Spark plugs?

[Interceptor]

Hi all,

I can choose between NGK, Bosch and Denso Iridium for my 525i M50 - what do you suggest? What plugs are the best for performance, economy, etc.?

Thanks in advance!

[jj7]

Hi all,

I can choose between NGK, Bosch and Denso Iridium for my 525i M50 - what do you suggest? What plugs are the best for performance, economy, etc.?

Thanks in advance!
Personally i prefer NGK- BKR6EK, BMW uses those....

[632 Regal]

plugs is plugs, NGK is good. Whatever you do dont use any of them so called high performance plugs or you will have problems.

[winfred]

BKR6EK NGK OR F7LDCR BOSCH will work fine

[632 Regal]

i use bosch

[kngpen]

i use bosch

Where is the cheapest place to get them?

[632 Regal]

try a local foreign autoparts, might be able to special order them from a normal parts joint too. Dont ket them talk you into ant performance plugs cause they cant get the ones you need though. Mine have been kicking for 30k so fAr

[winfred]

in a pinch i've gotten bkr6ek's from hilo o-really when we are out of our own stock, can't remember $

[tim s]

an import parts dealer for the bosch. i think dealer got me for around $5.00ea.
tim s.

[Interceptor]

plugs is plugs, NGK is good. Whatever you do dont use any of them so called high performance plugs or you will have problems.

Check this out:
http://www.denso.co.jp/PLUG/iridium-e/index.html

They do call themselves performance spark plugs, but after all, they are made in Japan, so it sounds promising - especially if you have a 4 valve per cylinder engine where spark shape and strength means a lot.

I used Denso Iridium spark plugs on my bike a few years ago and was entirely satisfied. My friend also put them in an E36 M52 320i a few months ago and says the lower rpm range has enhanced, idle is more even and that consumption is down a bit.

I want to know if any of you guys had any experience with them on your sharks. :)

I'm considering them because I ordered the EAT chip and want to maximize the performance it will give me - after all, performance chips do enhance ignition time, so I want to give my bimmer a chance to breathe with full capacity. :)

[jplacson]

After reading all this... and numerous other articles on the net... I'm wondering why Bosch Platinum4s are so horrible on the E34? Is it the way the car was tuned? Doesn't the spark plug just provide ignition? Why or what would/could possibly make the Platinums cause so much problems on our cars in particular?

Just curious. Any thoughts?

[tim]

Personally, I think the platinum acts as a catalyst, and fouls rapidly. The manufacturers claim a hotter spark, but again, how exactly does that help us when the oem's work so well. I changed my original equipment from the factory plugs at 70k, and then only because some oil started to work its way around the valve cover gasket. They were dead solid perfect. I've only heard horror stories about the platinums

I can't speak to the NGK's, but with the bosch's, you can fine tune the F7L DCR's by going up a number or down a number- F6L being a little colder, and F8L's a bit hotter. They may be hard to find though. I use Bosch and can get them easily.

[bfd]

After reading all this... and numerous other articles on the net... I'm wondering why Bosch Platinum4s are so horrible on the E34? Is it the way the car was tuned? Doesn't the spark plug just provide ignition? Why or what would/could possibly make the Platinums cause so much problems on our cars in particular?

Just curious. Any thoughts?

Here's what Brett Anderson, BMW Master Tech, says about platinum plugs:
on E34s:

"No M50 ever came with platinum plugs. BMW supplied either NGK or Bosch, nonplatinum plugs, for this engine. However, the platinum plugs are unlikely to do any damage, they are only spark plugs after all.

The problem with platinum plugs in BMW's is pretty much related to earlier
engines, and very high mileage engines. If you look at a platinum plug,
virtually no electrode is visible. This is because the electrode is
platinum and doesn't wear out. Regular plugs need to start with a decent
sized electrode to ensure it doesn't wear away too quickly.

The down side of having next to no visible electrode is that any
contamination of the plug will quickly snuff it out.

Most commonly seen in M10, M20 and M30 engines, all of which run
particularly rich at start up, is this problem of fouled platinum plugs."

He further states:

"Platinum plugs are more susceptible to flooding, not less.

Platinum plugs are more susceptible to failure in rich running engines.

Platinum plugs, once fouled, won't clean themselves like regular plugs"

With regard to M30 engines and plugs, Brett says:

"Platinum plugs are designed to last quite a bit longer than regular plugs in
a highly efficient (read Japanese) engine.

The problem with Platinum plugs in an M30, or any early BMW engine, is that
there is no exposed electrode. Only the tip is visible. One hiccup in an M30 and that exposed tip gets coated in carbon, reducing the effectiveness of the spark.

There's not an M30 on the planet that doesn't start quite rich when cold,
and burn oil to some degree. Both of these things will drastically shorten
the life of a platinum plug, hence the oft heard warning to never use them
in an early BMW."

[winfred]

over the years i've probably thrown away a couple grand in bosch platinum with all of the "good" plugs i've pitched, that gnats cock of a center electrode takes nothing to foul, ngk has a nice platinum plug with a decent sized electrode and lots of platinum on both center and ground electrodes if you must have a high priced plug