Bosch Silber replacements for W8LCR Spark Plugs?

[blakersE30]

Hi,

Time for new plugs for my '89 E30/M20.

After reading a bunch o' boards, I'm interested in using Bosch Silbers ...

Stock plugs are copper-core W8LCRs.

Is there an equivalent/swappable/recommended Silber to use here? AFAIK, there's no such thing as a "W8LS" ...

If I use another plug, what's the right gap for it then ... still the 0.28?

Thanks,

Richard

[wludavid]

I don't know the answers to your questions, but why did you choose Silbers over stock? Or am I just any idiot and they are one of the many OEM varieties that the E30s shipped with?

David

[Jared at Pelican Parts]

Dont think you are going to see any difference with Silbers over the Coppers. I always reccommend the stock W8LCR every time

Whatever you do, dont run the Platinums. M20's dont like those...

[blakersE30]

> wludavid
> I don't know the answers to your questions, but
> why did you choose Silbers over stock? Or am I
> just any idiot and they are one of the many OEM
> varieties that the E30s shipped with?

> Jared at Pelican Parts
> Dont think you are going to see any difference
> with Silbers over the Coppers. I always
> reccommend the stock W8LCR every time

Well, if anybody's the 'idiot', it's me for "listening" to the endless threads on all the "other" boards ... ;-)

There are MANY comments of the following ilk:

"Silbers are much preferred / the best, but if you can't find 'em" (nobody seems to be able to) "use the Supers" (which again raises the question, which ones!?)

> Whatever you do, dont run the Platinums. M20's dont like those...

THIS is a VERY consistent comment. I've never found a legitimate/understandable "WHY", but "Everyone" seems to say the same ...

Sooooooo, my question remains --

IF i'm going to remain 'stubborn' and choose a Silber for this application,

(a) which one will work/fit ?
(b) what's the appropriate gap ?

Any further LOGIC as to "copper vs super vs silber vs platinum" would also be appreciated ... it seems too much like Voodoo to me =)

richard

[wludavid]

My theory is, in case of voodoo, go with cheap.

Except speaker cables - lots of voodoo there, but I have experience firsthand, and the the higher quality ones do generally sound better.

As a rule of thumb, unless you have real proof or *lots* of anecdotal evidence, go with stock replacements.

As for a little logic, you might know this, but copper and silver are the two most common types of conductor. Silver is marginally better than copper, but a lot more expensive. Audiophile speaker cables are sometimes made of silver, but only ones that are super-expensive (like $1000/foot). From what I understand about sparl plugs, it isn't about the most voltage, it's about the right voltage, so increasing the voltage to the tip can change the spark timing - if two gaps spark plug gaps are the same, the one with higher voltage may spark sooner, since it takes time for transient voltage to build up before it jumps the gap (creates a spark). I'll have to check some references about that, but I'm pretty sure that's how it works.

To recap - I'd say go with stock plugs.

[Jared at Pelican Parts]

The Platinum plug has an electrode that is shielded by an insulator that almost completely covers it. It is extremely easy for the plug to foul out this way. It's not a matter of the conductivity of the metal, but the electrode design. The early Platinum plugs were supposedly very good, but you really wont find them anywhere, and if you did, they are VERY expensive.


Often times, I have seen cars that run poor, run like new by removing the Platinums and putting in Coppers which are the same thing as Supers, FYI...

I HIGHLY doubt you will see any difference whatsoever with the Silbers. Just run the Coppers and you will be fine. You dont need to upgrade the ignition system on the E30. The motronic system is just about as good as you are going to get.

My car has headers, Custom programmed engine management software, Ford Mustang 5.0 fuel injectors, 535i air flow sensor, higher fuel pressure and a custom air scoop. I run the stock copper plugs, I have NEVER had a problem..

[jase007]

I also run the stock copper plugs (207,xxx miles) and with / without chip, intake and Remus exhaust the car has performed flawlessly. The one time it didn't ... was when I bit on the platimun plug BS.

Jason

[blakersE30]

ok, "SOLD!" on the Coppers.

Thanks for the insights all!

Jared, I note that you have the 535 MAF installed ... in an E30?

If so, any thoughts/guidance/URLs on the DIY approach to MAF upgrade, vs. the SplitSec commercial version? Other than the obvious, cost ... I'm mainly "worried" abt the associated electronics required to make it all work, not so much the hardware install.

It may well be that THAT's been discussed elsewhere on this fourm ... if so, a URL pointer please?

Thanks,

Richard

[Jared at Pelican Parts]

Cant point you anywhere..

I just put the elctrics of the 325i in the 535i unit. Used 5.0L injectors and bumped the fuel pressure up a bit... Gives you a little better throttle response, thats all. I had a chip burned by a buddy who knows how to manipulate them. Not really worth doing, actually. Maybe got 5HP if that...

Im actually not running it anymore..