WnSEu LS coolant crossover kit AN4 stainless steel with steam vent and aluminum fittings

WnSEu MSCRP AN4 Fuel Brake Line LS Stainless Coolant Crossover Steam Vent Kit is a stainless-steel and aluminum alloy plumbing kit engineered to replace factory lines on LS-series engines and add a routed coolant crossover with steam venting and AN4 fittings.

This kit is designed for owners and shops working on GM LS-family engines (LS1, LS2, LS3, LS6, LS7, LS9, LSX and compatible variants) who need durable, corrosion-resistant replacement lines and a more serviceable coolant crossover with steam vent capability. Built from quality stainless steel and aluminum alloy components, the kit simplifies plumbing in custom installations and track applications. Some vehicle-specific fitments may require confirmation with installation personnel before purchase.

Will this kit fit my LS engine and application?

Compatibility covers most common LS family engines, but not every vehicle variant is shown. Confirm fitment with your installer or measure against your existing hoses and hardlines to be certain. Some adapters or bracket adjustments may be required for retrofits or highly modified engine bays.

• Covers LS1, LS2, LS3, LS6, LS7, LS9, LSX family engines
• May require adapters or trimming for non-standard configurations
• Professional installer confirmation recommended before ordering

How does the kit improve coolant routing and steam management?

The included coolant crossover and steam vent let trapped air escape and provide a cleaner, more direct path between cylinder heads and the radiator. Improved routing reduces hotspots and makes bleeding the system easier after maintenance or engine swaps. It’s not a cooling performance claim but a practical plumbing improvement for serviceability and reliability.

• Hardline coolant crossover for cleaner head-to-head routing
• Steam vent port simplifies bleeding and reduces air pockets
• AN4 connections for secure, leak-resistant fittings

What materials and construction should I expect?

The kit uses stainless steel for corrosion resistance and aluminum alloy components where light weight and machinability are needed. These materials hold up better than many factory soft lines under heat and vibration, and they present a finished look in custom engine bays. Proper installation and torqueing of AN fittings are important to ensure a leak-free system.

• Stainless-steel lines resist corrosion and swelling
• Aluminum alloy fittings and brackets for lightweight strength
• AN4 fittings for reliable, serviceable connections

What should I know about installation and maintenance?

Professional installation is recommended because correct routing, fitment and sealing of AN fittings require workshop tools and experience. Inspect threads, use appropriate thread sealant if specified, and pressure-test the cooling system after installation. Periodic checks for tightness and corrosion will keep the kit functioning properly.

• Professional installation recommended for best results
• Pressure-test cooling system after install to verify sealing
• Inspect fittings and lines periodically for wear or leaks

Who is this for: The WnSEu MSCRP AN4 Fuel Brake Line LS Stainless Coolant Crossover Steam Vent Kit is aimed at engine builders, performance shops and DIY mechanics installing or upgrading GM LS-family engines who want durable, serviceable hardlines and improved coolant routing. It’s suitable for restorations, swaps and track-prep projects where corrosion resistance, AN-style plumbing and an accessible steam vent are priorities. If you’re uncertain about fitment, consult your mechanic before purchasing to confirm any model-specific adaptations.