Quote:
| Originally Posted by DustenT Now I'm confused, someone on the .net list said they were 19 lbs/hr. What is the advantage of the "air shrowded" injectors? On NickG's upgrade, the replacement injectors don't use the shrowd.
What the heck is LTFT's and STFT's? Excuse my ignorance, I can't fit anymore acronyms in my brain!!! |
I am not sure about the injector flow rating it was just a number that I reacall. As far as I know air shrowded in jector assist with the CARB/SMOG qualifications. It bypasses air from the throttle body so that the engine can idle. It works along with the ICV (Idle Control Valve).
As for STFT & LTFT.
STFT = Short Term Fuel Trim
LTFT= Long Term Fuel Trim
The LTFT and STFT assist with the way the ECU runs the car. While the car is being driven at <WOT the car is running in what is called closed loop, where the ECU tried to keep the Air/Fuel ratio at 14.7. Optimum for power and fuel economy. When the car goes >=WOT the car is in what is called open loop and runs off a predetermined fuel map.
If you add larger injectors the car will be running rich when it should be running 14.7, and the ECU will got to the fuel map look up table calculate a leaner value and replace the old value in the table there for making the car run at 14.7 with the bigger injector. With the ECU leaning the LTFT and STFT when you go WOT in turn you will run leaner as well.
-Chad