hi there i have a 68 tbird with the 429. i have a holley 750 cfm double pumper carb on it and ats been fine for 6 months until now. the car seems to run out of fuel / fuel starvation even though there's fuel in the pipes and the carb etc. nothing seems to be blocked and the pump is working . i have been told to check the fuel tank breather pipe but i cannot locate this and i cant tell what it looks like. also i have been told that the coil could be breaking down - patronix electric ignition thing . the car smells very rich when it packs up and it begins to missfire and run very lumpy before it seems to run out of fuel. any help guys

Sounds more like the car is flooding.

Also do you get black smoke from the tailpipe when this happens?

well it does smell rich when it happens and start to smoke - this morning started her up and loads of grey smoke came out the tail pipes. also there seems to be a fair bit of exhaust smoke coming out of the breathers on top of the engine - more than usual. she cut out this morning and i pulled her over, she did not want to run - just like when your running out of fuel and then she was fine after revvingthe engine hard for a bit. ????? really strange. im thinking of trying a new coil,plug leads and plugs then go from there .

First thing you may have your oil dilluted with gas if it's running that rich, Smell your dip stick. If you think the oil is dilluted do not run the engine. Change the oil because you'll ruin the engine in a hurry.

http://www.network54.com/Forum/74182/
Also try this forum Sounds like a Carb problem to me

well i fixed it ! firstly i checked the ignition side - put new plugs and leads on her then i bought i racing electric fuel pump but still this was no good - lastly i removed the fuel tank - found all sorts in it , plasic bits or something, some burnt matches and even a bit of money !!! lol so now she's all back together now - basicly a brand new fuel system's on her now - holley 740 cfm carb,new electric pump, patronix ignition setup,new plugs and leads - she goes very well now very very fast