OK, I have a JDM ITR block (p72 casting) and the main caps it came with. I tried putting in a good GSR crank with ACLs, but it would bind up, so I took the block to get it align bored. Got it back, put the bearings back in and still no dice. Tried another known good crank, no dice. I am using ACL bearings and a USDM GSR crank, the proper sizes for the crank/block combo is all greens, and the mains plastigauge out perfectly, they just wont spin freely. I have tried a set of OEM greens and no go either with either crank. There is nothing under the bearings, everything is so clean and perfect and it just won't turn. I am at a loss here, someone please help!! I am wondering if JDM blocks use different sizing than USDM blocks.....

 

What order are you putting the main caps on? Did you lube it all up before you dropped the crank in and torqued the main caps on?

 

I am following the Helms to a 'T'. I have done this about 6 times before with zero problems, but this one is the only JDM block I have done. I was under the impression that they were all the same P72 casting. I even had this one align bored...*sigh*

 

Any ideas? I am going to check with a much more experienced engine builder tomorrow. Everything Plastigauges out fine, it just wont turn....

 

check roundness and measure mains, measure journals then do the math to see if the bearings your using are correct.
torque 1 main at a time to see if there is a specific one thats causing problems.

just 02