Car appreciation... the aesthetics, the engineering, etc

what carb? Early SU (HS4) carb? screw the big nut on the jet (under the body) up a tiny bit to raise the fuel level
A common enough problem with them
If that doesn't sort it try a slightly richer needle, but once you start with that you will be messing about forever

Im not exactly sure what carb it is, 1986 red hot model. Its already running quite rich I think as it crackles and pops on the over run but that might be due to it having a straight through exhaust