Quote Originally Posted by hpwdboss1
I've been gathering parts for my 460 and now have 2 pair of dove-c heads.
One pair is chalk marked 429, the other pair have had the engine tag wired to them marked 460 71. The ones marked as 429 have no air injection holes into the exhaust and have the "dove" lettering positioned so the bottom of the letters are toward the exhaust manifold side of the heads. The heads with the 460 tag have the air injection ports and the "dove" letters are upside down as compared to the 429 heads. When you set the heads side by side on a table,deck down, the valve cover gasket sealing surface on the 429 head is nearly 1/4" higher than the same point on the 460. If you measure down thru the head bolt holes, the 429 heads are .045" taller than the 460. I can't c.c. the chambers yet, but they appear to be identical. My question is, are these heads off of blocks with different deck heights, maybe made with different deck thicknesses, or have they been milled that much or what's the story? The intake surface looks to be the same height relative to the deck,so maybe the same intake will fit on both.
Short of one pair being drilled for Thermactor (smog pump) exhaust and the other set being non-drilled, all 4 heads are identical in regards to bolt-to-fit dimensions. The orientation of the lettering in the heads means nothing. All 429 & 460's used the same cylinder heads over the years that they were simultaneously in production and are therefore fully interchangable from one engine to the other, and this includes any pair of heads from one carburetted 429/460 to another regardless of year. It may be possible that the heads tagged as "460" have been decked before. On these heads, .010 of decking equates to about 2-3cc less combustion chamber volume. There is a triangular detent on the cylinder head's mating surface, dead-center, spark plug side of the cyliner head mating surface. Compare the depth of this feature between the two pairs of heads and I'll bet the "460" heads measure less than the 429 heads...should be about a .100" deep step, less if radically milled.

Paul