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Thread: Difference between 7mm and 8mm spark plug wires

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    Default Difference between 7mm and 8mm spark plug wires

    What is the difference between 7mm spark plug wires and 8mm? 7mm is the factory size, and Ive read on here recently that 8.5 is too big without an upgraded ignition system. I was just curious because I have read on here that everyone uses 8mm, so I went to several stores around here to get the 8mm ones and no body carries them, they have to order them in. I was just wanting to know the difference before I have anyone order them or I buy the 7mm ones. Thanks
    My daily driver, 14x3 open element filter, shorty headers, cat-delete, magnaflow y-pipe, 3 inch pipe from y-pipe back to spintech 6000 pro street series muffler

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    grapejuice1998's Avatar
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    The difference is 1mm. You can thank me later.


    BTW-I use the 7mm Mopar wires on my 408. They work great!
    Alan Short
    D.R.T.C. #15


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    y2krtaf's Avatar
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    Quote Originally Posted by grapejuice1998 View Post
    The difference is 1mm. You can thank me later.


    BTW-I use the 7mm Mopar wires on my 408. They work great!
    LOL

    Ya beat me to it!

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    LOL ok, I figured that much, I was just wondering if there really is an advantage to them. Thanks for the super easy answer lol
    My daily driver, 14x3 open element filter, shorty headers, cat-delete, magnaflow y-pipe, 3 inch pipe from y-pipe back to spintech 6000 pro street series muffler

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    I'd think the resistance per foot is more important than the diameter of the wire.

    For what it's worth, I really like the firecore 50s, and won't buy another brand wire again. Great fit, they feel good in my hand, and you can feel them "click" into place and there's no question on whiter they're on or not, plus I know the owner, Rick. Great guy, awesome customer service, and he's a mopar guy too. Owns a rare 71 GTX w a factory sunroof option. And he's right here in Ohio. Stop by his trailer at Carlisle, Nats and other races, Rick will offer you a beer, shoot the bull, and flat out take care of you.
    --Tom



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    Quote Originally Posted by 70Cuda383 View Post
    For what it's worth, I really like the firecore 50s, and won't buy another brand wire again. Great fit, they feel good in my hand, and you can feel them "click" into place and there's no question on whiter they're on or not.
    Plus he makes them a tad longer so wire looms can be used for a clean look.
    If you haven't lived for something, you'll die for nothing.

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    Firecore 50s FTW!
    11.27 @ 118.23
    Stock and EPA approved

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    I could never get that asshole at Firecore to build me a set of wires.
    Alan Short
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    Quote Originally Posted by grapejuice1998 View Post
    I could never get that asshole at Firecore to build me a set of wires.
    That's nuts, I have two sets....When was the last time you tried?
    11.27 @ 118.23
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    Quote Originally Posted by Adobedude View Post
    That's nuts, I have two sets....When was the last time you tried?
    I called back in Feb when you gave me his number. He said he was totally out of wire, but would keep my number and call me when he got a new supply. He called about 9:PM on a Sunday night in May, but I didn't recognize the area code, so I let it go to voice mail. He left a message that I should call him immediately to give him my CC and he would ship them. I didn't call until the next day..and the day after and the day after that, but he never answered the phone and he never returned my call. So...fuck him.
    Alan Short
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    Quote Originally Posted by grapejuice1998 View Post
    I could never get that asshole at Firecore to build me a set of wires.
    I had to bitch and moan to get mine. But worth it.
    If you haven't lived for something, you'll die for nothing.

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    Sorry to hear that. He was busy early thus year, and February is probably the worst time of the year to try to order a set, because all the racers ate placing their last minute orders to get ready for the upcoming season.

    Rick is a good guy, down to earth, and will make things right when you give him a chance.

    He's also a first responder. He's a firefighter and works crazy hours sometimes, and is a family man with little ones running around. Ive had good luck sending him an email or PM on moparts (sunroofGTX) to tell him I'm placing an order and then use his website to make payment.

    I too, ran into the "I'm out of stock" issue in early march, but ordered anyway. I joked about paying extra to go to the top of the waiting list... He said he already had guys doing that! I paid normal price and said "ship them when you got them, no rush" and I had wires in hand about 4 weeks later.
    --Tom



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    Guess I was lucky...Had mine in a couple days.
    11.27 @ 118.23
    Stock and EPA approved

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    I agree that he was a nice guy on the phone, but he didn't do right by me so I'll stick with what I can get.
    Alan Short
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    Not meaning to high jack the thread but since we talkin about ignition. What is a good spark plug to go with? I still have the factory stuff on there with 215 000kms on them. I'm thinkin bout changing the plugs and wondering if I should just go with the stock ones or if there's better stuff out there. thanks
    1999 Dakota R/T, 3" spintech exhaust

    1983 Dodge Ramcharger 360 4bbl, 4 speed, Dual dynomax exhaust, Edelbrock carb 600cfm, Mopar performance ignition, 4 inch skyjacker lift, Rancho shocks, steering stabilizer, 35's, Mickey Thompson rims

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    Quote Originally Posted by 360magRT View Post
    Not meaning to high jack the thread but since we talkin about ignition. What is a good spark plug to go with? I still have the factory stuff on there with 215 000kms on them. I'm thinkin bout changing the plugs and wondering if I should just go with the stock ones or if there's better stuff out there. thanks
    You will get 100 answers, from the simple and cheap, to the complex and expensive. Everyone has their pet spark plug. However, the stock Champion plug is awesome. I believe it's RC12LC4.
    Alan Short
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    I run an autolite 3922with nitrous or 3923 for the street


    Forged 408 12.10 @ 111mph under the knife again

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    Stock type Projected tip, good for at least 1* less ignition advance needed when compared to the older style non projected tips. Comparing the two, less advance equals less negative work put on the piston as it comes up to top dead center on the compression stroke.
    The Dakota RT is gone... but not forgotten.

    '15 Granite Crystal Metallic SRT 392.

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    Quote Originally Posted by Intense RT View Post
    Stock type Projected tip, good for at least 1* less ignition advance needed when compared to the older style non projected tips. Comparing the two, less advance equals less negative work put on the piston as it comes up to top dead center on the compression stroke.
    Fuck your smart.

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    Quote Originally Posted by Adobedude View Post
    Guess I was lucky...Had mine in a couple days.
    Sell me your second set of firecores!

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    Quote Originally Posted by BluRT00 View Post
    Fuck your smart.
    You're.
    Alan Short
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    Nope, I think he was saying fuck YOUR smart, like, fuck you for knowing

    As in, he's jealous thst you know something he doesn't.
    --Tom



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    Quote Originally Posted by 70Cuda383 View Post
    Nope, I think he was saying fuck YOUR smart, like, fuck you for knowing

    As in, he's jealous thst you know something he doesn't.
    LOL bingo! Guys like a mad scientist, I've seen his notes from the engine I bought.

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    Quote Originally Posted by BluRT00 View Post
    Fuck your smart.
    Lol


    The Dakota RT is gone... but not forgotten.

    '15 Granite Crystal Metallic SRT 392.

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