Edelbrock part #2506 Performer RPM Q-Jet marine intake manifold is designed for 1987-95 262-400 c.i.d. Chevy V8's for spread-bore (Q-Jet) or square-bore carbs. The Edelbrock Performer RPM Q-Jet #2506 intake manifold is designed specifically for demanding marine applications and delivers maximum power and a broad torque curve for high-performance marine. Delivers maximum power and a broad torque curve for high-performance marine. Carb pad will accept square-bore carbs without adapters. The Performer RPM Q-Jet marine intake manifold features brass lined front water crossover and brass flange inserts to cover the rear water openings.