[Mr Jody]

Originally Posted by talos

I'm not to the point of access to this yet. I think you mean, by the pic of this url. Ford 352, 390, 406, 427 and 428 Engine BlocksThe drilled passages to feed the lifters. I guess there is not other way with any numbers?

Yes, in the picture in the link you provided, those are the lifter oil galleries that must be drilled for hydraulic lifters. As for other numbers, look at the third picture in your link. Note that the block is upside down, oil pan and filter adapter removed in that picture, but that casting date is still accessible with all that in place, just more difficult to see. That date code will provide at least somewhat of an indication of what to expect to see when you get to look at the rear of the engine. I have some information that indicates for 427 blocks, if it is 1967 or earlier, then it is probably not drilled for hydraulic lifters, 1968 or later and it just may be. Or if it is a service block it may be drilled.

Don’t let the sentence above the pictures confuse you, which states

The one exception was the 352 High Performance engine of 1960 which was equipped with mechanical lifters and not drilled for hydraulics.

That sentence is referring specifically to the 352 cubic inch FE engine. Note that as the caption under the first picture states

Nearly all "FE" blocks have this "352" in the casting at the front of the block, including the 427s.

So seeing that “352” on your block really doesn’t mean anything for your purposes. I have a 390 block with the “352” on the block, and hydraulic lifters.

As Brent says, the only way to be sure is to see the two bosses above the cam bearings as indicated in the picture. But the block casting date may at least may give you an indication of what you may have, and a glimmer of hope if you are wanting to go the hydraulic route.