I have a 1998 RV on a Chev chasis with a 454 engine.  Can I get better
gas milage and/or power from this engine by increasing the size of the
air intake?
Is there any after market products out there that will help?

I'm driving a 2000 GMC 1-ton with a 7.4 liter engine and recently took it into a
shop because there was a gasoline smell coming from the exhaust.
They hooked up a computer and said the only code that came back bad was an O2
sensor so they replaced that and told me it was fixed.