Did you measure to be sure it hasn't already been bored? If it's that nice maybe it was redone previously. And then again alot of motorhomes don't get to be high mileage because they sit around most of the time. ===================================================================== Cheryl & Steve Mick wrote: > > My 413 engine doesn't appear to have any ring groove- I had considered > boring to 426, but would rather not at this time. Problem is finding 413 > pistons -so far the choice is having custom made forged pistons, or > Sealed Power still offers a cast piston, pin, ring kit. ( much less > expensive) I am planning about 9 1/2 :1 compression with 5500-6000 RPM. > Tops. Might do some occasional drag strip racing, but you know how it is > when you get the pedal to the metal urge . :) I would welcome anyones > opinion......................................MO.............. SW IOWA Rich Kinsley '64 Dodge Polara 4dr 318poly w/goodies ---- 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.