What spark plugs for a modded e30?

[MrK]

Hey everyone,

I'm new around here, (see my intro thread under General discussion), I just wanted to ask for a clarification...

Me and my mechanic have reached an impass. He put in Bosch + Platinum sparks for my modded e30 325i (again see the intro thread for more details), and from what I've read here, normal Bosch +4s are preferable to Platinums. His arguement is that the platinum is a 'hot' plug, which is better for a high-compression engine than the normal Bosch +4.

Anyone know what's the final word on this? If you need more info on my engine let me know...

Thanks in advance,

Mr. K

[lordofthewaters]

I wouldn't use platinums......
There is a signature pic someone here has somewhere, of a kitten with a rifle screaming no platinum plugs, a BMW is not a Ford!

What mods have you done? Have they affected the compression? etc and so on.......

[DaN]

You dont really want a "hot" plug on a high compression high performance engine. Though the m20 is not high compression or high performance. Platniums are only good as a long lasting, self cleaning plug.
No one recommends they should be used in an m20.

Get regular bosch supers and be done with it.

[RobertK]

You want to stick to a copper plug like the Bosch Supers or NGK V-Powers and even the Denso equivelant is a pretty good plug.

M20's don't like platinums especially Bosch +4 Platinums. So you're mechanic is only semi right about not using platinums.

[MrK]

Thanks for all the replies so far ppl. Really appreciate it.

And to answer lordofthewaters, I've put high-compression forged pistons in there, raising the compression quite a bit yes. Does that make a difference?

MrK