Spark plug choice...
- Thread starter demq
- Start date
Until I tried the Bosch Platinum+4 I also would always say the factory spec ones. I found the plus fours to be excellent performing and I have had them in for just over 30K miles in my '89 325i w/ Conforti chip and they perform like new yet. As a plus, you do not have to gap them. DO NOT use the earlier platinums or the plus 2 plugs. They do not perform in 325i BMWs nearly as well as a stock plug. The plus 4s are similar to (not the same as) the factory M3 plugs (4 electrode). They were recommended to me by some fellow motorheads as well as a dealer master technician that tried them in their 325s and liked them so I gave them a try. I will replace them with Bosch plus 4s when needed.
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Something Different
Hate to post this & be different but...NGK Gold Pallidium with the thin wire electrode seem to be a good choice. It's not a projected tip as the Bosch is. I was skepticle, expected them to go flat quickly but after close to one years time, they still run like they did when installed. Cost about $3.50ea. I just asked for whatever NGK Pallidium plug was called for in my car, not sure why NGK doesn't suggest the projected tip.
Hate to post this & be different but...NGK Gold Pallidium with the thin wire electrode seem to be a good choice. It's not a projected tip as the Bosch is. I was skepticle, expected them to go flat quickly but after close to one years time, they still run like they did when installed. Cost about $3.50ea. I just asked for whatever NGK Pallidium plug was called for in my car, not sure why NGK doesn't suggest the projected tip.
A lot depends on whether it is an "e" or an "i" engine as well. Some brands work better than others in different engines. The factory itself used both Bosch and Beru as original equipment. It would be interesting to see how the NGK plugs are after 30K miles. The Bosch Platinum+4 plugs are still like new at 30K miles in my 325i. They are priced at $4.99 -$5.99 each though. I have heard some good things about Silverstones but I cannot confirm through any personal knowledge how good they are. Early platinums were not worth a dam in 84-85 318i M10 motors ( the silver tips were best) or in "i" motors but worked in "e" engines.