Hot Rods Spark plug wires.

I just did a tune up on my '46 Ford, 350 Chevy powered Woodie. I replaced the plugs and all the MSD 8.5mm wires, rotor and cap. My friend stopped by while I was doing the job and told me he hasn't replaced his plug wires in the 20 years that he has owned his car. How often do you guy's replace your spark plug wires, do you change them by age or miles?

 

Went through my car in 2022 before BTT50's. Figured on replacing the Accel wires since they'd been on there since it was built 42 years before. Put a set of Taylors on it, 2 of them didn't last a year in the exact same places where the Accel's had been. Another set of Accel's on it now.

 

I just replaced the plug wires a few days ago because I replaced the distributor with a new one that has those male posts on the distributor cap. Not pleased with trying to get long enough plug wires since I am running a SBC and like running them under the exhaust. Hate the look of plug wires over the valve covers.

 

My '51, with a Mallory dual point is still running what I believe are the original plug wires. They were on the car when got it in 1987 and looked original on a car with 61K verified miles. When I installed the Mallory in 2016, I reused them because they still looked good. They are solid core wires, which I believe should last forever if they aren't damaged. I do have a fresh Mallory "Flattop" with new Packard 440 wire that I am going to install because I like the looks better than the later Mallory (it has a RED distributor cap) that is in it now.

Carbon core wires? I had a '60 Dodge that literally quit running on me in about 1970. After troubleshooting it, a set of new wires (nothing else) completely solved the problem.

 

You have to replace plug wires!? The wires on my coupe have been on there since about 1967.
Most of my daily drivers the get replaced as needed, if falling apart or causing problems.

 

Had a '62 Bicayne with a stock inline 6. I had no idea how old the plug wires were but this tank was hardly worth the investment for a new set of wires. When driving in a hard rain or through standing water the splash under the hood was enough to soak the ignition. It would just shut down like you'd turned off the ignition switch.

I always kept a can of WD-40 in the car. I'd coast off to the side of the street or into a parking lot, pop the hood and spray the wires and distributor cap with WD-40. Close the hood, start the engine and drive away like nothing had happened. Got to the point where I could do this while stalled at an intersection and have it running again before the light turned green. Kind of a one-man Chinese (or Dutch or Polish or Irish) fire drill.

 

I usually replace them when they need it, which means never, for the most part. When I get an old car that's been sitting for a few decades, I make sure there are still plug wires on it, and not chewed up too much by rodents. If there's a misfire that might be due to a plug wire, I might replace that wire.

 

I just bought some for the Olds, the set on there was installed 16 years ago. They still work but I figured it was time. Besides the me in 2010 thought blue wires would look cool. What a maroon. Yellow ones coming.

 

I make my own whenever I get a car. And I don't particularly like making them. So "as needed".

 

I hate to tell you this, Billy, but I don't think that's an upgrade.

 

Years back the neighbor had an inductive plug wire checker/tester.
I had a misfire on my daily, he brought his tool over. May have been a SunPro.
It found the bad wire on the car, if I recall, he checked on the length of the wires, at one spot, ghe voltage was way higher. He said “that’s a bad wire”. Swapped it out and all was good.
I remember looking up the tool he had, at the time was over a hundred bucks, but this was pre-Amazon days.

 

Back in the late 70s, 80s if you wern't running yellow it was a sign you were a cheap ******* & still running the OEM wires, new ones in black is the current trend....

 

Like most others, I only replace them if needed. I look at the condition of the outer jacket and will perform the "in the dark arc test" if I suspect misfires.

 

who needs stinkin' plug wires! Got a 51 Ferguson tractor (not M***ey, but the real deal) that had been sitting in a field for 4+ years, nobody knew how long. Looked at wires in the garage, pieces of 'em fell off so I used some electrical tape on 'em just to see if it would run. 3 revs and it started, nary a miss! Put new ones on it, now it takes a half dozen or more turns to start. They don't make 'em like they used to.

 

Our rodents here are getting better at chewing copper.

 

I couldn't find those maroon wires you were talking about, but I did find these. Would they work?

 

I actually put a scope on the engine and look at the secondary ignition. A bad plug wire really stands out. With that said, I don't think I've replaced a plug wire in the last 20 years. When I worked at a Lincoln/Mercury dealer in the early 70's we replaced single wires on a regular basis. The parts room had single plug wires in stock by the firing order. That was in the days of carbon core wires. Again, part of a tune-up was putting a scope on the ignition.

 

I was thinking more of a rainbow of colors, do they mix and match?

 

I will go over any leads that are close to any heat (exhaust), and check that they haven't gone hard and cracked. That is the spot all the zap will come out of and go to ground. I bought a dedicated plug lead crimper and make my own. Sometimes at a swap meet I will see a complete new sets of leads (to fit anything) going real cheap, so I will buy them and modify to suit.

 

I am thinking I may have an ignition problem rather than carburetor. Spits and bucks part throttle low rpm, wot seems to be okay. Worst when cold. Been through carb 3 times, new pwr valve each time, no clogs found or dirt that I can see. Engine is 200 6L Ford, Holley 2v 350cfm, healthy cam, exhaust. Need more than a Volt meter?

 

That works good, when you have a scope. I recall the mechanic at a station I worked explain what was what.
But I think I’m in the majority of those who don’t have one to use.

 

With the quality of wires now I think you are better off leaving the old ones in until you have a problem. The ones on my daily truck were 20 years old when I sold it.

 

--and i think this plug wire replacement thing was started by dealers, some shops, etc. just to get more business. Now honestly, does granny really know that it does/does not need wires? Smooth mech..says it does, so of course it does. Another $150-200 mamm!!

 

I put some Accel wires on my car about 30 years ago, they still work fine. They're yellow but I'm not going to throw them out because of that.

 

If the wires look good and the motor is running good, why replace them?

 

I was driving the 35 year old Jap pickup on a many hundred mile trip back from our old off-grid property with the last load of junk. The beast started running on three cylinders, which wasn't quite enough on the mountainous highway.

It took me a while to figure out the dead cylinder was due to a failed spark plug lead, but with the load of junk in the back I rigged up a new lead from a piece of thick, rusty steel wire, with pieces of vacuum hose over it where it rested on the valve cover. This super temporary bodge worked great all the way back home. It worked so well that I just continued driving the truck daily, and I didn't get around to replacing it with a proper replacement wire (used, of course) for another year.

 

When I got my car it was in dire need of a tune up, so I replaced everything including wires. I suspect the next time they get changed my kid will be doing it, and I'll be in the dirt.