Is there such a thing as not enough resistance when it comes to spark plug wires? I checked the stock wires to the MSD wires I have and the stockers had 475 ohms while the MSD had 45 ohms. That's 10 times less resistance for the MSD wires. I read an article in Sport Truck that basically said the factory is doing a better job on parts. That's why they're seeing less performance increases when they install an intake or exhaust on truck for tech articles in the magazine. Do you think the factory actually sees what the right amount of resistance should be for a particular engine based on it's tuning? Does the ECM monitor the spark and can it tell if a spark is to hot and retard the timing or someting? Just wondering. God, I got to much time on my hands! <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />
Jim <img border="0" alt="[cheers]" title="" src="graemlins/gr_cheers.gif" />

 

The ignition systems are so good on these cars/trucks that I don't think it matters what wires you put on there. IMHO Plus they're only like a foot long.

I changed my dads plugs and wires at around 120,000 miles?(it was alot of miles) and the old wires actually showed the same resistance as the new GM replacement ones. I can't remember what it was now. The plugs looked good still also. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> We thought the old plugs and wires may be causing his lower gas mileage but, the new ones made no difference.

I would say that GM is definately using some better parts than in the past. Did I mention he still has the stock brake pads after 150,000 miles on his '99 2500HD. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" alt="[worship]" title="" src="graemlins/gr_hail.gif" />

I don't think the computer is advanced enough to monitor the spark although I've been wrong in the past. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

John

 

If you take those figures and divide them by 13.8 volts you should be stepping up from .02 amps stock to around .30 amps with the msd wires. That should give you a lot more fire power at the plugs for a hotter cleaner burn. P.S. Top fuel dragsters measure around 80 amps at the plugs. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

<small>[ February 06, 2003, 08:15 PM: Message edited by: JWRENCH ]</small>

 

That's why top fuel dragsters can burn the center clean outta the plugs. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> Now that's ALOT of current. <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" />

John

 

its more like comparing drinking through a straw vs drinking through a coffee stir, the coil pack is going to operate more efficently with less resistance than with more, hope this gives you a better understanding of the issue.

 

JW knows his ohms law and that's where the answer to your question lies. XLR is right when he says a fuel car can melt the exectrode off of the spark plugs, but remember that a fuel car runs DUAL PRO 40 MSD Mags. They don't use that much current in the electric chain in Texas and a Silverado ignition system doesn't even come close it. My stock plug wires were approx 750 ohms. One wire was infinity(open). The new ThunderVolt plug wires were 50 ohms. You can think of the plug wire as a load because it becomes a load if it has HIGH resistance. The plug is supposed to be the load NOT the plug wire. Lower resistance means lower load and MORE CURRENT to the spark plug where it should be.

 

Guys, I understand about the less ohms, the bigger the spark and the better the burn. What I'm asking is if the new computers in cars and trucks are sifisticated enough to monitor cylinder temp and know that a bigger spark is being delivered. Are a new ECM program designed to look at cylinder temp or exhaust temp? Are they designed for a certain size or hotness of spark? If the cylinder or exhaust temp is to hot, would the ECM try and correct it by retarding the timing or something. Is the knock retard part of this?
Jim

 

Y2K - I don't think the computers are that sophisticated in these car/trucks yet. They don't have any sensors that would let them know any of that info. The knock sensors monitor for certain frequencies in the engine to determine whether there is knock and if so the computer pulls timing.

As far as the plug wires. I just don't think they make that much difference UNLESS you need a more powerful spark(like in a boosted, high compression, or nitrous application) For a stock engine they're more for engine bay decoration than anything.IMHO <img border="0" title="" alt="[Razz]" src="gr_images/icons/tongue.gif" /> <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />

John

 

Y2K, In another post you talked about installing your LT1 fans, someone said you found the wiring stuff at autozone, what kit did you ask for? I went today as I am preparing to install a set and the guy behind the counter just couldn't understand what it was I was asking for,imagine that! Anyway I appreciate any help. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by schultzb65:
<strong> Y2K, In another post you talked about installing your LT1 fans, someone said you found the wiring stuff at autozone, what kit did you ask for? I went today as I am preparing to install a set and the guy behind the counter just couldn't understand what it was I was asking for,imagine that! Anyway I appreciate any help. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Same thing happened to me. They told me they did not carry them. I went to O'Reillys to get.