duragg Posted May 22, 2011 Share Posted May 22, 2011 Anybody have an FSM for a 1977 280z, in the EM section what does it show for Valve Length specification? More specifically: I have an N42 head in my lap with steel valve seats and 116.5mm Intake valve length 117.5mm Exhaust valve length. Only FSM I have is a 1975 and a 1976. Those two FSMs spec Intake valve length at 114.9 to 115.5, Exhaust 115.7 to 116. Hoping the 1977 FSM shows different values which Cant find the 77 FSM online. Thanks, TJ Quote Link to comment Share on other sites More sharing options...
z-ya Posted May 23, 2011 Share Posted May 23, 2011 (edited) Anybody have an FSM for a 1977 280z, in the EM section what does it show for Valve Length specification? More specifically: I have an N42 head in my lap with steel valve seats and 116.5mm Intake valve length 117.5mm Exhaust valve length. Only FSM I have is a 1975 and a 1976. Those two FSMs spec Intake valve length at 114.9 to 115.5, Exhaust 115.7 to 116. Hoping the 1977 FSM shows different values which Cant find the 77 FSM online. Thanks, TJ All E31, E88, N42 and N47 heads have the same length valves. The P79 and P90 have shorter valves (intake 113.1, exhaust 113.9). Where and how are you measuring length? Edited May 23, 2011 by z-ya Quote Link to comment Share on other sites More sharing options...
duragg Posted May 23, 2011 Author Share Posted May 23, 2011 Valves are removed from the head and using a digital caliper I measure from the base of the head to the top of the tip. They are all 116.5 and 117.5. My malfunction is the 1975 and 1976 FSM say the valves should be 114.9 to 115.5 Intake, and 115.7 to 116 exhaust. Question is, are their different lengths used in different years of the N42 head. Thanks in advance for taking the time to help straighten me out. Tj Quote Link to comment Share on other sites More sharing options...
duragg Posted May 23, 2011 Author Share Posted May 23, 2011 It is possible that the 116.5 and 117.5 valves I found in this N42 head are the incorrect part. E88 spec is the 116.5 and 117.5 lengths N42 spec is the 114.9 to 115.5 and 115.7 to 116 Quote Link to comment Share on other sites More sharing options...
duragg Posted May 23, 2011 Author Share Posted May 23, 2011 Z-Ya, your question: "Where and how are you measuring length" was the answer. Incorrectly I was measuring total length and indeed the older FSMs list a spec for Total length. But they also have a drawing showing the correct measurement. The newer FSMS and the drawings of where to measure show from the base of the lapped mating surface to the tip which accounts for my rookie error. Case closed. Thank you. Quote Link to comment Share on other sites More sharing options...
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