what is the correct spark plug gap for a '74 dart with everything stock and a 1 bbl barb. i have a 2.5 exhaust if that makes a difference.

0.035" if you're running stock Chrysler electronic ignition.
0.045" if you're running HEI, MSD or BYOB.

When I ws a kid, BYOB meant 'bring your own booze '. What does it mean now? You can experiment with spark plug gap, and see how it runs with other settings. You might be able to stretch that .035 stock setting out to .040 and see an improvement in fuel economy, or throttle response. The gap gets bigger with time, as part of the electrode burns away, so if you go bigger, you might need to check it more frequently.

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69 Dart Swinger, 230 ci slant, t-5 five speed, intercooled turbo, 4 wheel disk brakes, tubular upper control arms.

I think in this case it means "facetious".

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I've been calling it as i see it for my entire life and that's not about to change. Take it or leave it.