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plug wire opinions

843 Views 4 Replies 2 Participants Last post by  HoosierBuddy
I've been considering an upgrade to a Flame Thrower coil and new plug wires. What are the advantages to 8mm wires over 7mm wires (I understand less resistance) as far as actual performance? Will I be able to tell a difference?


1965 convertible "White Pony", my own lesson in mechanical humility
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I went to a flame thrower coil, 8mm wires and a Petronix ignition. Better running setup but not sure if the wires alone made a difference. Plugs seem to burn cleaner and better with this setup. Good Luck. Brad
if ur going for the bigger = better kinda thing then at jegs u can get 11 mm wires from crane cams, and if u do get those wires, let me know how it turns out.
For a street driven vehicle, the 7mm are fine. I have 7mm on my daughter's '69 302, and 8mm on my '66 289. They both work just fine (very similar setup on each). I'd suggest NOT buying the Pertronix wires if you have headers. They're good wires, but have a straight plug boot. I have them on my '66 and it's just about impossible to keep the boot off of a couple of the header tubes.

If you always do what you've always done,
You'll always get what you've always got

I considered the flamethower wires too. I think that would be a good choice. Another route you might consider is shown here. I have the Ford Racing 40KV coil (which is probably exactly the same other than the finish), the Ford Racing big distributor cap & rotor that uses the newer "spark plug style" posts, and Ford Motorsports 9 mm wire set (it does have the 45 degree boots). This is the set they sell for 5.0 or 5.7 engines. The wires even have cylinder numbers on them, which might make them more difficult to cross sometime down the road. I've had the Pertronix unit in my stock coil for some time now.

Just another option.

Good luck with whatever you decide.


'65 Convertible (with many mods.)
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