Hey fellas. Since I updated to the EF manifold/air box in my EA I have noticed that the EF box has a noticeable restriction on performance.
If I run a straight pipe, with no box or filter, I notice a very decent torque and power increase.
At this stage the best performance I get out of the box is by having a 4" cut out in the bottom of the box taking in cold air, and leaving the original hole open as well. However, I still have a standard filter in it, and this is probably responsible for the remaining noticeable power loss.
I will be replacing the tapered extension with a 3.5" pipe to match the rest of the system, this might help a little.
IMO, the standard box needs work.
CAUTION: Slippery When BOOSTING!