Caliber SRT-4 owners – difference between Mopar stage 1 and Aem FIC packages.
We’ve gotten a good amount of questions from 08-09 Caliber SRT-4 owners asking us what the difference is between the Mopar stage 1 upgrade package and the AEM FIC.
The difference boils down to what your ultimate goal power wise.
If your happy with 320-330 horsepower at the engine, and a maximum of 15 psi, then the Mopar stage 1 kit is a great kit that improves throttle response and increases boost and power.
If you want more than 320-330 horsepower, and more than 15 psi of boost, then youll have to move to a AEM FIC kit. Why ? Well, it has to do with the PCM and the drive by wire system. The pcm will try to regulate boost level to limit torque steer and maintain smooth drivability. Therefore, if you are giving 100% throttle with the gas pedal, and you go over 15 psi, (or any boost level that the PCM is programmed to not allow the engine to exceed) then the pcm will cut back on the throttle to regulate the boost pressure.
Example: You have a boost controller on your 08 Caliber SRT-4, and want to do 18 psi. As soon as you floor the car, and are giving 100% throttle and exceed say 15 psi, the pcm will cut the throttle back to 60-70% to regulate the boost level to 15 psi.
The way to bypass this from happening, is to limit the voltage from the map sensor going to the pcm. The AEM FIC will do that for you, and then you can increase the boost level in your car to whatever you desire because the pcm thinks that your running at say 14 psi. The major problem with you running say, 20 psi, when the pcm is seeing 14 psi, is that the pcm will only deliver 14 psi worth of fuel, therefore making the car run excessively lean. The other major benefit of the FIC is that it will control fuel, so you can use the FIC to deliver extra fuel to make up for the pcm not putting out enough fuel.
Wiring up the FIC involves quite a bit of work. The FIC has MAP sensor inputs, and output (to modify the map sensor voltage), the FIC has input and outputs for the injector wiring, an more.
After the FIC is wired up, youll need to then use a laptop to program the FIC for the fuel curve as well.
So, as you can see, there is quite a bit of work involved. However, there is also QUITE A bit of power that can be made with the FIC as well!
More information on the AEM FIC here:
More information on the Caliber Mopar Stage 1 kit here: