In my chumpvette. Around 3000RPM the car will start to fall flat. By 4000 RPM it goes away and car pulls strong. Only happens about 50% of the time.

I've changed:
Fuel Pump
Ignition
Opti
Plugs
Injectors

What's the minimum diameter fuel line I need for the car? Its a stock LT1 but I'm fueling it through the stock fuel line that ran the anemic L83 that was previously installed.

Gonna run a leak down/compression test next weekend.

Any suggestions would be greatly appreciated.

 

I would check tps for a dead spot.