A cap is just that a cap.
If you were to change distributors and coil that would make a difference.

I'm sure you meant from 6mm to 9mm wire.

6 Gauge wire would be about 1/4" thick.
1 or 2 gauge being like battery cable


Dennis https://www.ford-trucks.com/user_gallery/sizeimage.php?&photoid=1733&.jpg
[i][font color=red]Calgary,Alberta,Canada[/font][i]





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78 F-150 429CJ,Silver, Explorer Pkg.
641/2-Mustang 260,Pre-World's Fair Car.
64-Fairlane500 S/C waiting for a 390-4spd.
68-Mustang 289-Sunlit Gold 80,892Mi
78-Buick LeSabre 403 4V
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