The Precision Raceworks Engine Coolant Reservoir Cap is a functional and stylish upgrade for any engine bay. It replaces the factory cap rather than covering it, using durable billet aluminum construction for long-lasting protection and dependability.
Available in Black, Blue, and Silver finishes, each cap incorporates the OEM pressure relief valve internals to maintain proper system function. Installation requires swapping the pressure relief valve from your original cap, ensuring a reliable fit and safe operation.
Key Features
| Product Type | Fluid Caps |
| Material | Billet aluminum |
| Donor Cap Part Number | BMW Part number 17117639021 |
| Brand | Precision Raceworks |
| Compatibility | BMW F Series, G Series, Toyota Supra |
| Installation | Requires swapping pressure relief valve from original cap |
| Color Options | Black, Blue, Silver |


Highlights
- Replaces the factory cap instead of covering it
- Durable billet aluminum construction
- Incorporates OEM pressure relief valve internals
- Available in Black, Blue, and Silver finishes
- Requires swapping the pressure relief valve from your original cap
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Materials & care
Constructed from billet aluminum for long-lasting durability. To maintain appearance, clean with a soft cloth and mild soap, then dry thoroughly.
Compatibility
Fitment NoteIf the primary expansion tank cap matches the following:

A different coolant expansion tank cap is required for use as the donor cap.
BMW Part number 17117639021

How to use
Product Note:
These require assembly and swapping the pressure relief valves from the original caps to the new billet caps.
Frequently asked questions
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