okay so i went and i got wisco pistons and manley h beam rods with ACL/calico 7 bolt rod bearings for a 4G63/4G64 and i got my head ported and polished. now i need to put everything in and i staggered the rings and i put the rod bearing in and torqued the rod bearing caps to spec but now my engines teacher in tech school who btw is a american muscle guy is telling my that the rod bearings that came out of the car may be select fit to my crank. now im worried if i should use the acl ones. if anyone knows anything about this please help me out i dk if this muscle guy knows what hes really talking about or not. thanks

 

Have you had any machine work done to the crank or have it polished?

 

nope i didnt do anything to the crank i didnt even take it out of the car

 

the Factory rod bearings are select fit. If you look on the crank On one of the counter weights, You will see roman numerals stamped these indicating what bearings should be ordered. Acl makes standard fit bearings that should be just fine. The select fit difference is very minor around a tenth of a thousandth.

 

okay thank you very much that makes me alittle more comfortable now

 

You should still however check the clearances for all the bearings just to be sure everything is in spec. Yeah, it does take a decent amount of time to do it right, but you are investing a little time into a motor thats costing you a lot of money to build.

 

Yes, check the clearances with a bore gauge or at least plasigauge the clearances.