No torque plate?

Since the hole is boring with torque plate on. Why it isnt being use in this video for measurement?

Good question!

Possibly because it was illustrating the method rather than an actual engine build?

TBH, it's been a while but I don't recall using a 'plate when checking - I may have used one, when available, but don't recall doing so.

Some engines are more susceptible to bore distortion than others, with most "open deck" engines having none.

Good question. I like to measure with and without torque plates to see what happens. Like Gord said, on some engines it won't make any significant difference.

In terms of the video, it's probably easier to give you a good view of the measuring process without the plate in the way.

From my experience it mostly depends on the type of cylinder head bolts torque and the height of the short block. The bigger the number is for any of two the greater the difference in bore size with/wo torque plate. If you are putting together a stock engine with stock components that's not going to see a lot of abuse chances are that you dont need a torque plate but as soon as you go up in the power department you beter off to use one...