Ok guys I am in need of some help here. My AWM motor has 246,000 miles on it and just started rattling. I planned on rebuilding the engine with stock bearings and rings but with IE RODS and also planned on replacing the oil pump considering it had only 12-14lbs of oil pressure at idle! The car was parked as soon as it started rattling. Now I've pulled the engine and pulled three and four main bearings and noticed there's wear on the bearings and noticeable only visually wear on the crank itself! I cannon feel the wear on the crank at all and can't catch anything as I run my fingernail across it! I planned on doing a whole frankenturbo kit build with the engine rebuild but now worried I'm gonna have to get my crank turned! My question is what the rule of thumb when it comes to needing to get your crank turned? I posted a pic of what my crank looks like if you can see it!

 

Rule One - use a micrometer! At best your fingernail can only tell you whether there are any ridges or scratches, which means the journals need to be ground. I've found in the past that mains can be in very good condition, while big ends can be totally buggered. There is only one good check, and that is to measure the journals with a micrometer, and compare them against the manufactured specs. Particularly if you are going to play with extra power. That motor has a lot on the clock, and any extra power will show up any weaknesses lurking in the background. Loud bangs when under load are usually a little disheartening, not to mention expensive. They can ruin a bit more than your day!