Can a 1994 Chevy K1500 350 5.7L with TBI 220 switch to Holly 670cfm without changing the fuel pump?
No, the stock fuel pump in the 1994 Chevy K1500 350 5.7L TBI 220 engine will likely not be able to support a Holley 670 CFM carburetor. The stock pump is designed for a much lower fuel demand than the Holley 670 CFM carburetor. To ensure proper fuel delivery and performance, you will need to upgrade to a higher-performance fuel pump.