I have a 94 F150 4x4 with the 5.8L. It has a K&N CAI, high voltage coil, 8.5mm plug wires and shorty headers. I currently run the single line two tandem OEM converters into a Flowmaster 40 series muffler and out as duals. I'd really like to see if I can pick up some power / fuel mileage and was wondering if going to a true dual exhaust without any Cats would be a benefit or a hindrance? I know there's two schools of thought on this with regards to maintaining some back pressure, especially on a virtually stock motor. Any one have any real experience?

 

I'd ditch the K&N intake to minimize the amount of dirt gettin' through it into the motor. Especially "CAI" that usually just pulls in heated engine compartment air through a coolant heated throttle body.

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