sparkplugs for r129 119 engine

[pollockd17]

I'd like opinions on the use of platinum plugs in my 91 500sl as opposed
to conventional plugs...Thanks

[Lee Wireless]

Stick with the recommended plugs. Hundreds of posts on this site will say the same thing. Don't waste your money.

[Gusfazekas]

I have a '95 SL500 and I run the Bosch Iridium plugs and there is NO PROBLEM regardless of what has been written on the forum. I did this BEFORE I started following the forum for help and I have read all of the threads on this topic. Since I put them in, there has been absolutely no issues or misses with mine. Steve

[rocky raccoon]

I sort of agree with Lee with a caveat.

Platinum plugs should work just fine ... but ... they were intially developed for long life as compared to conventional copper plugs. For our cars (I have an '88 560SL) with aluminum heads I find it theraputic to remove, inspect, sandblast and reset plugs once per year anyway. I find many disagree with that practice but I have the horrors of finding a plug frozen into that aluminum head after being left in place for years.

I use copper core plugs since periodic removal offers the opportunity to change them if deemed necessary and they cost a lot less plus are the original factory recommendation anyway.

Bottom line is, I agree that platinums will work fine. Just don't get suckered into any kind of multiple electrode plug since that is just a sales gimmick. The laws of physics prevail and the spark will jump the point of least resistance at all times.