generally speaking, how long does it take for the "cross-hatching" to wear off the cylinder walls. I know there are alot of factors involved with it but I am just looking for a guestimate.

 

i've saw "high milage" engines and you could still see the cross hatch pattern. was it still effective? i doubt it? what are you really asking?

 

well, I just got a LT-1 from a yard and I'm trying to determine the approx. milage on it, I pulled the valve covers and oil pan and just judging by looks it doesn't have many miles on it. while I had the pan off of it I looked up into the cylinders with the pistons all the way up and can still see the cross-hatching which lends itself towards my first impression that it's a very low milage motor.

 

My older LT1 came out at 108,000 miles. It had cross-hatch edvident all the way through the bore. The WORST bore had 0.0004" taper and out-of-round (that's four-TENTHS, not thousandths). The engine was never babied (as evidenced by the three sets of tires to that point), but never abused either (always warmed up and maintained). I didn't see a problem with that since it had Mobil 1 right after leaving the dealership.