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Distributor O-Ring Kit for Billet Chevy Distributors
InfoVehicle Info Needed
MSD IGNITIONPART NUMBER: 121-8494

Distributor O-Ring Kit for Billet Chevy Distributors

$2244
1 left in stock
ShippingShips on Nov 02, 2026
Lowest PriceLowest Price Guarantee

Replacement Parts
Replacement Distributor Housing O-Ring Kit
  • Fits All Chevrolet Billet Distributors
  • Seals the Distributor Housing to the Block
  • Helps Control Oil Pressure in Modified Blocks

    On a modified block, oil can find its way up past the distributor housing and cost you pressure where you need it. This O-ring kit seals the housing to the block on Chevrolet billet distributors, and it is also the service part to reach for any time the original O-rings have taken a set or been nicked during removal.

    MSD 8494 Distributor O-Ring Kit Features:

    • Fits all Chevrolet billet distributors.
    • Seals the distributor housing to the block.
    • Helps control oil pressure on modified blocks.
    • Direct replacement service part.
    • MSD has the Best Distributor for Your Vehicle

      MSD Billet and Pro-Billet Distributors with CNC-machined billet aluminum housings have maintenance-free magnetic pickups guided by a sealed ball bearing located at the top of the housing.

      Show More

      For drivers who demand performance, precision, and reliability, the MSD Billet & Pro-Billet Distributors are the gold standard in ignition control. Whether you’re building a high-performance street machine or a dedicated race car, MSD delivers the spark accuracy and rugged construction you need to push your engine to the limit.

      Each MSD Pro Billet Distributor is CNC-machined from high-quality billet aluminum for maximum strength and minimal flex, even at high RPMs. The polished housing isn’t just for looks—it’s built to last, resist corrosion, and endure extreme engine conditions. Inside, a maintenance-free magnetic pickup provides accurate trigger signals, while a hardened steel shaft with a sealed ball bearing ensures long-lasting performance.

      The Pro Billet Distributor MSD lineup is compatible with MSD ignition controls and features an easy-to-adjust mechanical advance, making tuning a breeze. Whether you're dialing in timing for the street or strip, you’ll get consistent spark delivery and smoother acceleration across the power band.

      If you're upgrading a small block Chevy, the MSD Pro Billet Distributor SBC is a perfect match, offering drop-in compatibility and serious performance gains. These distributors are designed to meet the needs of racers and enthusiasts who won’t settle for stock performance.

      Step up your ignition system with the proven power and reliability of MSD Billet and Pro-Billet Distributors—engineered to ignite your build's full potential.

      Whether you’re working on a high performance race car or a daily driver street machine, precise and durable ignition components are always going to be a real must. An MSD billet or Pro-Billet distributor is a distinct upgrade from your OEM distributor setup, with accurate spark delivery and durable, rugged construction that will let you really push the envelope of your engine’s performance. 

      Performance Benefits & Key Features

      Every MSD Billet distributor is machined from top grade billet aluminum and a hardened steel shaft, with maintenance-free magnetic pickups for accurate and consistent ignition signal, and a precision ball bearing set with long sintered bushing guide at the top of the housing. The polished housing looks great, but it’s more than just a dress-up feature; it’s designed to resist corrosion and to hold up under some of the most extreme engine conditions. 

      The Pro-Billet and MSD Billet lineup at JEGS is designed for compatibility with other MSD ignition components, with a mechanical advance that’s easy to adjust to dial in the timing you need on the strip or street. It’s easy to adjust it to your setting and you’ll get reliable spark delivery and stronger, smoother acceleration across the power band. For older applications, select MSD Billet distributors are equipped with vacuum advance. 

      Fitment, Compatibility & Applications 

      For small block Chevrolet applications, MSD’s Billet and Pro-Billet distributors are designed for drop-in installation. Distributor setups are available for small block and big block Chevrolet V8s, AMC V8s, Buick (including Nailhead V8s), Cadillac, small block and big block Ford engines, Ford flathead V8s, and big block and small block Chrysler (including first-gen Hemi V8s). Along with distributors, this is your one-stop-shopping destination for full ignition upgrade packages from MSD, including the distributor, cap, coil, coil wire, plug wires, as well as a digital 6AL ignition control box for later model Chevrolet small block applications. 

      Plug wires are standard 8.5mm size and can be cut to fit your desired length, and of course MSD’s iconic red hardware and plug wires look great under the hood of any car. Regardless of what kind of vehicle you’re driving and what kind of V8 it’s equipped with, an MSD Billet distributor or a full ignition upgrade of MSD components is a great way to squeeze a little more performance, response and dependability out of your setup.

    Part TypeDistributor O-Ring
    Product LineMSD Billet & Pro-Billet Distributors
    BrandMSD IGNITION
    Package Height1.5
    Package Width6.0
    Package Length7.8
    Weight0.1 PG
    Part CategoryPerformance Parts
    ColorBlack
    QuantitySold as a kit
    Distributor TypeAccessories
    Part FitmentSemi Universal
    Vendor Part Number8494
    Package Qty1
    Package TypeEA

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    Some parts are not legal for use in California or other states with similar laws / regulations
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