Need a mechanical historian

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Mar 4, 2008 | 07:22 PM

acct21

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Need a mechanical historian

Anybody recall the approximate duration (at 0.05) of the stock, late 70's 400 cam, as it may have appeared in the 1978 Bronco?

Mar 4, 2008 | 09:25 PM

dlburch

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Joined: Jul 2005

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From: Kansas

Does this help?

http://www.engineparts.com/motorhead...pecs/ford.html

Mar 4, 2008 | 09:58 PM

hollenjoe

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wow that numbers are agresive for a 400 stock camshatf......with the stock 8.6:1 comp and that type of stock cams they never got to 6.5 dcr... no wonder....

Mar 5, 2008 | 08:25 AM

acct21

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I'm not sure I believe the the values for the "700" camshaft. First off, most sources, including Crane Cams' tech support, say the stock valve springs bind at (or before) .490" lift. Second, Ford had at least three 400 camshafts in 1979, and none of them approach that .490" lift.

http://home.earthlink.net/~bubbaf250/parts/parts03.html

Scroll down to camshafts.

I'm looking for the .050 lift durations on the 1978 Bronco 400 cam, D4AE-6250-A. Maybe someone with omnipotent cam knowledge can extrapolate that from the lift and valve opening/closing events.