MGC XBY 272F
The engine was not running smoothly for a C , so checks revealed high temperatures on 3 and 6 , running very lean. Compression and leak down checks done all ok, head changed just incase it had cracks common nowadays no change.
During the build I had changed the manifold , one thing I had not checked was the fuel drain ports on the manifold , I had plugged them on the old manifold but had not done on this new one ,an oversight!! . These holes normally they have a very small capillary tube from them and they are on inlet to 3 and 6.
Plugged, the engine is running well , a colour tune was used to get a carb setup.