A good quality dial bore gauge is expensive and quite a bit different than a 2-point inside barrel mic. Plastigauge is a crude way to measure clearances and really is just to validate that you're in the ball park (it works in a pinch).
The dial bore gauges that are typically used are extremely accurate (if calibrated) and have 3 or 4 touch points (not like a 2-point barrel inside mic). They cost around $1300 - for a regular length one (sometimes you can find a used one for much less - but it may need calibration). If you have one with an extended length shaft (to reach into the various main bearings of a block), the price goes up. I simply cannot use a 2-point inside mic and accurately measure bearing clearances, taper, out of round, etc. (anywhere close to what a dial bore gauge can do) - also it is easy to scratch the bearing shells with all the fussing around.
Here is a picture of a Starrett dial bore gauge . . . not sure the size/range of it:
Starrett-2018-12-04_19-57-25.jpg
12-04-2018, 08:09 PM
Re: Bearing clearance
Hybrid Mode
