1984 Chevy 350 still being a headache to get running right

[Ken Ford]

Super hard to diagnose without seeing it.

That is true, but we just want to give the OP a direction or two to pursue a diagnosis.

 

[Ken Ford]

yep low compression heads with dished pistons yield about 8 to 1 compression..at around 150/170 Hp but would have to check heads and block VIN

Yeah and when they get “weak”(wore out) it seems to be more pronounced. Start with about 175hp and lose a bunch as it ages...

 

[Gunny Jake]

How’s the cooling system? If the cooling system needs to be drained and flushed it can cause these symptoms. We had an ‘85 with the same symptoms. Replaced a bunch of the same things you listed and the symptoms didn’t go away. We disconnected the battery for a few days, Replaced fuses and relays and Drained and flushed the cooling system and heater core and refilled. The truck ran great from then on. Good Luck and Please let us know what the magic fix finally is.

 

[Red Rex]

Are your spark plug gaps.035? If so try .045. Incorrect gaps will reduce manifold vacuum and adversely affect performance. Last try replacing the accelerator pump in the carb. Alcohol in today’s fuels degrade rubber parts

 

[8675309]

that motor looks passed around caressed by bubba hand
swap it out