I personally would prefer a bolt to snap due to overtorquing rather than threads getting stripped or other damage occurring to the block.  The remains of a bolt that snaps can usually be unscrewed.  Stripping requires thread repair.
With stainless, everything will probably be fine but there is always a risk of thread galling.  When that happens, drilling out the remains is required and retapping may be required.  Also be aware that not all stainless is equal and the stuff at a typical hardware store is probably the lowest grade of stainless available.  ARP sell really good quality stainless and you can find other options at an industrial supply, although you will probably have to buy that hardware by the box, rather than only the quantity you need.

Bottom line, if you want the most trouble free, use zinc plated steel hardware.  The 23-28 ftlbs spec does fall in line with grade 5 hardware.



Lawrenceville, GA

It occurs that what applies to the stainless available at big-box home stores (cheapest grade) likely also would apply to their base level zinc-plated steel.  So, I’ll use the grade 5.

6 VOLTS/POS. GRD. NW INDIANA

For the most part grade 5 is overkill in an automotive setting that is not suspension or stress related. Intakes, water pumps, PS mounts, AC dist hold down, oil pan etc need only the lower rating of a 2. I use 5’s also and clean all threads, male or female, but I know it’s not necessary. 

56 Vic, B'Ville 200 MPH Club Member, So Cal.

A vendor named Totally Stainless has stainless bolts that they say is equal to grade 8.  They sell by the piece.


54 Victoria 312;  48 Ford Conv 302, 56 Bird 312
Forever Ford
Midland Park, NJ

Update: So took everything off the front, removed he broken bolt which was sticking out of the block and I was able to remove it by hand. Added new gaskets and bolts. Re-assembled and fired up today. No leaks. Will cool and check again tomorrow. Glad it is all back together. Thanks for all of your help.