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🎄 Ace Race Parts will be closed from December 24th through December 26th for the Christmas holiday. Orders will be processed on December 23rd and December 27th in the order they are received. Expedited shipping orders are guaranteed to ship out if placed before the same-day shipping cutoff time (12 PM Pacific). Wishing you a Merry Christmas and Happy Holidays! 🎄
🎄 Ace Race Parts will be closed from December 24th through December 26th for the Christmas holiday. Orders will be processed on December 23rd and December 27th in the order they are received. Expedited shipping orders are guaranteed to ship out if placed before the same-day shipping cutoff time (12 PM Pacific). Wishing you a Merry Christmas and Happy Holidays! 🎄
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Radiator Caps & Filler Necks

Ace Race Parts offers a comprehensive selection of 6061 aluminum radiator filler necks in two common sizes—Small and Large—along with high-pressure radiator caps from Koyo and Mishimoto. Each radiator filler neck is precision CNC machined from billet 6061 aluminum and features a two-piece threaded design, ensuring a secure and reliable... Read More
Weld On Radiator Filler Neck - Small - Ace Race Parts

Weld On Radiator Filler Neck - Small (1.250" ID, 0.750" Outlet) - 6061 Aluminum

SKU 17001
$ 21.95 - $ 21.95
$ 21.95
$ 21.95 - $ 21.95
$ 21.95
25+ in stock

Ace Race Parts offers Weld On Radiator Filler Necks that are precision CNC machined from solid 6061 Aluminum billet and come with a 1/16" NPT x 1/4...

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Weld On Radiator Filler Neck - Large - Ace Race Parts

Weld On Radiator Filler Neck - Large (1.650" ID, 1.092" Outlet) - 6061 Aluminum

SKU 17002
$ 22.95 - $ 22.95
$ 22.95
$ 22.95 - $ 22.95
$ 22.95
25+ in stock

Ace Race Parts offers Weld On Radiator Filler Necks that are precision CNC machined from solid 6061 Aluminum billet and come with a 1/16" NPT x 1/4...

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Tank Filler Neck and Cap | Ace Race Parts

Tank Weld Bung with Thread On Cap - 1.000" ID - 6061 Aluminum

SKU 17003
$ 34.99 - $ 34.99
$ 34.99
$ 34.99 - $ 34.99
$ 34.99
25+ in stock

Ace Race Parts offers Tank Weld Bungs that are precision CNC machined from solid 6061 Aluminum billet and come with a thread-on cap featuring an O-...

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Tank Filler Neck and Cap | Ace Race Parts

Tank Weld Bung with Thread On Cap - 1.500" ID - 6061 Aluminum

SKU 17004
$ 34.99 - $ 34.99
$ 34.99
$ 34.99 - $ 34.99
$ 34.99
25+ in stock

Ace Race Parts offers Tank Weld Bungs that are precision CNC machined from solid 6061 Aluminum billet and come with a thread-on cap featuring an O-...

View full details
Tank Filler Neck and Cap | Ace Race Parts

Tank Weld Bung with Thread On Cap - 2.000" ID - 6061 Aluminum

SKU 17005
$ 38.99 - $ 38.99
$ 38.99
$ 38.99 - $ 38.99
$ 38.99
25+ in stock

Ace Race Parts offers Tank Weld Bungs that are precision CNC machined from solid 6061 Aluminum billet and come with a thread-on cap featuring an O-...

View full details
Tank Filler Neck and Cap | Ace Race Parts

Tank Weld Bung with Thread On Cap - 2.500" ID - 6061 Aluminum

SKU 17006
$ 45.99 - $ 45.99
$ 45.99
$ 45.99 - $ 45.99
$ 45.99
25+ in stock

Ace Race Parts offers Tank Weld Bungs that are precision CNC machined from solid 6061 Aluminum billet and come with a thread-on cap featuring an O-...

View full details
Tank Filler Neck and Cap | Ace Race Parts

Tank Weld Bung with Thread On Cap - 3.000" ID - 6061 Aluminum

SKU 17007
$ 59.99 - $ 59.99
$ 59.99
$ 59.99 - $ 59.99
$ 59.99
25+ in stock

Ace Race Parts offers Tank Weld Bungs that are precision CNC machined from solid 6061 Aluminum billet and come with a thread-on cap featuring an O-...

View full details
Mishimoto High Pressure Radiator Cap 1.3 Bar - Small (MMRC-13-SM) - Ace Race Parts

Mishimoto High Pressure Radiator Cap 1.3 Bar - Small (MMRC-13-SM)

SKU MMRC-13-SM
$ 0.00 - $ 0.00
$ 0.00
$ 24.95
$ 24.95 - $ 24.95
$ 24.95
Only 5 left!

Getting the most out of your performance parts comes down to the details. When faced with hard driving conditions, a vehicle's cooling system becom...

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Mishimoto High Pressure Carbon Fiber Radiator Cap 1.3 Bar - Small (MMRC-13-SMCF)

SKU MMRC-13-SMCF
$ 0.00 - $ 0.00
$ 0.00
$ 37.95
$ 37.95 - $ 37.95
$ 37.95
Only 4 left!

Mishimoto has developed a carbon fiber radiator cap to enhance the style of your engine bay while maintaining the pressure in your cooling system. ...

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Mishimoto High Pressure Radiator Cap 2.0 Bar - Small (MMRC-20-SM) - Ace Race Parts

Mishimoto High Pressure Radiator Cap 2.0 Bar - Small (MMRC-20-SM)

SKU MMRC-20-SM
$ 24.95 - $ 24.95
$ 24.95
$ 24.95 - $ 24.95
$ 24.95
Only 2 left!

Getting the most out of your performance parts comes down to the details. When faced with hard driving conditions, a vehicle's cooling system becom...

View full details
Mishimoto High Pressure Radiator Cap 1.3 Bar - Large (MMRC-13L) - Ace Race Parts

Mishimoto High Pressure Radiator Cap 1.3 Bar - Large (MMRC-13L)

SKU MMRC-13L
$ 24.95 - $ 24.95
$ 24.95
$ 24.95 - $ 24.95
$ 24.95
Only 2 left!

Getting the most out of your performance parts comes down to the details. When faced with hard driving conditions, a vehicle's cooling system becom...

View full details