Hi
My friend bought brand new block and he told me new block all actual main bore sizes are different so he use some bore use standard size main bearing some under some oversize bearing to match clearance
Does this block normal? I mean all engine or all manufacture block come with like this?
Mitsibishi sell each individual bearing, so in this case he can buy each bearing standard size, under or over
But ACL or king doesn't sell individually
They are sell each full set STD or under or over sizes
Please give me some answer who have expert engine build

 

Sounds like it's needs to be line honed. The bores should all be very close. Within a few ten-thousandths.

 

If you look on the bottom of the block on the oil pan surface you will see etched into the metal the bearing sizes 1-4. Most people use clevite or acl bearings just check the bearing clearances you'll be fine. If ones off just use a mitsu bearing on that one.

 

thanks for answer me but does brand new block imperfection of main bore size is normal or factory defect ? that is what I want know

 

Pretty much normal for a lot of different engines.