I知 THINKING of installing a set of the D5AE 351W heads on this 94 351W roller short block I have. I知 not too concerned about the compression ration unless I would be dropping it considerably?? What I am really worried about is the pushrod length & geometry, anyone know what is involved when going from pedestal mount to stud mount on one of these engines? Thanks , Crossy

 

You'll also need to worry about those pressed in rocker studs too, unless they've been replaced with screw in studs.

 

Because the press in stud style heads were never combined with a roller lifter block on the 351, there was no stock length pushrod that was dedicated to that application.

You could get an adjustable pushrod and measure what you need, then probably find a commercially available pushrod by looking through a catalog that arranges them by length.

Or you could throw in the towel and get a good pair of GT40 or GT40p heads, or even the very common E7TE heads and use the stock pushrods for a 1994 351 with a roller camshaft.


The D5AE heads may not have hardened exhaust valve seats, which should be considered.

 

D5's would have had induction hardened seats same as any later head. Unleaded fuel was at the pump by then. Question is though have those seats been ground past the hardening ?
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I have read in the past that only cars and light trucks were mandated to use unleaded gasoline in 1975, so there was a possibility that bigger trucks would have unhardened seats for a few years longer.