kommon_sense said:The difference between .050" and 0.5mm may be significant because 0.050" is 1.27mm. The d-series cylinder walls are thin already. According to my numbers you would have to have a 78.11mm bore in order to be a 1.725L. You don't want to bore a d-series past 77mm... So you need to double-check those numbers to make sure that you didn't just build a motor that you can't boost...