I have a 68 barracuda convertible 318 with edelbrock 650. The carb is new and was running fine once I installed and tuned it everything was good for a week or so. I took the car out for a going to town ride and ran great for about 30 minutes into town then stopped at a store for a few minutes then went to start it back up and the battery was dead. Jumped it got it started and it was running fine again. I was headed home and got to an intersection and left the light pretty hard and went a few hundred feet and i suddenly lost power it would go but basically like in limp mode like a modern car very little power from no throttle to full throttle didn't make hardly any difference. I got the car home but it was a long ride. it would get up to 40 50 mph but took a while. So after this i figured it was a couple things so i replaced alt, vr and plugs and wires. Nothing seems to help the fact that when the car is cold it will fire up and rev fine but once the car gets to operating temp it has this issue. Now if i put it in gear with very little throttle like a few percent it will act like it's fine but within a second or two it bogs and goes into "limp mode" for lack of a better term. Now when this happens if i pump the throttle "engine off" i get very little to no fuel from the squirters. It will start and idle but when i rev it just sounds almost like a 4 cylinder. I've gone through several fuel filters because of sediment in the lines. But a new filter doesn't seem to fix it as it still does it once warmed up. Any ideas.

 

Do you have points or electronic ignition?

 

Electronic. I also put ethanol gas in it. So i'm thinking it's vapor locking in the fp.

 

When it is in “4 cylinder mode” spray some gas into the carb primaries, if the rpm comes up and runs better than fuel is your problem. If you’ve seen sediment come through it may have a clogged pick up or reduced internal size fuel line. When they get this old replacing the complete system is needed as cleaning or blowing through may just have the problem reoccur later at the worst time.

 

I will need to try that. I did just replace the combination steel and rubber hose that ran from the fuel pump to the carb not it's 95% steel with just the rubber hose connecting to the carb. The previous owner did replace the tank and lines a few years back. I'm going to clean the carb really good and try again.