Spark Plug recommendations?
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Here's what to expect from a stock Bosch plug...
<center><img src="http://pictureposter.audiworld.com/1009/spark_plug_close_up_2.jpg"></center><p>...I too want to find another option. BTW, Bosch did nothing for me and sent me a letter stating they had received it and were studying it. That was about a year ago. F#(% Bosch.
Mike O.
Mike O.
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Yikes, he posted that on the 02 forum? well, hello more coil pack fails :)
One thing to note - since it was fun playing with ignition scopes back in the days when all cars came with spark plug wires, the larger the gap, the more voltage required to jump the spark. The fatter the electrode tip, the more voltage it is required to form the ignition arc ball. Platinum usually has a smaller tip and requires about 30% (edited) less energy than a copper plug to arc the voltage. So, with a platinum spark plug, one can run a larger gap to optimize ignition.
It's most probable that copper, with the fatter electrode can sink in more heat than the platinum or irridium counter parts. But increasing the gap from what the stock ones are set up, can mean a rash of burnt coil packs. Stock coil packs can only produce so much voltage. If they are required to produce more, they will overheat, could break, but at least before that, misfire usually starts to happen - oh so slowly though, so one better be vagging while he plays with spark - or just replace it with higher energy coil packs and gap away!
It's most probable that copper, with the fatter electrode can sink in more heat than the platinum or irridium counter parts. But increasing the gap from what the stock ones are set up, can mean a rash of burnt coil packs. Stock coil packs can only produce so much voltage. If they are required to produce more, they will overheat, could break, but at least before that, misfire usually starts to happen - oh so slowly though, so one better be vagging while he plays with spark - or just replace it with higher energy coil packs and gap away!
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conductivity
from my reading, platinum plugs use smaller electrodes to OFFSET 1) worse conductivity and 2) higher cost. they are more durable, so they also won't vaporize as quickly.
I'd like to see a reference showing 70% difference in energy to jump the same gap on a plat vs. copper plug. I'd expect the opposite qualitatively, tho' not sure at that magnitude of difference.
(not arguing with you...just trying to learn more here)
I'd like to see a reference showing 70% difference in energy to jump the same gap on a plat vs. copper plug. I'd expect the opposite qualitatively, tho' not sure at that magnitude of difference.
(not arguing with you...just trying to learn more here)
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good read
very interesting chart in this document.
i may be rethinking again. the problem for us big rich running turbo kit guys is this:
I have run the plats that apr sent and iridium IK22 (all one range cooler). That's probably safest when you're in the boost pretty hard, but for daily driving, they foul and they foul quick. i haven't discovered a way to get them to self clean easily.
These copper plugs don't look like the answer either, now. At the same heat range, I'll likely have the exact same issue shortly.
thinking out loud, I'd say it would be great to run stock heat range for daily use and swap to cooler plugs for the track to prevent fouling. The danger would be preignition if you had a spirited run on the hotter plugs.
thoughts?<ul><li><a href="http://home.att.net/~t.vago/faq-ignition.html">copper vs. platinum</a></li></ul>
i may be rethinking again. the problem for us big rich running turbo kit guys is this:
I have run the plats that apr sent and iridium IK22 (all one range cooler). That's probably safest when you're in the boost pretty hard, but for daily driving, they foul and they foul quick. i haven't discovered a way to get them to self clean easily.
These copper plugs don't look like the answer either, now. At the same heat range, I'll likely have the exact same issue shortly.
thinking out loud, I'd say it would be great to run stock heat range for daily use and swap to cooler plugs for the track to prevent fouling. The danger would be preignition if you had a spirited run on the hotter plugs.
thoughts?<ul><li><a href="http://home.att.net/~t.vago/faq-ignition.html">copper vs. platinum</a></li></ul>
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oops, I didn't mean 70% less, I meant just 70% of the amount of energy for a conventional plug...
in other words, 30% less. I'll edit above really quick ;P
I took a quick look at the chart, and without reading the whole document, I'm trying to figure out - how did he measure that? I hope it's not from a electronics multi meter that only puts out millivolts to about 3 volts depending on the range selected. If so, let me ROFL first. If not, I'm curious how he measured resistance if he has to supply thousands of volts and divide by whatever current is required to form the arc. I'll go try to find some read on their difference. It was something I did some searching a while back.
I took a quick look at the chart, and without reading the whole document, I'm trying to figure out - how did he measure that? I hope it's not from a electronics multi meter that only puts out millivolts to about 3 volts depending on the range selected. If so, let me ROFL first. If not, I'm curious how he measured resistance if he has to supply thousands of volts and divide by whatever current is required to form the arc. I'll go try to find some read on their difference. It was something I did some searching a while back.
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Re: oops, I didn't mean 70% less, I meant just 70% of the amount of energy for a conventional plug..
Tektronix makes supplies/probes and oscilloscopes to do things like that. My friend (currently in London) has a 20000 or 40000V probe, good supply, and a Tek. 'scope to go with it.
Its amazing what you can get people to trade you when you do work for them (he did some ECE work for a guy who had that stuff, its worth a few thousand dollars on the low end...).
Its amazing what you can get people to trade you when you do work for them (he did some ECE work for a guy who had that stuff, its worth a few thousand dollars on the low end...).
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Re: Here's what to expect from a stock Bosch plug...
That's so funny! I once sent in a Bosch warm-up regulator for a Porsche and they sent me the same note--"We're investigating the problem". I never heard from them again. And you know what? I never pursued it--so I guess their strategy works after all. ;-)
Aloha,
Keoni
Aloha,
Keoni
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