.055 over for a 440 is now a common size since that is also a chevy size piston. I have used .055 in a 15 to 1 - 500 inch 440 motor with no issues. Earl They said 0.060 was OK all day long on all B / RB blocks. If I figure correctly about 0.062 + /- is the difference in the 413 & 440 bore. Should be no problem?? I have bored B / RB blocks out 0.063 and more for clearance with NO problems. Maybe I was just real lucky but the article seems to back me up. Just my II. Herb -------Original Message------- From: Gary H. Date: 2/2/2009 4:25:27 PM To: 1962to1965mopars@xxxxxxxxxx Subject: Re: RE Pistons? Good read, thanks. I don't see anything there that contradicts the argument not to exceed a 0.040" bore on a 413 to get to 440, though. Gary H. -----Original Message----- >From: Herb > >Just something to read!! > >http://www.440source.com/blockinfo.htm > >Herb > >-------Original Message------- > >From: Gary H. > >Date: 2/2/2009 3:33:15 PM > >To: 1962to1965mopars@xxxxxxxxxx > >Subject: Re: RE Pistons? > > > >Seems I read that boring to 0.020" is good, but not to exceed a 0.040" bore >413 to 440 would exceed that bore model, yup. > > > >Gary H. > > > >-----Original Message----- > > > > >I can't > >>bore a 413 to a 440 piston. I can go to 426, but cylinder walls would be > >>thinner than I would be comfortable with. ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html. [Non-text portions of this message have been removed] ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html. ---- Please address private mail -- mail of interest to only one person -- directly to that person. I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic. Thanks! '62 to '65 Mopar Clubhouse Discussion Guidelines: http://www.1962to1965mopar.ornocar.org/mletiq.html.