In my humble opinion (and it's exactly that, just an opinion), it sounds like your 230 is running lean. Holley accelerator pumps are notorious for being sensitive to backfires, and it may be that your accelerator pump needs to be replaced. Check to see if you're getting a good shot of gas when you open the throttle. If that's ok, then you might need slightly larger main jets in the carb. You might want to check your fuel pump for output too. If the fuel pump diaphragm is cracked or torn, you'll only be getting a dribble of gas up to the carb. Put a fuel pressure gauge in the fuel line between the pump and carb; you should be getting 5-7 psi of fuel pressure with the engine running. If it's lower than that, you have a fuel pump problem. Could also be a clogged fuel line or fuel filter. Whatever is happening, it sounds like your engine is starved for fuel.
