Yes, #0996 may be used for cleaning Holley carburetors, but they must not be soaked for extended periods of time. We suggest soaking them no more than 4 hours in order to protect chromate coating. If the carbs are especially dirty, you might consider either purchasing our Professional Chem-Dip (part #0905) or first spraying them down with B-12 Chemtool Carburetor, Choke & Throttle Body Cleaner (parts #0113, #0117, and #0120) in order to shorten the soak time in #0996.