That may be true, but how many 340 blocks have I run across in the last 10 years? 2. I bought the second one, a '70 casting that looked like it had sat for many years in the Seattle weather. It cleaned up .020 and now makes those camaro guys think twice about staring me down. Any time you intend to build an engine, make sure you do the proper machining anyway. Making up the difference with the right size overbored pistons is everything. Protect your investment, and don't forget to tip your machinist. :toothy10: