Misfiring - take 2

[Jez Arnold <jez@xxxxxxxxxxxxxx>]

A while ago I posted a problem I had with my 1976 GT 1600 Junior with a 2
litre engine. Chris Brown sagely pointed out that I had fitted the old
shorter 1600 carb stay and changing this for the 2l stay fixed part of my
problem ie no more petrol fumes in the cabin. It also seemed to fix the
misfire for a while, but it has steadily returned. The engine misfires
badly when it hits 3000 rpm in any gear. I've tried just about everything
to fix it with no joy. Could a stuck advance mechanism cause it? How can I
test for this?
Any ideas or thoughts will be greatly appreciated. Thanks in advance.

Jez Arnold
jez@domain.elided
1976 GT 1600 Junior
1988 Sprint Veloce 1.7

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