Lower IC Pipe Set for 20g, Garrett and Other Downflow Turbos The Lower Pipes are 2 1/4in dia. mandrel bent steel tubing except for the compressor outlet elbow which is 2inat the compressor. These fit the Super Big Side mount or your stock side mount IC. Includes all stainless steel hose clamps & couplings. D2 model is expanded to 2 1/2in at the IC end. Part Numbers: LIP-2gD