JLT Big Air Intake Kit 1999-2004 Lightning Average RWHP gains over stock is 15 to 20. Average RWHP gains over stock is 15 to 20. JLT intake tube is 4 1/4" ID roto molded plastic to resist engine heat to keep the intake air charge nice and cool. No tune NeededAlso fits 2002-2003 F150 Harley.