USP Marine Tuning MAX+ Forced Air Duct For Mercury V8 Engine Family

Description

The USP Marine MAX+ Forced Air Duct is engineered specifically for Mercury V8 engines to solve a well-known power-robbing problem: the "station wagon effect." This happens when exhaust fumes get pulled back into the engine intake through the rear of the cowling at speed — causing power loss, reduced top-end performance, and increased fuel consumption. The MAX+ duct channels clean, high-pressure ram air from the top of the cowling directly into the intake, pushing exhaust gases away where they belong.

Designed with the Mercury 500R and 450R in mind — the performance leaders of the V8 family — this duct maximizes airflow to match the engine's demands. The 300R and all V8 mainline models benefit equally from the upgrade.

Built in the USA. Built from Fiberglass.

The USP Marine MAX+ Forced Air Duct is manufactured right here in the USA using premium fiberglass construction with a gel coat finish — the same material trusted in motorsports and offshore racing applications for its superior strength-to-weight ratio, rigidity, and long-term durability in harsh marine environments. Advanced 3D scanning technology ensures a precise, Lego-tight fit to the factory V8 cowling every time. It's surface-prepped with an adhesion primer so it's ready for your color of choice straight out of the box.

Performance Numbers

• 50%+ increase in ram air intake over the factory duct
• Significantly reduced intake air temperatures at WOT
• Retains 2–3 MPH in top-end speed — even more on boats running 100+ MPH
• Blocks exhaust fumes from re-entering the intake (station wagon effect)

Highlights

• Fiberglass construction with gel coat finish — USA manufactured
• Race-inspired F1 profile design that follows OE cowling lines
• Precision 3D-scanned fitment — drops in like a factory part
• Surface prepped with adhesion primer — ready to paint your color
• Includes 3M 4000 marine adhesive for a secure, permanent install
• Larger gains on 100+ MPH boats
• Air being forced into the engine is Non-consensual 😄

Fitment

• Mercury 250 V8
• Mercury 300 V8 Verado
• Mercury 300 V8 CMS
• Mercury 300R
• Mercury 450R
• Mercury 500R

Customer Reviews