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MSD Ignition 8620 Crank Trigger Kit BBC 8"Balancer Crank Trigger.

MSD Ignition 8620 Crank Trigger Kit BBC 8"Balancer Crank Trigger.

SKU: 8620
Regular price $469.95 USD
Regular price Sale price $469.95 USD
Sale Sold out


For a long time, racers have known that one of the best things to do to an engine to improve its performance is to stabilize the ignition timing. The MSD Flying Magnet Crank Trigger system does exactly that by using four magnets embedded in an aluminum wheel. Although similar in appearance to other crank triggers, the MSD Flying Magnet design works on a different principle. Most crank triggers have a wheel, with steel studs sticking out, bolted to the harmonic balancer. As the crankshaft turns, the studs pass by a stationary magnetic pick-up, triggering the ignition. This pick-up can be triggered by other bolts, debris or even vibrations which will cause a loss of power or engine damage. The MSD Flying Magnet Crank Trigger uses four magnets secured in the aluminum trigger wheel that pass by a stationary non-magnetic pick-up to trigger the ignition. This "flying magnet" design produces accurate trigger signals and the non-magnetic pick-up cannot be false triggered. Each Flying Magnet Crank Trigger includes a two-piece mounting bracket for the non-magnetic pick-up that in most cases will work on either the passenger side or driver's side of the engine (the SB Chrysler and SB Ford brackets mount on only one side). The CNC-machined aluminum bracket securely holds the pick-up in place and is slotted to provide a wide range of timing adjustment. Spacers are included so you can mount the bracket on engines with standard motor mounts or engines with a .25" motor plate. These systems will trigger MSD 6, 7 and 8 Series Ignitions and all MSD Timing Accessories.


    Year Make Model Submodel Engine Size
    1979 - 1986 GMC K3500 4.25/8 V
    1976 GMC Jimmy 4.25/8 V
    1987 - 1988 Chevrolet V30 4.25/8 V
    1975 - 1986 Chevrolet C20 4.25/8 V
    1975 - 1986 Chevrolet C20 Suburban 4.25/8 V
    1975 - 1978 GMC C25 Suburban 4.25/8 V
    1979 - 1986 GMC C2500 4.25/8 V
    1975 - 1978 GMC C35 4.25/8 V
    1975 - 1986 Chevrolet C30 4.25/8 V
    1979 - 1980 GMC C1500 4.25/8 V
    1975 - 1980 Chevrolet C10 4.25/8 V
    1977 - 1986 Chevrolet K30 4.25/8 V
    1979 - 1986 GMC C2500 Suburban 4.25/8 V
    1976 - 1977 GMC K25 Suburban 4.25/8 V
    1976 - 1980 Chevrolet K10 4.25/8 V
    1976 - 1978 GMC K25 4.25/8 V
    1987 - 1989 GMC R3500 4.25/8 V
    1975 - 1976 GMC G25 4.25/8 V
    1979 - 1980 GMC C1500 Suburban 4.25/8 V
    1975 - 1976 Chevrolet G30 4.25/8 V
    1976 - 1978 Chevrolet K5 Blazer 4.25/8 V
    1975 GMC Sprint 4.13/8 V
    1980 GMC K1500 4.25/8 V
    1985 Chevrolet K20 Suburban 4.25/8 V
    1987 - 1989 GMC V3500 4.25/8 V
    1975 GMC Sprint 4.25/8 V
    1975 - 1978 GMC C15 4.25/8 V
    1975 - 1978 GMC C25 4.25/8 V
    1975 - 1980 Chevrolet C10 Suburban 4.25/8 V
    1979 - 1986 GMC C3500 4.25/8 V
    1987 - 1988 Chevrolet R30 4.25/8 V
    1989 Chevrolet V3500 4.25/8 V
    1975 - 1978 GMC C15 Suburban 4.25/8 V
    1989 Chevrolet R3500 4.25/8 V
    1976 Chevrolet G20 4.25/8 V
    1976 - 1978 Chevrolet K20 4.25/8 V
    1975 - 1976 Chevrolet Caprice 4.25/8 V
    1975 Chevrolet Monte Carlo 4.25/8 V
    1975 - 1976 Chevrolet Impala 4.25/8 V
    1975 Chevrolet Malibu 4.25/8 V
    1976 GMC K15 4.25/8 V
    1976 GMC G35 4.25/8 V
    1975 Chevrolet Bel Air 4.25/8 V

    Brand MSD
    Color Red
    Diameter 8"
    Emission Code 4
    Make Chevy
    Product Type Crank Trigger Kit
    Sensor Dimensions 3/4" x 2.25"
    Sensor Type Non Magnetic
    Trigger Type 4X
    Warning California Proposition 65
    Warranty Limited 1 Year Warranty
    Wheel Width 3/8"
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    Return Policy

    We accept returns on products within 30 days of delivery. Return shipping is the responsibility of the buyer unless we, the seller, are at fault.

    Fault reasons include but are not limited to:
    • Buyer was shipped the wrong product
    • Buyer was shipped a damaged product
    • The product page had incorrect fitment and the part does not fit the Buyer's vehicle
    The Buyer will not be refunded outbound shipping unless the Seller (Modern Day Muffler & Brake) is at fault.
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    Returns must be sent to this address:
    Modern Day Muffler & Brake
    774 Broad Street
    Wadsworth, OH 44281
    Products returned directly to a manufacturer or the incorrect address may be issued a deduction or denied a refund entirely.
    If a product was delivered outside the 30 day return window or is no longer in original condition please contact us as we may be able to issue a refund in store credit and/or with a deduction. If this is the case please Contact Us as these situations are handled on a case by case basis.
    If there are any questions, concerns, or doubts about return eligibility please Contact Us and we would be more than happy to assist you.
    This page and policy were last updated: July 14th 2023


    This is the line that runs from the front of the vehicle to the rear. On most vehicles it connects to a junction then you will have rear axle lines. On a few cars the intermediate lines will connect to the rear wheels. It is recommended to change the axle lines if you are replacing the intermediate lines.

    Our kits include all of the solid metal lines for that section of the vehicle.

    We are happy to help! Please help us to help you by going to our return form and filling out the form as best as you can in order to request a return.

    • Modern Day stands by our parts and is happy to accept returns within 30 days of purchase. Parts must be in new condition.
    • If a part arrives damaged, or is defective, Please report it to us immediately. So we can handle it for your promptly.

    Yes but you will need to order in advance. All of our items are not stocked at our location. So please place your order online and we will notify you when it is ready for pick up.

    Unfortunately we cannot offer single lines outside of kits

    Yes, all are covered by the manufacturer's standard warranty. Most warranties cover the cost of parts. Any installation or other fees are non-refundable.

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    Orders typically Arrive within 3 to 10 days depending if it is a stocked item or something we have manufactured at time of sale.

    Yes please send us a message through our custom orders page.

    Yes, but items sent out of the continental U.S. may incur additional charges based on their destination

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    Check it again tomorrow. It takes up to 1 day for the carrier to give status and a delivery date. UPS and FedEx provide delivery dates, USPS usually does not but they take no longer than 5 business days.

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    Yes! Thank you for your military service!

    Warranty Information

    Customer service is our top priority and because we value your time and energy we ask you to visit our Contact Us page and reach out so that we may assist you in finding the correct warranty for your product. Please include your name, the name on the order, the order number, and the SKU of the product to ensure the quickest and most accurate response to your inquiry.

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