View Single Post
Old 05-18-2011, 05:58 PM   #274 (permalink)
jran76
Base Member
 
Join Date: Nov 2009
Location: Plano, TX
Posts: 74
Drives: 09 G37S Sedan 6MT
Rep Power: 16
jran76 is on a distinguished road
Default

Quote:
Originally Posted by Nixlimited View Post
I assume the injectors in the left bank of cylinders will be pulsed according to the reading of MAF 1 and the injectors in the right bank of cylinders will be pulsed according to the reading of MAF 2. One of the drawbacks of 1 MAF is the assumption that air metered by the MAF is equally distributed to the different cylinders. I assume 2 MAFs helps mitigate this issue; however, as we have seen with this project, that does not hold true when the piping is changed. I hate MAFs altogether. Give me MAP metering any day!
The air from both intakes (and MAF's) all ends up in the same place. They are not divided inside the plenum/manifold, and the runners are in a row down the middle so they are pulling air from both intakes at the same time as it is mixed inside the plenum. The ECU just sees the air flow (voltage) from both MAF's and calculates the two together as the total amount of air going in. If each intake only went to one bank of (3) cylinders, the OP would have to re-do the piping to have somewhat even airflow to each side. Since the air is mixed inside the plenum, they are going to overcome the issue by allowing more airflow on one side than the other, and upgrading the MAF's to handle more airflow/voltage on that one side that has more airflow (really a band-aide for the uneven airflow, but it will work with the way our intake plenum and runners are setup).

Edit: The above is not correct. After looking at some pics and the service manual, it is split inside the manifold, and the ECU is looking at the MAF signals as Bank 1 and Bank 2.
__________________
2009 G37S Sedan-6MT: Advan / Volk / Tein / SPC / Invidia / Cobb / K&N

Last edited by jran76; 05-18-2011 at 07:15 PM.
jran76 is offline   Reply With Quote