, see if it cleans up. Do it a few times (assuming you started aggressive on your wot tuning) and if it doesn't fix it, go the other way.
3)Since you are logging, you should have minimal knock count. If it does "knock" what does the car do? Does it make sense it is knocking? Does it ramp up smoothly, or spike?
Sometimes noise can be interpreted as knock, especially with modified engines.

Throttle tip in fueling should be handled well enough from the factory, same with decel (factory ecu should take care of all that). Your 02 sensors should keep you within check at part throttle conditions once you dial in your injectors, and timing shouldn't change much expect for peak power levels compared to factory.

My logical form of tuning:
1)Car mechanical sound
2)Make it start
3)Keep it running at 2000-3000rpm
4)Make it idle
5)Make it move under its own power
6)Part throttle tuning
7)WOT fuel/timing
8)Trims and corrections.

Questions/Comments/Concerns?

Did I miss anything on this?

[casperlynn]

Josh, I am extremely impressed with your knowledge base.....hard to believe you are only 25!!! On top of that, you authored most of this post during a lunch break LOL!

I knew you had it in you, based on the advice/solutions you were throwing in my direction.

I know your intention was not to impress, but to educate..........you have done both dude!

BTW, my hot wired MAF is setup to "draw thru" so I know you were not talking about me LOL!

[GTO Assassin]

Great thread Josh. I wish you'd put as much thought into that holiday in Oz we have spoken about.

Scotty

[happyGilmore]

Now THAT'S some good reading, thanks man for takin the time to put that up...... + propz as well man.

[niterydr]

That should get a good jump going. I am fine turning this into a Q&A tuning/theory/engine question thread.

[niterydr]

Originally Posted by GTO Assassin

Great thread Josh. I wish you'd put as much thought into that holiday in Oz we have spoken about.

Scotty

I told me, tell me when to come down and I will fly in.

[spfan]

Originally Posted by niterydr

Duty cycle is defined as how many Milliseconds the injector is open for.

bravo. it's good to have all that info in one, very readable, thread.

only thing: i know this is nitpicking, but i just don't want a new guy to tuning reading this and getting confused. but duty cycle is actually the percentage of the time the injector is open in relation to the amount of time it can be open, correct? ie: at 100% duty cycle, the injector is open all the time. at 5% duty cycle, it is open 5% of the time. the rest it is closed. what you defined is actually the pulse width, correct? please correct me if i'm wrong.

but yeah,