3/8" Flow Control Valve - Pro Series

Introduced in 1994 the original Jet Works Flow Control Valve provides improved throttle response and much quicker starts by drying out your waterbox at low rpm and idle speeds. Tests have shown an average acceleration improvement of 10 feet over a non-equipped model in the first 50 feet. Without a flow control valve water fills up the water box and exhaust hoses, upon sudden acceleration all of this water must be forced out quickly before full exhaust flow can occur. This can cause a craft to feel slight hesitation and/or sluggishness, easily adjustable by turning the hex portion of the valve.The Flow Control Valve allows unrestricted water flow to the Stinger for better top speed yet it controls the amount of water at low speeds for better response. It also allows for an easier tuning of the Carburetors. It does not interfere with normal engine or exhaust pipe cooling and is compatible with all electronic water injection systems. Race Legal for All Classes. The Pro-Series is externally adjustable by turning the outer housing by hand. Pressure can be tested with pop off gauge. All PWC w/OEM or aftermarket exhaust systems (except Yamaha’s w/OEM exhaust).

Used by every Factory Team during the 2-Stroke Racing era including Kawasaki, Sea-Doo, Yamaha and Polaris. The Jet Works Flow Control even came factory equipped on some Factory Pipe Products Exhaust systems and OEM on Polaris Watercraft. Used by many, recommended by all, the Jetworks Flow Control Valve is the best and most noticeable performance upgrade for the price.

Can be installed on any aftermarket exhaust system by using the water fitting on the stinger and can be used in conjunction with a restrictor such as the Jetworks Water Restrictor Kit.

* IJSBA race legal. 2015 Revised version allows for lower pop off pressure. 

Ships via UPS or USPS Priority.  All "Open Box" items are excluded from our free shipping offer and are not returnable.

International Customers: Shipping charges reflect transportation costs only and do not include international brokerage fees, duties, GST/HST/PST, or other applicable taxes. Customers outside the United States may receive a separate invoice directly from the carrier for these additional charges.

If your order arrives damaged or appears defective, please submit a claim through our Customer Service Order Damage Form. Our team will review your submission and contact you within 24 hours (excluding weekends and holidays). All damage/defect claims must be reported within 48 hours of delivery.

An RMA# (Return Merchandise Authorization Number) is required for all returns.

Returns must be initiated through your Customer Account Portal within 10 days of delivery.

Returned items must be:

• Unused
• Uninstalled
• Unmodified
• Complete with all original packaging, hardware, manuals, and accessories

Returns not related to damage, defect, or an Atlantic Jet Sports shipping error are subject to a 20% restocking fee. Customers are responsible for return shipping costs.

Unauthorized returns will be refused at our shipping dock.

[View Full Return Policy & Return Instructions]

Non‑Returnable Items

The following items are final sale and not eligible for return, exchange, or store credit:

• Seat Covers
• Mat Kits, Mat Sheets
• Chin Pads
• Waterboxes
• Aqua Cart & Factory Zero Transportation/Beach Dollies, Totes, Display Carts, and all related Parts/Accessories
• Watercraft Stands
• Aqua Performance Watercraft Steps
• RRP Handlepoles
• Special Order Items
• Close‑Out Items

Electrical Components (non‑returnable):
Starter Motors, Regulators, Relays, CDI Units, Ignition Coils, Stator Coils, Stator Assemblies, Fuel Injectors.

All warranties are those of the manufacturer and not Atlantic Jet Sports. We will be happy to assist you in filing a warranty claim with the manufacturer, but please remember that the manufacturer determines whether a claim is approved or denied. Any modification to a product voids your warranty. All claims for consequential, physical, incidental, or special damage are hereby excluded.

Performance Product Use & Compliance Notice

Atlantic Jet Sports supplies high‑performance components engineered solely for closed‑course racing and sanctioned competition. These parts are not designed, tested, certified, or warranted for use on public waterways or on watercraft equipped with emissions‑controlled systems.

Installing or using these components may change the watercraft’s safety characteristics, emissions compliance, or legal classification. Using competition‑only products on public waterways may violate federal, state, or local regulations.

By purchasing, installing, or operating a watercraft equipped with these components, the user acknowledges and accepts full responsibility for all associated risks—including, but not limited to, personal injury, property damage, mechanical failure, or legal consequences. The user further agrees that Atlantic Jet Sports assumes no liability for damages arising from improper installation, misuse, or operation outside of competition environments.

For best performance and safety, Atlantic Jet Sports strongly recommends installation by a qualified technician experienced with high‑performance Personal Watercraft systems.

Product Installation Disclaimer

⚠️ Warning — Professional Installation Required

• Ensure the hull is fully ventilated and free of fuel vapors before using electric or battery‑powered tools. Failure to do so may result in fire, explosion, serious injury, or death.
• Disconnect the battery before performing any installation or maintenance to prevent accidental ignition, electrical shock, or unintended engine engagement.
• Allow the engine, exhaust, and surrounding components to cool completely before beginning work.
• No smoking, open flames, or spark‑producing devices should be present during installation.

This product is not intended for use on watercraft equipped with pollution‑control systems. Modifying or removing emissions‑related components may violate state or local laws and may render the watercraft illegal for use outside of competition.