XLPE Roto - molded Intake Tube The EVO2300 Evolution Air Intake System uses a custom designed and dyno - tuned, intake tube to produce huge power gains while retaining an OE quality fit. The specially tapered tube starts out at a huge 5 inches and slowly tapers down to 3.5 inches to ensure massive airflow at the turbo inlet. We have also incorporated our internal MegaRam (MR) technology for safe and effective power gains. Our intake tube also incorporates a custom CNC - Machined mounting flange that imitates the stock attachment method. This positive attachment method ensures that your intake remains securely attached to the turbo without fear of it slipping off like our competitor's rubber couplers.