This is a good quality plug for a stock 948 or 1500. Unfortunately, the non resistor plug everyone used in the past isn't realidy available anymore. If you're running a 1275 or higher compression you may want this plug which is good for up to about 10:1 compression. You may be able to go higher, we haven't yet. If you're running very high compression, you may want to go to a colder plug. We also carry stock plugs in Champion or Bosch. Plugs are sold each.