So my 76 corvette has been sitting for a while now. I have turned her on and ran her to temperature a few times in the driveway but today was the real road test. She shifts fine all 3 gears but at 2500 plus RMP she stutters and losses power and jerks. I ran her home at 55 mph at about 2500 rpm and she ran just fine. But if I tryed to push it past. It won’t let me. Fights me all the way. I know the basics fuel, spark, and air. I am thinking fuel filter or carb. Just asking for some advise
How long has it been sitting? Odds are the gasoline has gone stale.
I’ve seen stale gas a few times that was so bad that it would not ignite when a match was thrown into it.
Another possibility is that the carb secondaries are not working correctly. Those can be affected by choke operation.
Do you use gas that contains ethanol?
I’d guess ethanol in modern fuels has melted parts in the fuel tank, lines, filter or carb. Rebuild time!, New filter, maybe new fuel pump and you might seriously consider new fuel lines compatible with ethanol laced gasoline.