Chevrolet Repair: Possible Fuel System Issue, chevy c10, power valve

Question
Hello Tom, you helped me before with my 84 Chevy C10 acceleration/timing issue. I ended up switching out the Carb for edelbrock and it has been running really good up until the last few days. I notice now that during 1st gear on take off and in reverse the truck seems like it is not getting enough fuel or something. It hesitates and is very sluggish the most in those gears but second and on it screams and shifts just fine. Also it starts up every morning no problem, but after a few starts throughout the day, it takes around four seconds for it to turn over. Seems as if after the fuel system is primed it takes longer for it to crank over. It idles great now and my timing issue is gone. When I replaced the carb I also replaced the timing chain, starter, alternator, fuel filter and spark plugs. I know its getting fuel to the carb because when I look into the carb both of jets squirt fuel. And I inspected the fuel filter and when I took off the hoses on both ends there was stored fuel in it so I don't know at this point.. Bad fuel pump maybe?  Any thoughts? Thanks!!

Answer
HI RYAN, TO ME THIS SOUNDS LIKE A FAULTY ACCELERATOR PUMP ISSUE OR POWER VALVE IN CARB. GET A FLASH LIGHT AND OPEN THE THROTTLE SLOW AND STEADY,MAKE SURE BOTH JETS ARE SPRAYING FUEL FROM THE AIR HORN..YOU WANT TO SEE A PERFECT FLOW OF FUEL HERE.NOT OF AND ON.IF SO I THINK ACCL PUMP ISSUES.THIS IS A LONG SHOT BUT ARE YOU SURE THE TIMING IS GOOD.TRY TO ADVANCE IT JUST A LITTLE BIT OR UNTILL IT PINGS,THEN BACK IT DOWN JUST A TOUCH. TIMING CAN CAUSE THIS AS WELL. AS FAR AS THE LONG CRANK WHEN WARM THIS MAYBE A COIL ISSUE.I HAVE SEEN MANY COILS WHEN WARMED UP THEY DONT HAVE THAT GOOD ZAP UNTILL UP AND RUNNING,JUST A THOUGHT.I DO NOT FEEL YOU HAVE A FUEL PUMP PROBLEM AT ALL. A FAULTY PUMP WOULD HAVE LOW POWER ON THE OPEN ROAD AND WHEN YOU NAIL IT. YOU SAY IT RUNS GOOD LIKE THIS...LET ME KNOW HOW THIS WORKS OUT FOR YOU AND WHEN YOU LEAVE THIS SITE COULD YOU PLEASE RATE THIS ANSWER.THANK YOU,, TOM.