sabru missfire cylinder 1 3 changed pluges and power pack what could it be

Uhhh, plug wires ? are they damaged ? arcing? can they pass an ohm check of 5000 ohms per foot ? then bending during the test, inspecting for insulation damage, white dots ? They are actually a cable, the current that flows can burn any spot along their construction that contains resistance. They last and last, but does anyone really know how to diagnose a good one ? or a failed one? Replacing them with highest quality can get you metals in use that increase conductivity and reduce likelyhood of corrosion, using dielectric when assembling can promote fully seated plug boots, moisture free connections, and low impedance.

The subaru part fits best and has what you need. facsimilies can be trouble in fitting and difficult to properly connect. extra time and finesse is required to get them right but they can still function.

I have used NGK plugs on those, you can get lasting mileage from the plug based on what it is made of. cheaper ones need replacing more often, and as the gap widens with wear, they tend to misfire. Even the parts you just put on can be at fault, you must retest each one. Aftermarket ignition parts = ?