Hello, my name is Mark, I recently had a new intake manifold and Holley carb put in my 84 Z28, a couple months ago. Been having what I thought were choke and idle issues, until today. From cold start I hold the gas in for a couple seconds and it starts. It will idle at 1000 rpms and slowly makes it to 1500. When I start moving it chugs for a bit and then we are good. Today things changed. Was out made a couple stops not totaling more than 5 miles, went to start after 3rd stop and engine wouldn't turn over, after several minutes and a couple tries it did start. Didn't over think it, had to get gas thought that might have been it. got to gas station and filled. It would not start again to the point of needing a jump. While getting jump, which took a while noticed the fuel filter was not full of gas, even after we got her started. Was kind of little more than a drooling look. made it home, shut her off and would not start immediately after shutting off. went in hours later and she started no problem didn't even touch the gas stood out side and turned key fired right up, fuel filter full of gas. So, is this a fuel pump issue or fuel line?

Mark

 

Does your Holley carb have clear sight bowls? If so remove the air cleaner and jostle the car from the side to see if fuel visibly sloshes in the fuel bowls. If you can't see fuel pull a lower fuel bowl bolt to see if the bowls are dry/almost empty or completely over full but use a cup or rags and CAUTION if the engine is hot to catch the fuel.

If you have fuel pull some spark plugs next to see if they are fouled.

What fuel pump are you using mechanical or electric and does it have a return? You could be having vapor lock.

It could also be a possible ignition problem but until you rule out some easier stuff.

 

Do you have an electric fuel pump, a mechanical fuel pump, or both? Do you have a fuel pressure regulator? Have you made any changes to the fuel line routing?

Many of the early cars had both an electric pusher pump and a mechanical pump. If the pusher stopped, the mechanical might be a) having a hard time pulling that fuel through the electric pump or b) be suffering from vapor lock.