What is speed density STI?
Speed Density is a tuning method where the ECU uses information based on manifold pressure and temperature using the MAP sensor and an added IAT sensor to calculate how much air is coming into the engine.
What do I need to run speed density?
Speed density systems do their work first by measuring the temperature of the inlet air and then the manifold pressure via a manifold air pressure sensor, or MAP sensor. They then calculate a density of air with which the ECU can calculate how much fuel it needs.
Are WRX STIS fast?
The sprint to 60 mph takes 4.7 seconds, putting the R on par with the Focus RS, but one-tenth behind the WRX STI, and top speed sits equal with the STI at 155 mph….Is The Subaru WRX STI Better Than The Volkswagen Golf R?
| Subaru WRX STI | Volkswagen Golf R | |
|---|---|---|
| Engine | 2.5-Liter Flat-Four | 2.0-liter turbocharged four-cylinder |
What sensors does speed density use?
Speed density is the older but more sophisticated method of fuel delivery. The MAF is out, and this system relies on a combination of the MAP sensor and an intake air temperature sensor.
What is speed density fuel injection?
Speed density systems count on air pressure (as opposed to air flow) and engine speed (rpm) to compute fuel delivery. Many systems utilize a sensor in the exhaust system that allows the ECU to “check its math” and make any necessary adjustments.
Is speed density better than MAF?
Speed density offers an advantage in that it is better at handling high-revving engines than a MAF sensor is. Speed density is still preferred by many modified car enthusiasts, because tuning is simplified and because the wire within a MAF sensor can become an obstruction at very high power-levels.
Does speed density used O2 sensors?
Production-based Speed Density computers also utilize an oxygen (O2) sensor mounted in the exhaust tract. The computer looks at the air/fuel ratio from the O2 sensor and corrects the fuel delivery for any errors. Most Mopar fuel- injection systems have used Speed Density too.
How does Cobb speed density work in Subaru?
The COBB Speed Density feature is a powerful yet easy-to-use solution that integrates Speed Density tuning into the Subaru engine control unit (ECU) and can be used to entirely replace or work in conjunction with the existing factory mass airflow (MAF) sensor.
How is tuning SD done on a Subaru?
Tuning SD is achieved through manipulating a real-time tunable volumetric efficiency (VE) table. Because the VE table units represent actual VE, properly calibrated SD tunes can be used to compare VE across different cars with different mods, even if the SD airflow is drastically different.
What kind of PSI sensor does a 2008 STi have?
The 2008+ STi has a 3 bar MAP sensor so it can read up to about 28 psi and other Subarus can read up to about 24 psi. With SD we are using MAP for fueling so we can’t go close to those limits. An AEM 3.5 bar or AEM 5 bar sensor is recommended on most applications unless boost will be lower than the limits by a good margin.