I'm new at a fitting job. I have zero idea how plastigauge works. They just let me torque the main bearing. They don't tell the purpose of plastigauge. This videos helps a lot.
Your use of plastigage was spot on. That looks like a 3-53 Detroit main cap bolts final torque 130 ft # or 177 NM. 3-71 Detroit 184 ft # 250NM final torque. 30wt oil on threads and under heads of bolts
Was that your daughter. That was funny right there. Been about 10 years since I've used plastiguage. Works well if used correctly. Just wanted to brush up to use it on an engine I'm building. Well done......She needs a little practice though.
You would do it first with old bearings to find current oil clearances if bearing or journals aren't scored. Then with the new bearings to find oil clearances after replacement. Gives you an idea of wear length from the last bearing changeout.
IT IS NOT OKAY to leave the plastigauge in there! That is bad information and not the way to use properly. If you leave it in there it takes all the clearance out of the bearing and journal. There is no way for the journal to float in a pressurized film of oil if that crap is in there forcing what would have been the clearance over to one side. Take a guess what happens the first few crankshaft rotations before that crap blows out of the bearings and you have metal to metal contact in there? You literally do not want metal to metal contact in your bearings, ever! And you are forcing it to do exactly that on initial start up. Plastigauge works fine for what it is, but it needs to be removed and cleaned before final assembly.
No "professional" should be using Plasti Crap. You should have the correct tools. And no way that was 290 foot pounds! Barely more than hand tight. Inch pounds maybe.
