DOC Race Nissan KA24DE Topmount manifold. Available with a MVS or MVR wastegate flange is for the more extreme setup looking for the potential limit of the vehicles engine. This manifold has seen well over 1000hp and is designed for peak-power situations. The DOC Topmount manifold can still be used for streetable vehicles, but is solely designed to make maximum horsepower and allow you to fit much larger frame turbos then our traditional ramhorn. D.O.C. still applies our elaborate porting process to complement maximum flow within ALL of our manifolds.