CLASS RACER FORUM - View Single Post - 427-425hp w/GM 401 heads

dahkahuna · 12-05-2012, 10:53 PM

what is the clarification as to what exhaust valve diameter is legal in the GM performance 401 replacement head, the head comes as a 1.88 diameter is this the legal valve size we can use in the 427-425hp engine, or do we have to use either the 1.84 or 1.72 valves? whats the answer?

12-05-2012, 10:53 PM	#1
dahkahuna Member Join Date: Jul 2006 Location: san dimas , calif Posts: 128 Likes: 0 Liked 5 Times in 3 Posts	427-425hp w/GM 401 heads what is the clarification as to what exhaust valve diameter is legal in the GM performance 401 replacement head, the head comes as a 1.88 diameter is this the legal valve size we can use in the 427-425hp engine, or do we have to use either the 1.84 or 1.72 valves? whats the answer?