Posted by John Moschinger on March 22, 1999 at 16:48:34:
I need some help from some of you who have re-built flatheads before.
I am about to put some rings in my 1953 230 CID Flathead and I need to know if the pistons in the unit are for sure standard bore. There are no marking on the top of the pistons. Does this mean that they were intended to go in a standard bore? What diameter would the original piston be, if the original bore diameter is 3 1/4."
I have a set of pistons that are clearly marked .060 on top, and I think that oversized pistons are always marked with the size. I also have a replacement standard sized piston that is clearly marked "STD" on top. I can measure the bore of the block at the ridge and it measures exactly 3 1/4" (as closely as I can measure with my vernier caliper). I cannot reliably measure the diameter of the pistons in the block, but will be able to shortly.
Any insight would be helpful. I will have the correct measuring tools later on in the week, but if I can resolve the size of the pistons I can order the rings in for work this weekend.
As a little back up, when I pulled the crank, I found what appeared to be the original factory bearing on both the mains and rods. Both were .001. Thats 1/1000th. Although .001 was available to the Dodge dealerships I believe that this engine was shipped with .001".
Thanks again
John Moschinger
Mesa, AZ - 83 degrees and Sunny
60 D-100 Panel(yes I'm putting a '52 engine into a 60)