Bolt on instant performance by upgrading or replacing your restrictive, cracked factory manifold with this BladeRunner port matched manifold. Designed to outflow the stock manifold by 12% for improved throttle response, the BladeRunner manifold has both the inlet and the outlet ports machined to match the factory ports for a smooth transition and optimal flow path. Constructed from heavy walled, ductile iron to resist warping and cracking, the BladeRunner will outlast OE and factory replacement manifolds.