im putting my ls block together, and i need to order new rod bearings. im getting acl bearings, but how do i tell what size bearings i need? i was told to mic it, but i dont understand how that would tell me what size i would need. do i plastigauge the old bearing to see if i need to order +.10, stardard, or -.10. or do i just order standard bearings? its a ls block with 105k miles on it. please help, i searched, but only got more confused.

 

I hope this helps

Main Bearing thickness by color
Blue 2.013-2.010 mm 0.0793”- 0.0791”
Black 2.010-2.007 mm 0.0791”- 0.0790”
Brown 2.007-2.004 mm 0.0790”- 0.0789”
Green 2.004-2.001 mm 0.0789”- 0.0788”
Yellow 2.001-1.998 mm 0.0788”- 0.0787”
Pink 1.998-1.995 mm 0.0787”- 0.0785”
Red 1.995-1.992 mm 0.0785”- 0.0783”


Rod bearing thickness by color
Blue 1.510-1.507 mm 0.0594”- 0.0593”
Black 1.507-1.504 mm 0.0593”- 0.0592”
Brown 1.504-1.501 mm 0.0592”- 0.0591”
Green 1.501-1.498 mm 0.0591”- 0.0590”
Yellow 1.498-1.495 mm 0.0590”- 0.0589”
Pink 1.495-1.492 mm 0.0589”- 0.0587”
Red 1.492-1.489 mm 0.0587”- 0.0586”

 

This is the tool you would use to "mic" it.

I would follow boosted hybrids instructions on his forum

http://www.boosted-hybrid.com/viewtopic.php?t=326

basically plastigauge your old bearings to make sure there is enough clearance. If clearance checks out go ahead and order the same size bearings.