OEM coil packs are very limited, the spark tends to weaken around the 3500 rpm range, Upgrade today to Performance coils and keep spark strong to 6000 RPMS and gain approximately 5 RWHP, and at the same time upping your mileage about a half mile per gallon, combine these with our performance wires and performance spark plugs and regain and enhance the performance of your Viper Truck.