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Free Shipping Over $299.99

Free Shipping Over $299.99

Orders of $299.99 or more ship free within the continental U.S.
Shipping to Alaska and Hawaii is additional and not included.
We do not ship international at this time.

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This part does not have vehicle specific fitment. Please contact us if you need fitment assistance.

Koyo Radiator Cap
Part Number: SK-C13

★★★★★ ★★★★★ 3 Reviews
Koyo Radiator Cap-A1
Koyo Radiator Cap-A2
Koyo Radiator Cap-A3
Koyo Radiator Cap-A4
Images may be for reference only

Koyo Radiator Cap
Part Number: SK-C13

★★★★★ ★★★★★ 3 Reviews
Was: $49.20
Save: $10.61 (22%)

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10+ In Stock

Product Details

Part Number: SK-C13
Brand: Koyo Radiator
UPC: 847839000753

Designed to fit the Koyo radiator only, Part # SK-C13 Deep plunger fits all Koyorad radiators w/ filler necks

Extract every ounce of cooling efficiency from Koyorad All Aluminum Performance Radiators with a genuine Koyorad Hyper Cap! This Koyorad Hyper Cap withstands an increased valve pressure rating of 1.3kgf/cm2 (1.3 bar) (18.9 psi) (130 kPa) which increases the boiling point of water and relieves high performance engines of excessive heat. A genuine Koyorad Hyper Cap is recommended for use with every Koyorad All Aluminum Performance Radiator (when applicable). This Koyorad Hyper Cap is manufactured in Japan from high quality components to ensure longevity and performance from your Koyorad Racing radiator.

Why is increased Pressure Better?

Its simple. When water is pressurized, its natural boiling point is increased. Most modern vehicles are equipped with a 0.9 Bar pressure cap. Koyorads Hyper Cap is rated at 1.3 Bar which increases the boiling temperature of your coolant to 267.80 degrees Fahrenheit. That is nearly a 56 degree increase over water's normal boiling point. By increasing the boiling point of water, an engine's cooling system will have the added heat capacity, maximizing performance under ever-changing racing conditions.

WARNING: This product may contain chemicals known to the State of California to cause cancer or birth defects.

Vehicle Fitment

This part does not have vehicle specific fitment

3 Reviews ★★★★★ ★★★★★

★★★★★ ★★★★★
5/5.00 Stars out of 3 Reviews
Write a Review
Made in japan!
Ep3guy | September 11th, 2022
Super cool packaging, lots of Japanese writing
Blake Beard | September 4th, 2014
What else can be said? It fits the koyo radiator like a glove and looks great!
Koyo Cap for Koyo Radiator Cap
Kevin Choi | July 29th, 2010
it fits only koyo radiator. it worked great~! it's just cap.