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SKU: 20-1127
Radium Engineering FCST Adapter – 6-Bolt to 3-Bolt Filler Neck
Update your older Radium Fuel Cell Surge Tank (FCST) with modern fill necks using the Radium Engineering 6-Bolt to 3-Bolt Filler Neck Adapter. This precision-machined adapter allows you to install newer 3-bolt fill necks onto older FCST models that originally used a 6-bolt filler neck pattern.
This is an essential upgrade for builders who want to use the latest Radium fill neck designs on existing surge tanks without having to replace the entire unit. The adapter is made from high-quality materials and provides a secure, leak-free connection between the tank and the fill neck.
Key Features
- 6-Bolt to 3-Bolt Conversion – Allows modern 3-bolt fill necks on older 6-bolt FCST models
- Direct Bolt-On Solution – No modifications to the fuel cell required
- Precision Machined – Ensures proper fitment and sealing
- Leak-Free Connection – Designed for reliable, fuel-tight performance
- High-Quality Construction – Built to Radium Engineering’s exacting standards
- Easy Upgrade Path – Cost-effective way to modernize older surge tanks
Specifications
| Detail | Value |
|---|---|
| Brand | Radium Engineering |
| Type | FCST Filler Neck Adapter (6-Bolt to 3-Bolt) |
| Compatibility | Radium Fuel Cell Surge Tanks (FCST) |
| Function | Adapts older 6-bolt tanks to modern 3-bolt fill necks |
| Material | High-Quality Machined Aluminum |
| Country of Origin | United States |
| Warranty | Radium Engineering Limited Warranty |
Whats Included
- Radium Engineering 6-Bolt to 3-Bolt Filler Neck Adapter
- Installation Hardware (if applicable)
- Installation Instructions
Product Notes
- Designed exclusively for Radium Fuel Cell Surge Tanks (FCST)
- Professional installation is recommended
- Verify your current fill neck bolt pattern before ordering
This Part Fits
| Application | Notes |
|---|---|
| Radium FCST (Older 6-Bolt Models) | Allows use of modern 3-bolt fill necks |
| Performance Fuel Systems | Ideal for race, drift, rally, and off-road builds |
Why Choose Radium Engineering?
- Industry leader in high-performance fuel system components
- Precision-engineered parts trusted by professional racers and tuners
- Focus on quality, fitment, and real-world performance
- Made in the USA with a commitment to excellence
Frequently Asked Questions
- Q: What does this adapter do?
- A: It allows you to install a modern 3-bolt fill neck onto older Radium FCST models that originally used a 6-bolt filler pattern.
- Q: Do I need to modify my fuel cell?
- A: No. This is a direct bolt-on adapter that requires no modifications to the tank.
- Q: Will this work with any fill neck?
- A: It is designed to work with Radium’s modern 3-bolt fill necks on older 6-bolt FCST models.
- Q: Is professional installation required?
- A: While many experienced builders can install it, professional installation is recommended to ensure a proper, leak-free seal.
Shipping & Handling
- Method: UPS Ground or FedEx Ground
- Availability: In stock – ships same or next business day
- Packaging: Secure Radium Engineering retail packaging
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