Back in July i had taken my entire air intake system apart on my car to paint peices of it

And when i put it back together i installed a K&N high flow filter, but i forgot to install the lil snorkel inlet tube that goes from the Grill to the AIR box.
Now when the car went above 3K Rpm it sounded awsome but gas miliege suffered alot.

Scince then i have re-installed the snorkel thing and all is nominal.
Now my question to TN is: Can i modify the air box i.e. Make the small snorkel inlet hole bigger to let in as much air as possible without the use of the stock snorkel?
Cause id like to get the stock air system as less restrictive as possible and i think that 1-1/2" Tube is very restrictive.
The picture below is from a Big three install i did, But the snorkel im referring to is the orange thing in the picture: