View Full Version : Holley 4160 power valve or valves?

05-20-2007, 10:47 PM
351 backfired - now blows black smoke & idles like a bronc. I have been told, it probably has blown the power valve. Here is the question - Does the 4160 have 1 or 2 powervalves? Looking at the Holley website (http://www.holley.com/data/TechService/Technical/4150-4160%20Exploded%20View.pdf), it appears to have 2 (primary #121 & secondary#147) but I never hear of people replacing 2 valves. Is it only the primary that needs to be replaced?
thanks for your help.

05-21-2007, 10:10 AM
It has only one power valve. Only the non-vacuum secondary carbs have two power valves, and all original equipment carbs would have vacuum-actuated secondaries.

05-22-2007, 10:10 AM
Thanks Viabill - the folks at Holley confirmed that it only has a primary power valve.