Beaten to death, but I'm confused abour spark plugs

I just spent the past hour searching through old archives, and I read a lot about how I shouldnt use platinum plugs.

the only reason I found was that the little tips can break up and fubar up the engine.

I also read something about resistance. But I'm not sure if the post was saying that plugs with buil-in resistance are good or bad.

The plugs I had before the plainums were Bsch Super R6 082

are these copper? There is a big surface area at the end, so i'm thinking it is. But the thing is that these plugs only lasted a short while, and when I was trying to figure out what was wrong with the car, I kinda canclled them out b/c they had been replaced recently.

I just need to know what I should put in the '70 280SL

TIA

[Mark DiSilvestro]

The general consensus is that platium plugs aren't for older Mercedes (or even some newer ones) What I've heard is that the tiny tips require a higher firing voltage and are more easily fouled. That said, I've been running Bosch platinums in my 1972 250 / 2.8-6cyl for several years. However, my 250, unlike your SL, has an electronic ignition with a, supposedly, hotter coil. If you changed back to the standard plugs and it runs OK, I'd stick with them.

Happy Motoring, Mark

[Gilly]

I'm in the "resistance" camp. The plug wire ends have resistors built into them, so you don't want/need resistor spark plugs. Typically the plat spark plugs are resistor plugs. Other than the resistance factor I have no problem with platinum spark plugs.
Gilly

Is this built-in resistance contained in the big boot part of the wires? My wires looked really bad, so i replaced them with a set I picked up at Autozone. I had to cut them to size and i'm pretty sure they dont have built in resistance. That said, now that I dont have resistance in the wires, will the platinum plugs be ok?

[Mark DiSilvestro]

Typically, the resistance is built into the wire TIPS that fasten to the plugs and at the cap and coil. Hope this helps.

Mark

[Gilly]

It's your call, I imagine it would be fine.
Gilly

so now I guess the only issue is the surface area of the plug heads?

[autozen]

Rad-Man,
You and many others worry too much.In my opinion your biggest mistake was buying some junk from Autozone unless it was Bosch or Behru.Save yourself a lot of grief and get an OEM set of wires.Next step is to get a set of non resistor NGK plugs. Yes, I said Japanese. I use them exclusively as do most other Mercedes facilities here in California.They are exceptional.I know we're weird out here,but then again who sets the trend for the rest of the world? Don't get me wrong:I have a top of the line BOSCH dish washer and a BOSCH vacuum cleaner,but then again spark plugs are a different matter.


peter

[DANTRCAV]

Go with Peters advice.

Get the "real" wire set so that you have the correct resistence in the plug boot ends. Get the NGK plugs.

NGK BP6ES are the equiv of Bosch W7DC

BP5ES are one step hotter.

Been using them in my 250C for 4 years.

My experience here, however; as "they" say "your mileage may vary"

Dan

hey guys- I ended up purchasing the OEM wires and W7DC plugs off of this site, but I put them on and the plugs still fouled! I have pretty much given up. Here is a link with more detail...

Ignition problems... Why has my engine fouled 3 different sets of plugs!

[DANTRCAV]

I just checked your referenced post.

I have a 250C so I have carbs (two Webbers) so I can't speak for the FI. As the other thread discussed, either your car is running way to rich due to any number of problems or there is a problem with the ignition. Your mention of the "coil booster" might be a clue.

My 250C ran poorly until I replaced the stock carbs with the Webbers. Then it ran good but I was plagued with plug fouling problems (even using NGK plugs). I was cleaning the plugs twice a week (about every 150 or so miles).

I replaced the stock ignition system with an electronic (Crane) system and replaced the stock coil with a Crane coil at the same time. No more plug fouling and the car ran even better.

Not saying you need to replace the ignition system; but at this point I would certainly at least take a look at the coil and, if you have it on your car, the Transistor Control Unit. Might just bite the bullet and find a good local MB tech. He can check all of the components that could cause this problem.

My .02.

Dan

BAHHHH!!! NO WAY! I run these in my Jeep, and I hate them. Well maybe not blind hatred, but I will never buy them again. First of all, I thought everyone here says platinums in the old MB is a no-no. On top of that, the only good thing about the 4 electrode design is the long life. And for 6 bucks a pop, you can change out a regular platinums 5 times at the same cost.

AND, I upgradded my coil and wires in the jeep, and i wanted to increse the gap of the plug for a bigger spark. but the +4's are fixed. stupid...


Here's what the jeep world thinks about these plugs..
http://forums.jeepsunlimited.com/ubb/Forum36/HTML/004111.html

[Deltacom]

Originally posted by rad-man
hey guys- I ended up purchasing the OEM wires and W7DC plugs off of this site, but I put them on and the plugs still fouled! I have pretty much given up. Here is a link with more detail...

Ignition problems... Why has my engine fouled 3 different sets of plugs!

Rad-Man,

When the fouling of plugs is sorted out, try Super-4. You wouldnt want anything else!!