Righto. Got my bog standard a12 running like a dream the last couple of weeks. Took it out for a run a while ago and it was running fine right until I decided to give it a thrash. Didnt make any funny noises, revs would have been up around the redline. Speedo said 80mph (everything on the car is completely standard).

However when it came time for me to put my foot on the accelerator again, I noticed it had a hell of a miss and wasn't happy with me at all. Pouring black smoke (running rich) and hardly wannts to go at all.

Havedone a compression test and all cylinders were fine. New Plugs, leads, changed the carby, changed the dizzy, and it still runs like a dog. She idles beautiful but as soon as it comes under load it bogs down. Timing is spot on too. WHAT ELSE CAN IT BE???????

Condesor or points??

Thats the next thing mate.. Am going to try one of those electronic ignition kits

.

Yeah will replace condenser and points.. other than that I have no bloody idea what it could be

Pertronics make a very good easy to fit electonic ignition system
I have it in my coupe for 7 years now.

have you tried revving on neutral or is it only under load it misses?
do you have resistor or non resistor compatible coil setup?

Out of curiously did you check the coil, per chance does it get hot?

Check the float level as well; it may point to the problem. Things like clogged fuel filter or bad fuel pump would cause an issue under load. My 720 pickup once clogged the filter on the way to work, was fine one second and then it wouldn't take more than 1/8 throttle.

As you already changed the dizzy in theory that would elmintate the points being it but of course who's to say the points in that distributor are good.

fuel lines could have fungus, mine did when I bought her
as she sat for 5 or more years without getting started.
Once the fuel lines where cleaned the higher rpm range
was possible rather than just idle perfect etc.

I had an issue on my 1200 where it would play up after a thrashing.

For me it turned out to be a sticky float needle.

Fuel level should be half way up the window in the standard carb.

For me, i had inconsistent fuel levels, sometimes empty and other times completley full.

Long shot, but thought id pipe up with a similar issue i had.