Spark plug wires?

carguy300

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I want to change plug wires and plugs on my 300. It has 2 different type wires but both are 7mm. I want to upgrade, has already been converted to electronic with orange ECU. What is best wires and plugs for my motor? Ive been looking at Taylor or Accel from summit. not sure about wire resistance. Would 8mm be better? Whats a Good plug?
 

Davea Lux

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I want to change plug wires and plugs on my 300. It has 2 different type wires but both are 7mm. I want to upgrade, has already been converted to electronic with orange ECU. What is best wires and plugs for my motor? Ive been looking at Taylor or Accel from summit. not sure about wire resistance. Would 8mm be better? Whats a Good plug?

For my money, the original champion J-11y plugs are still the best. These cars ran fine with the factory style plug wires which were 7mm. If you converted to MSD ignition you will need 8mm wires. The 8mm wires are better insulated and carry the higher voltage from a high output coil better, otherwise you don't need them.

Dave
 

carguy300

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I still like champions myself. Wasnt sure with electronic if 8mm wires would be better or not. Its been a Long time that owned a car i could actually work on myself, didnt know how technology has changed. So many choices now. Appreciate you Dave.
 

Davea Lux

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I still like champions myself. Wasnt sure with electronic if 8mm wires would be better or not. Its been a Long time that owned a car i could actually work on myself, didnt know how technology has changed. So many choices now. Appreciate you Dave.

The new champion number is RJ-11yC when you can find them.

Dave
 

CBODY67

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For a reasonably stock motor, no real need for the 8mm wires. They were popular back when high-output ignitions were deemed "needed". But as time progressed, even the OEMs stopped using them. Before I went back to OEM wires on my '70 Monaco, I tried some Taylor wires, but they still had the carbon-core-style conductor, so the real difference in them and stock was the coating on the conductor, plus the distinctive plug boots. Some might differ, but I like the BWD (formerly Borg-Warner Cool Wire) magnetic suppression wires for the particular application (already terminated). Less total resistance than the carbon core wires and very long lasting.

Plugs are another area which can have many opinions. I used to religiously use Champion plugs in the stock heat range. Then discovered that equivalent Motorcraft plugs lasted longer and ran just as well. Then I discovered the NGK V-Power plugs, which worked a bit better due to their gap design. Then went to the newer NGK Iridiums. Gap in the .040" range, for good measure.

IF accessibility to the plugs is an issue, but you don't drive the car very much, then what you need is a basic spark plug of the correct heat range. BUT if you plan on driving the car a lot or it's a pain to get to the plugs, the much more durable Iridiums can be the best choice (at least 100K mile durability).

The factory spec gap is .035", but the old Mopar Perf Race Manual advised that with a sufficient powerful ignition system, there is no need for more than .060" gap. So to me, going to .040" gap range is a little bit better than stock. The wider gap allows more of the mixture to be exposed to the spark. Which is related to a key design component of the NGK V-Power plugs.

Personally, I like things which have a stock OEM look, but are better than what the car came with. Just me. If you like the colors of the aftermarket wires, your judgment call.

Enjoy!
CBODY67
 

carguy300

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I want to keep under hood looking right also. My brother runs NGK in his 65 300 with 413, he seems to like them.
 

Davea Lux

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Thanks. Who makes good plug wires these days?
I want to keep under hood looking right also. My brother runs NGK in his 65 300 with 413, he seems to like them.

Those are also a very good plug. The factory wires were black on you 300. MSD and Accel both make good 8mm wires. Belden makes a good lower cost wire.

Dave
 

carguy300

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I like the black wires, can tolerate blue ones, but dont believe i can do orange or red.
 

CanCritter

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am gona reroute my wires differently to hide them as much as l can....whats a good set to to get if you wana customize your own lengths?
 

James Romano

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I have 8mm Blue Taylor's on mine with an Accel (tan) cap. I'm disappointed in the overall length of my wires as they stated 383, but they are at least 4 inches too long on almost every wire. They work great, I don't have any issues with performance, but then again, I'm not racing or hammering on the motor much. I like to cruise.

I had to change mine out in a pinch as I really wanted to drive the car for the final months of the season and just wanted to get a good, low cost set on there for the time being. The Taylor's have very good reviews, and are priced very well.

For plugs.. Bosch Platinums. I've used them in every car I've owned since the 90's. They're reliable, and do the job without issue. Again.. but I don't beat the hell out of my cars.

In the Spring, I'll switch up to the black 7mm wires, just to get it OEM as I've spent much of the Winter cleaning up and putting my engine bay back to stock look.

As for wire "management"... take your time, and do it right. It really makes a difference in the overall look of your engine. Nothing worse than opening up a hood... everything is clean and organized... but your wires are all over the place.

Don't mind the wire-tied power steering line... I'm in the middle of changing my front shocks and mud flaps.

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cbarge

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I run repop date coded plug wires with orange box and Champion plugs on the BoaB.
Very happy with the wires. Have instructions showing which wire goes to what cylinder. I used plug wire sheathing or boots on the rear plug wires to avoid burning.
I had NGK plugs at first but the boab's 383 fouled them up. After some fine tuning I used NOS Chsmpions that happened to be a better heat range that fitted my engine with the mods it has.
I run an Accell Super Stock coil but painted black to look stock.
Tan Mopar cap on a Summit recurved electronic distributor.

On the 66 300 it has Pertronix conversion with matching wires.
The Pertronix wires are so-so. Fitment can be tight and had trouble with one of rhe terminals at the distibutor cap end.
Being a stock motor it runs NGK plugs.

On the small blocks of our fleet we run Neihoff or Taylor wires with NGK plugs and Mallory Blaster coil.
If running headers on small blocks, Taylor wires are a must but i order two sets 1 straight set and 1 90 degree set. I mix them together to cleat the primary pipes.

Bottom line use what will work for your motor. Stock or slightly warmed up engines 7mm wires work and fit fine.
Hope this helps
 

CBODY67

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When looking for OEM-style replacement wire sets, you'll discover a few differences in models and model years for the same engine application. Somewhere in the BWD wire online catalog, it has graphics to detail each wire set. Distributor boot ends, spark plug boot ends, AND lengths for each wire. Which can help with fitment issues. The same brand wires, wit the same part number for the set, a few years apart in purchase date, can have some differences in what's in the box. An extra inch in the wire length, or different boot/insulator colors. But with some attention, then all work. And, of course, the routing changes usually had different wire supports to go along with them.

Enjoy!
CBODY67
 

cbarge

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I agree with CBody 67.
Onmy car 6 wires have 90 degree boots and the rear plugs have 135 degree boots.
When I converted the Boab to 2bbl to 4Bbl HP I had to change the valve covers and wire looms to accomodate the HP logs and to look "factory correct".
Boab is far from original and her 383 is far from stock---but looks the part..
boab 2018 005.JPG

boab 2018 006.JPG
 

James Romano

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What is a Boab? I really like how tight that engine bay is! Looks great! No pie tin? That would look great on that dual snorkel.
 

USSMOPAR

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If you look in the larger Mopar forums you will find Firecore spark plug wires are rated at the top. Many reports of improved performance on what already was a finely tuned engine using MSD and other's wires. There really is a difference between the FC and the rest. Custom lengths available from FC as well so there will be no fitment issues.
 
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