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Pinking is a sort of hi-ish knocking noise, bit like a diesel on start up. It means that the engine is firing a bit too early - too much advance probably.
Either check the timing using a timing light or BODGE!
Mark the position of the distributor using paint or scratchy mark (for reference purposes)
Slacken the dizzy clamp bolt and rotate the body anti-clockwise a bit (about 1 - 2mm)
Test drive and try hard acceleration in 3rd from 20mph ish
Repeat 2 & 3 until pinking noise just stops
If your noise continues to the point where you have turned the dizzy so far that the car won't start, then it probably isn't pinking! so re-align to the marks made in step 1.
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