DNA Motoring BOITCL+PPJETTA9918TBK Bolt-On Intercooler+Piping Kit [For 99-05 JETTA/GOLF GTI Mk4/A4 1.8L] High Performance Bar and Plate Turbo Racing Design Helps Reducing Engine Inlet Temperature; Increase 65% Air Flow comparing with other Standard Piping Allow More Horsepower at the Same Boost Level and Even More Power at the Higher Boost Level Direct Bolt-On Front-Mount Installation; Easy to Install Intercooler Size: 27.25"(L) X 5.75"(H) X 2.75"(W); Core Size: 21.5"(L) X 5.75"(H) X 2.75"(W); Inlet/Outlet: 2.5"/2.5"; 2" Piping Diameter with 2.5" Connective Piping