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5X Racing Race Spec Brass Exhaust Header Nut Kit for Miata

Miata Downpipe Nuts

23993553 - 5XR-RSBHN
Kit includes 3 header/downpipe nuts to replace all of the problematic OEM original nuts

  • 19mm flange with 10 X 1.5 mm threads
  • OEM thread size with deeper flange for more thread engagement and socket area

    If you've ever worked on a Miata, you know the header to downpipe nuts are a very common source of frustration and strip/seize very easily. These brass replacements will ensure peace of mind and ease of maintenance when you're at the track and need to change a transmission or remove the exhaust for any reason

  • Limited Supply: only 1 remaining
    Shipping: USPS Priority or UPS Ground
    Pricing: $50.00


    If you've ever raced your Miata, you know the downpipe needs to be removed a lot and the nuts will seize to the threads easier than they should. At the track, many racers who needed to change out a transmission have surely experienced this, and it's just worth the cost to have reliable fasteners in order to ensure you're getting the most out of your expensive race weekend. These highly developed brass nuts were created to solve that problem.

    These are 14mm Hex 360 Brass nuts, 19mm long, and have a 19mm flange with 10 X 1.5 mm threads. The extra length makes them much easier to service and covers all of the previously exposed threads. Mazda likely chose the non standard thread to reduce seizing but that created a problem with people forcing a 10 X 1.25mm nut on the stud and damaging the thread creating even more issues. These nuts are easily identified solving another potential problem of them being used elsewhere damaging threads. Lastly, they work really well on the Turbo applications and can be counterbored to increase the grip length if needed (although has not been needed yet).


    • 23993553 - 5XR-RSBHN
    • 23993553
    • 5XR-RSBHN
    • 5X Racing
    • Available
    • New

    Shipping Information

    • Item Requires Shipping
    • 1.0 lbs.
    • W6.0000” x H1.0000” x L10.0000”
    • USPS Priority or UPS Ground

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