i can appreciate full thread engagement, but bottoming the bolt is worse than having a few threads short. if you have a thread or two more engagement than the bolt diameter, that is all it needs.
Here is a rule of thumb that you cant go wrong with 1 X thread diameter in steel 1.5 X thread diameter in cast, bronze etc. 2 X thread diameter in aluminum Any more than that is of little gain (fastener will usually break first) any less and dramatically reduces strength and threads will pull.
correct. i was just using the example for steel because it was a flexplate/converter application. as for aluminum, if possible, i like helicoils [or variations thereof] or studs, still using the 2 times thread diameter.
