Thanks for the comments!
Car was running badly, #2 was missing most of the time, plugs were black
The carb is a weber 28/36 DCD, really simple carb, actually feels like its too simple as no control over anything apart from an idle screw
There is an insulation plate under it, it was a thin plate and was not looking too good, looked to have gone brittle, so got a new plate, which is about double the thickness. That is now fitted with new gaskets.
Also got a service kit for the carb and fitted it, cleaned all jets etc
Checked leads were in correct order
Fitted new points, condensor and distributor cap and set points gap
Fitted new coil (didn't know history of the old one)
At this point, it wouldn't even start
Did the carb work and it starts every time now, but still running poor. Also, revs increase after a minute or so of running, up to around 1500, then it drops off and stops
When I had it running sort of OK, I managed to get timing light on it and set to 4 deg's before TDC
I've swapped plugs and leads between #1 and #2 and problem stays witrh #2
Did a compression test, all at around 155 with #2 at 140
Plugs are always black, dry soot black, which is suggesting running rich
I need to check the valve clearances yet
What other carbs are used on the 1565 engine? I assume I have the standard manifold? (will add pictures off my phone later)
Thanks
Tony