Head bolt Re-Torquing

I never re torque my 340 but I did not use to steel shim, still don't think it matter..in fact the steel will less likely compress and lose torque

I did blow a head gasket once going flat out and it turns out the other head bolts were not at 80 or more lbs, more like 50 it felt like....but I did not build that engine so don't know how tight they were from day one, it did last many years and miles before blowing out

Oh how the white smoke poured out on the freeway from the exhaust, I believe everybody who seen me thought my engine was done in. I replaced the gasket and was back on the road in 2 days, lol....lucky I didn't hydo lock the piston, I drove it 5 miles home like that cause me too thought the motor was done