It seems I may have stirred up a bit of a "sh**storm", with my well intentioned CAUTION post originally ?
That was not my intent, however, given subsequent responses, and the prevalence of similar experiences from others finding this Inferior Block Hardware and the Main Stud "Failures" @ Load, I would like to clarify a few things.

* I took issue, with the Mating of genuine ARP Nuts, to NON-ARP Studs in the Block as delivered from World Products.
I, like others on here it seems, find this "questionable" product practise ?

* I also take issue to references from a World Representative, of Foreign made Torque Wrenchs as being an "Unfair", but nonetheless STATED, potential cause for the Stud Failures ?

* Lastly, I am somewhat peeved with further references that World "Engineers"?, have determined "those studs to be of sufficient quality".

In Response to the above;
I will be shipping all the Studs in question, which I feel are defective, for a complete Mettallurgical Analysis, both Destructive Tensile & Non-D, Rockwell, etc., etc., full spectrum.

I am lucky enough to be located Geographically in the Oil & Gas Capital of North America, with some of the most reknowned Industrial Engineering Infrastructure & Testing Facilities in North America close by.
They Test "metals & fasteners" all the time, on everything from Blow-out prevention Fasteners to Sour Gas Well Hardware.
Remember the recent Gulf Oil Spill Fiasco ?
We produce more Oil here in 1 Day, than that entire LEAK spilled in the Gulf!

My point being,
stay tuned,
I WILL have a Full Report on the Studs, and their compliance with any "known" Industrial Standards ASAP.
It will some take time, I will report back when completed.

Personally, If this had to go beyond my original CAUTION post, I would have sincerely hoped, and expected, that World Products would have stepped up, and indicated knowledge of a "suspected" supply chain management problem involving Wrong Main Stud hardware, and asked for imput from those affected for some kind of remediation effort ?
Just Good Business in my opinion only.

I sincerely hope, that the Stud Analysis when completed, is NOT akin to a rating of the Cheapest poor quality fasteners available, and NON Compliant with any "known" Industrial Technical Grading ?
THAT, would sincerely compromise any Findings by World "Engineers" of Fastener suitability ?

I Thank You for your time, and apologize to this Boards Onwers, for using up valuable Bandwidth, on what should have been a NO BRAINER Caution report.