These manifolds have provisions for mounting the stock MAP sensor directly to the manifold and are primarily designed for Harley-Davidson Twin Cam 88 engines
Manifolds may also be used on engines for 84-99 Big Twins which require a MAP sensor, such as S&S engines equipped with the S&S Intelligent Spark Technology (IST) ignition
Available in 1-7/8 and 2-1/16
Size 5.550 Evolution  4.937 Twin Cam 88
Cnlinder Length 410 Evolution /Twin Cam 88