Exhaust Coupler Choice Of Size
2.5" waterbox to chamber
3.5" RRP chamber to manifold
3.75" Powerfactor chamber to manifold
4" B Pipe chamber to manifold
our above chart is for reference only some manufacturers make slight modifications to their products from time to time which affects the coupler diameter all measurements are INSIDE DIAMETER.
all couplers are 3" long and 4 ply silicone , black in color