C5AE-A Block

[chris401]

May be trading for a block I have not seen yet. IF this block has the undrilled cross bolt bosses will it have the thick cores also?
Thanks

[chris401]

Looks like that was a tough question for a 1 year block. No cross bolt bossed or webbing but it did take a 7/32 drill bit on one bank. It being a March casting it only had a few days left in production.

[machoneman]

Cool!
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I brought a 15/64" drillbit to the last swap meet.
 July 9 2002, 6:55 PM 

I've selected a 15/64" drill bit as my basis for determining whether a block is a 360/390/410 candidate or a 406/428 candidate.

 All six core plugs should be popped out of the block. Probing all reachable spaces between the cylinders, the drill bit shank (the non-fluted and non-flatted portion) should NOT fit between the cylinders at any location, high, low, or in between. If it does, there is too much water gap between cylinders, and not enough metal for a comfy (sturdy) bore out to factory 428 numbers.

 If the drill bit does NOT fit, this means there is likely enough material to bore to 428 values but you've still got to sonic map the cylinders to verify core shift isn't creating thin sections in the cylinder.

 This drill bit value may eventually change as more is learned, but for now 15/64" what I use.

Dave Shoe.