Spark plug resistance?
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From: Normal, IL
02 E55; 99 CLK430 (Sold)
Spark plug resistance?
First off, I was told this a few months ago so I've been accepting this as fact seeing as how he seemed to know what he was talking about. Here's what I'm talking about.
Now on to my question. I finally ordered wires from magnecor. I'm a little confused and maybe even a little worried. Basically I asked the guy at Magnecor what kind of resistance was in their wires. He said very minimal. I told him I wanted to keep the resistance at 5K and our cars took a non-resistor plug. He basically said I probably wasn't right and just said something to the effect of most cars use a resistor plug so just put whatever plug it tells you to put in there and use our wires and you'll be fine. I don't like that answer at all. I figured maybe I would just go ahead and buy the FR8 so I had the 5K resistance.
Anyway, can anyone shed more light on this? I admit I don't know enough about it and I'm taking reitmeid's (the user that posted this in the first place on the other forum) word for it as he seemed to know what he was talking about. Basically, I want to do this right so my car runs as it's supposed to.
How is the Bosch double platinum better than the Autolite double platinum? I think the main thing to remember is keep the resistance at 5k. My 430 came with bosch F8dpp332 . That is a non-resistor plug. The resistance is in the plug wire connector. I often see FR8dpp332 listed for the 430 . That would double the resistance to 10k. If you are going to use performance wires see if they have ends with resistors built in. If they don't, use FR8dpp332 or any other decent resistor plug to keep resistance at 5k. If your replacement wires are resistor wires, use the F8dpp332. Like Josh K. said in some post, use any good non-resistor plug, even a straight copper. I like $2 denso copper u-grooves. Just keep the resistance factory.
Anyway, can anyone shed more light on this? I admit I don't know enough about it and I'm taking reitmeid's (the user that posted this in the first place on the other forum) word for it as he seemed to know what he was talking about. Basically, I want to do this right so my car runs as it's supposed to.
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From: SCV SoCal
2002 CLK430
Placing a resistor either within the spark plug or the wire suppresses radio frequency interference. Without a resistor in the plugs or the wire, the radio frequency interference will make the radio sound horrible and can cause misfires. This is the type of misfire that may take several hours of diagnostics before the wrench figures out what’s wrong. The misfires occur because the racket also interferes with the ECU. Rumor has it that exposing an ECU to long term radio frequency interference is one way to melt one down. I can neither confirm nor deny this. On the other side of that coin, someone can use resistor wires AND resistor plugs. That combination will result in a spark with reduced energy levels. The consequence of ongoing low energy sparks? The incomplete combustion will reduce both fuel economy and power, shorten plug life, and possibly cause the cats to die sooner rather than later. Even though this combo won't kill the ECU, I’d pick one or the other – resistors in the plug or the wires. Let me correct that, I’d pick resistors in the wires. That way I wouldn’t have to worry about having disabled something the PhDs at Bosch assumed would be present in the ignition system. The dual plug ignition in the M113 is complex. I'm guessing it has a high speed talkback system to tell the ECU when the first plug has fired so that it can know when to fire the second plug while in staggered fire mode. I wouldn't want to do something to get in the way.
Since you've bought non-resistor wires, you may want to buy resistor plugs. Lastly, in this particular instance, the Magnacore tech is wrong.
Since you've bought non-resistor wires, you may want to buy resistor plugs. Lastly, in this particular instance, the Magnacore tech is wrong.
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From: Normal, IL
02 E55; 99 CLK430 (Sold)
I understand. Basically what Magnecor was saying is that their wires suppress radio frequency without the resistance....at least that's the way I understood him to say. If you have time, could you look at their website? I'm sure you'll understand it a whole lot better from them than from me. Then possibly tell me what plug to go with? Thanks Marcus.....
http://www.magnecor.com/magnecor1/main.htm
http://www.magnecor.com/magnecor1/main.htm
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From: Normal, IL
02 E55; 99 CLK430 (Sold)
The 8mm set. I only have the Powerchip for my ECU and amg airbox from the 55 on my 430. I'm also debating on pulleys. Anyway, I wanted a performance set but there really was no need (in my opinion) for the 8.5 race ones.
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From: SCV SoCal
2002 CLK430
If those are the Magnecore Electrosports 80 cables, then they claim to suppress RFI. You can determine whether they do pretty easily. If you have the OEM plugs on your car, simply swap the cables, start the car, and turn on the radio. If you hear tons of static that ordinarily isn’t there, and that static disappears the second you turn the car off, then you’ll need resistor plugs. You can perform this test with only half the cables replaced (the passenger side is easier to do). If you need resistor plugs, I’d buy Bosch FR8DPP332’s. If you don’t hear any static, then you won’t need resistor plugs. In that case I’d buy Bosch F8DPP332’s.
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02 E55; 99 CLK430 (Sold)
Good point. I always just figured I'd replace the wires when I replace the plugs but I guess there's no rule that says I have to do it all at the same time. Thanks again Marcus.
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02 E55; 99 CLK430 (Sold)
Marcus (or anyone else),
Maybe you can give me a little bit of help just one last time. I finally ordered the F8DPP332 Bosch plugs. What I actually received though is the Bosch FR8DPP33. I called their customer service and they had absolutely no clue what I was talking about. Horrible customer service actually. Anyway, getting back to the point, I am under the assumption the the FR is a resistor plug while the F is the non-resistor plug I really want. Should I just go ahead and use these anyway with the Magnecor wires or return them and keep hunting for the plug I need. I have a feeling Bosch replaced all of the plugs I wanted with this new plug. Any thoughts?
Maybe you can give me a little bit of help just one last time. I finally ordered the F8DPP332 Bosch plugs. What I actually received though is the Bosch FR8DPP33. I called their customer service and they had absolutely no clue what I was talking about. Horrible customer service actually. Anyway, getting back to the point, I am under the assumption the the FR is a resistor plug while the F is the non-resistor plug I really want. Should I just go ahead and use these anyway with the Magnecor wires or return them and keep hunting for the plug I need. I have a feeling Bosch replaced all of the plugs I wanted with this new plug. Any thoughts?
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From: SCV SoCal
2002 CLK430
(360)863.0557 has F8DPP332's. So does dub-dub-dub dot alloemautoparts dot com. Both for about 50% of list price. If the dealer (who sells them for a lot closer to list) and wholesalers can get them, then they're probably still being produced. I'd use the OEM plug.
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From: Normal, IL
02 E55; 99 CLK430 (Sold)
Thanks. Just as a heads up for anyone else thinking of buying the plugs, here's where I bought them from. The description clearly says the correct plug but they still sent the wrong ones.
http://replacement.autopartswarehous...20Plug&dp=true
http://replacement.autopartswarehous...20Plug&dp=true
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From: Normal, IL
02 E55; 99 CLK430 (Sold)
Interesting. After doing a little more research, Bosch is saying that's the correct part for our car. They don't even list the non resistor plug anymore. I wonder why they made the switch. Doesn't seem to make sense to me.
