Standard bore road LCB (1-3/4"id) that has an enlarged and reshaped middle pipe which creates a type of vortex, simulating a pulsing effect similar to the outside two pipes,thus producing an improved BHP,Torque and power curve.Ideal for very hot small bore engines or high performance 1275s, and for street 1380s. This best quality production manifold is available from Minispares. This Long Center Branch design has been proven to be the best all-around for our 5 port cylinder heads in conjunction with top mini racing engineers who have won major championships. Bore diameter being the only other variable. Maniflow stage II LCB.