Dis-4 Plus High Output High Output Distributorless . 2, 3 Or 4-Coil Pack MSD IgnitionFor full bred drag race engines running high boost pressures from turbos, blowers or nitrous we offer a Higher Output version of the DIS Ignition Control. The DIS 4 Plus HO Ignition produces an incredible 170 millijoules of spark energy with 470 primary volts. This increased output will light up fuel mixtures even under extreme cylinder pressures. Two adjustable Rev Limits 10 18 Volts, Negative Ground Adjustable retard stage Ignition Interrupt Circuit