How's it going guys? I got one that I can't seem to figure out. This is my 383 dual quad motor in my 1956 plymouth belvedere. I got it running and even drove it around the block, getting close to driving the wheels off of it! But For some reason, it seems after your give it half throttle or more, it will want to die. If you let it sit for a minute it will fire back up and I can limp it home. It also seems to run great at idle but then after about 10 minutes of running it will want to sputter out and die even if you try to give it gas. It will not start right after, but wait 5 minutes and then it will fire up again. It also seems like the motor doesn't want to go over 4,000 rpm which I think is weird. What do you guys think? Timing? carb adjustments? I played around with both but no improvement. Here is a video of it running when I got it out of the shop before my first test drive, it seems all good but during my test drive it died on me half way around the block, sat for a minute, then fired it back up and drove home. I would really like to get it ready for the mopar show at the sacramento raceway this sunday. Any advice? thanks guys!

http://youtu.be/W8yB0aNbxh0

Sounds like it's starving for fuel.... Restricted line? Short fuel pump pushrod? Bad pump? Sucking air at a bad rubber hose?

I'd wanna pin it to either ign or fuel. Can you get it to act up in your driveway while a helper sits in the dr seat waiting then when it dies you quickly pull the coil to dist secondary wire off & hold it 1/4" from ground while your helper cranks it & see it there's spark or not

Sounds like you have a fuel filter in front of your fuel pump...

I agree that it sounds fuel flow related. How old is the gas? Have the tank/lines/ or filter been cleaned/replaced?

"" But For some reason, it seems after your give it half throttle or more, it will want to die. If you let it sit for a minute it will fire back up and I can limp it home. It also seems to run great at idle but then after about 10 minutes of running it will want to sputter out and die even if you try to give it gas.""
"" It also seems like the motor doesn't want to go over 4,000 rpm which I think is weird.""

Do you have a fuel pressure guage on the car? If so, have you noted what the pressure is doing?

If your fuel pump is going bad, you don't need much pressure at idle to keep it happy, then once you start cruising then you need more demand from the pump. The pump may not be keeping up at cruising speeds and above, especially since you have two carbs to keep full.

Thank you for the replies so far, I do not have a fuel filter in front of the pump, just one after and it is new. The gas is brand new since The car was sitting for a while I drained and flushed the lines. I checked an no ki ks or bends in fuel line. I am running a stock fuel pump, I ordered a Carter 120 gph fuel pump, well see if that helps the ceil starvation issue.

is it possible your fuel is boiling away? when it stalls out do you still have fuel in the bowls?

The fact that you can't restart it right away, but it will start right up after a few minutes has me thinking it is not fuel related, but ignition, unless there is vacuum in the tank due to improper venting. If the carbs go dry you would have to crank the begeesus out of it to start again, you could pour a little gas down it's throat to make sure next time it happens. If it starts with a little gas poured in there ya go. If not it aint a fuel problem. Something is getting hot and quiting then when it cools off it works again.

Good that you don't have a filter in front of the pump to restrict it.

Maybe if you can, next time it dies, stick a timing light on one of the spark plug wires and crank the motor with the timing light trigger pulled and see if you have spark.