This is a difficult question to answer, and is in fact one of our most frequently asked questions, but in general you can use any spark plugs with Magnecor Race Wires.
On a full race engine, spark plugs specifically designed for racing should be chosen. A decision as to which type and brand should be made only after investigating which spark plug is used by other competitors racing engines and vehicles similar to yours. You might find it easier to get this information from spark plug suppliers, although experimentation will always be necessary.
On production vehicles used exclusively on the street in standard tune, often the vehicle manufacturer’s original spark plugs are a good choice, except where a double platinum version is available — which is a better choice. Always use resistor spark plugs if the vehicle manufacturer specifies them, as the resistance is there to not only to help reduce RFI, but also to extend the life of spark plugs by reducing tip erosion. Unless you know someone with an identical vehicle who can vouch for spark plugs that are heavily promoted and promise extra horsepower and fuel mileage, it’s best to avoid them, as these spark plugs rarely fulfill the claims made — and always, you will be paying more in the price for the promotion that makes you think you need them than the cost to manufacture the actual spark plugs!
After fitting a high-output ignition most people are tempted to widen spark plug gaps, and although the latest aftermarket ignition systems can easily cope with the extra voltage necessary to jump the larger gap, often the smaller diameter spark plugs used in most recent street engines will cause an engine misfire (usually at high RPM) after a few miles because the spark tends to track down the coating formed from combustion on the center electrode insulator in preference to crossing the widened spark plug gap. Also, wider-gap spark plugs will wear out prematurely. Owners of some modified street cars have found differences in acceleration response by altering spark plug gaps, but generally, if Magnecor Race Wires are used, the best response will be attained with a standard gap. Again, experimentation is always necessary.
VERY IMPORTANT — PLEASE NOTE:
Because of the huge variety of different brand spark plugs currently available, care needs to taken to ensure the spark plugs you use to replace worn out plugs are identical in proportion. This is particularly important if your engine uses multi-part extension type spark plug connectors with top seals that need to fit flush with the valve cover. You need to ensure that the height of each spark plug from the gasket seal to the top of the spark plug is identical to the original factory spark plugs, if you think the height of the plugs you are about to fit are different to that of the originals, please contact us before ordering. We have seen spark plugs, sold as aftermarket replacement and/or performance plugs, that can be up to 5mm taller (top seals will be pushed up) and 5mm or more shorter (spark plug wires may not properly engage spark plugs).