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Koyo 1.3 Bar High Pressure Radiator Cap Hyper Red (Part Number: )
Koyo 1.3 Bar High Pressure Radiator Cap Hyper Red (Part Number: )
Koyo 1.3 Bar High Pressure Radiator Cap Hyper Red (Part Number: )
Koyo 1.3 Bar High Pressure Radiator Cap Hyper Red (Part Number: )
Koyo 1.3 Bar High Pressure Radiator Cap Hyper Red
Read 11 Reviews | 6 Q&As
Part # SK-C13
msrp: $30.00

In stock! Ships same day
Universal part

Features & Product Details

If you just purchased the Koyo Radiator, you can maximize the performance with the Koyo 1.3 Bar High-Pressure Radiator Cap! These are finished in Hyper Red, and reviewers of this radiator cap have been pleased with the looks, and performance of this radiator 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. These are highly recommended for use with every KoyoRad All Aluminum Radiator (when applicable). 

The KoyoRad Hyper cap is crafted in Japan from high-quality materials to ensure longevity and performance from your KoyoRad Racing Radiator. 


Brand: Koyo
Opening Point: 1.3 Bar
Mfgr. Warranty: Initial Start UP
Condition: New Product
Return Policy:

RallySport Guarantee - 30 Days

Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.
RallySport Guarantee



11 Reviews
5 out of 5 Stars
5 Stars
4 Stars
3 Stars
2 Stars
1 Stars
Customer Photos and Videos
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Great price great value 1 year ago
5out of 5stars

Bought this and a koyorad oem replacement radiator. You can't go wrong with rallysportdirect and KOYORAD makes a great product.
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Great looking and well made cap 1 year ago
5out of 5stars

Needed a high pressure cap and my Cobb one was trash so was recommended this one by a RSD team member, and I love it. Looks great, simple and most of all does it's purpose. When I ordered my brother in law a Koyo Rad for his 88 RX-7, I made sure to pick up another one of these. Thanks as always RSD for the fast shipping and great price!
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I like it 2 years ago
5out of 5stars

I like it. I mean what more do you want to know? its a freaking radiator cap. It screws on nice and tight. Seems to seal/handle the pressure very well. Worth it ("thumbs up" emoji)
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Great Cap 3 years ago
5out of 5stars

I purchased this cap to push my order into the free shipping area, if I am being honest lol. The shipping was quick and the packaging was solid. It installed without a hitch and I haven't had any issues with it. Seems to be a quality product.
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Great Product 3 years ago
5out of 5stars

What can I say its a rad cap. It looks good and pushed my order into the free shipping area lol. Listen it was well packaged and shipped quickly as always. Fits like a glove and no issues as of yet.
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  • Q: How many Koyo radiator caps do I need for Subaru sti  RL11 months ago

    So so I need to buy two of these caps to put one on my Koyo radiator and the other on the top reservoir tank?
  • Q: fitment and sizing  gray.s2k1 year ago

    will this cap fit my 2-row core mishimoto radiator in my honda s2000? i cant seem to find a good high pressure cap that will for sure fit. i believe it might be type F

This Part Fits

Universal Product
This item is non application specific.
Please verify compatibility before purchase. May require some modification for proper installation.