Its amazing Dart rates their SHP block at 600 horse the the GM blocks with stock caps are better then a Dart,
Over 38 years of building einges we sure have seen guys have problems with their blocks when getting over 500 horse with stock cap blocks unless it had the 2482 caps on them.
We do install splayed caps on quite a few of the older blocks but they have to pass a sonic test before andy thing is done.