i have a 305 in a 84 el camino. i put a new intake and carb on. i think its a 650cfm carb. it runs great, but if i leave it sit for more than like 10 minutes, after driving it for awhile, and go to start it back up. it acts like its flooded and i get a lot of black carbon smoke out of the exhaust when it does finally fire up. is this too big of a carb or?? it runs great other than that. also it has a streight pipe going all the way back. i get a lot of black carbon smoke?? anyone have any suggestions?