Okay Scott. I will share a few of my builds.
1. twin turbo 344 c.i. W2 heads T60 turbos (13 psi) .500 inch solid flat tappet 8.5 to 1 compression with tunnel ram and ancient Accel DFI f.i. stock 68 340 block stock 340 steel crank. 150 passes with no breakage = 911RWHP 890 ft/lb. Ran 8.68@168 at LACR (2900 feet) in a 3000 pound car.
2. twin turbo 360 c.i. stock block cast crank stock rods with TRW pistons 7.823 to 1 comp same cam as above with stock proted J heads single carb 750 cfm two T04s (10 psi) and air to air intercooler. 10.33 @ 133 in a 3517 pound Duster. Spun a rod bearing after turbo grenaded and sent garbage throughout oiling system. Full on street car with 2.76 gears.
3. 360 c.i stock block cast crank stock rods with JE forged pistons. 11.17 to 1 with ported J heads and Ultradyne nitrous cam .557/.540 246/240 duration 114 lobe seperation 750 holley 150 shot NOS cheater set on kill (over 200 to the tires) for tune up. Car had a low gear 904 with a 10 inch converter and 4.56 gears 8000 out the back door 10.90 128 @ Vegas in the heat. Weight 3440 pounds. Spun a rod bearing after 500 passes still no block issues. (Car in my avatar) with 10k street miles and yes on the highway with 4.56s. No problems.
We did kill a few head gaskets early on in build number one but it was due to detonation. EVen then no block breakage even though we were hammering on it.