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[Alan Roehrich]

How much would switching the plugs change the CC's?

If you replace a standard cold spark plug with a hotter extended tip spark plug, the spark plug takes up more volume.

Quick example. Set up a small block Chevy head, and check the chamber volume with an AC R42T spark plug. Note the volume. Now, swap to an AC R45TS spark plug, and see the difference.

Now, the difference in the volume in most cases will not amount to a hill of beans performance wise, but the tech guy has a set volume, and they have to draw the line somewhere.


Alan Roehrich


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