Black Smoke on Acceleration

[zorin]

Hi

I have a '79 Targa with 3.2 Litre engine on carbs. I notice black smoke at full throttle. I also noticed that every one of spark plugs have sign of uneven burn on them: one half of every plug looks much cleaner than the other half (no deposit).

Any explanations for these symptoms?

Thanks

[john walker's workshop]

try bigger air corrector jets. that will lean out the top end. what size carbs, what jets, emulsion tubes and venturis?

[zorin]

Thanks John.
I have 36 mm vents and on the main jets I see the number 55. That's all the info I have.