Sent you a PM, Mr. Johnny from BluePrint. I'll await your reply. Thanks for joining the forum!
Just a quick update here, Been working with Crusty junker here on some diagnosis, Nice guy, and want to help him pinpoint his problem. As noted this is just a blueprint short block, so its a bit hard to pinpoint issues that involve so many other MFG's parts, but we're trying!!!
Some common things to note (in relation to any of our engines, not necessarily to crustys situation)
Aluminum heads require better than OEM intake/head gaskets. Felpro or cometic or similar designed for aluminum heads are recommended if you're putting aluminum heads on one of our short blocks.
Do not use synthetic oil during break in: its slicker than standard oil, and can wear the cross hatch off the cyl walls before the rings seat
on aftermarket aluminum heads, be sure to thread seal the rocker studs if they are through-bolts. the engine can suck oil past rocker studs.
obviously the TBI engines the OP asked about are long blocks with cast heads, but wanted to toss some of this out there for others coming across the thread, or interested in a short block.