FAST LSXR intake manifold runners will restore proper airflow to your intake for the performance you crave. They are available in three sizes: Standard Street, High HP, or Race versions. FAST LSXR intake manifolds are designed to give you the ability to remove individual runners from the manifold for modification. FAST LSXR runners are yet another reason the FAST LSXR intake runners are the choice for LS3/L99/L76 engines.