On to balancing the pistons. Unfortunately I wasn’t able to balance the pistons and rods separately. I had to send them out for the rods to be removed from the original pistons and the the new pistons ‘hung’ on the rods. I didn’t want to mess with them and ruin a piston in the process.
I did weight all the pistons before they went to R&D to be hung on the original rods. This won’t be a professional balance by any means, but at least the pistons will be about the same weight and the piston/rod weight will be also about the same. I’ve sealed off the wrist pins as best I can to prevent any fine filings from lodging between the piston and its pin.
The recommended p rocedure is to remove metal from the pin bosses. With the pins in place I didn’t want to grind near them so I removed what I needed from the outside bottom surface and any adjoining casting ridges.
Once the piston difference was evened out I removed the remaining weight from the total piston/rod combination from the metal blob on the end rod cap. For example if the total weight was 1309 grams which was 7 grams heavier than the lightest piston/rod weight and the piston was 3 grams heavier than the lightest piston I first removed the 3 grams from the piston and then took the remaining 4 grams from the the rod cap.
After a couple of hours I had them all done. They all are now about 1302 grams each. My scale only goes to rounded grams. I could have done better with a scale that showed a couple of decimals. Even so this should help the engine run smoother.
Next: Getting the pistons in.