B18 Rod Bearing Clearance

One often overlooked part when building an engine is the bearings.

B18 rod bearing clearance.

Does anyone know why the crank main journal specs and oil clearances are different for the 3 journal. The clearance is measured 90 degrees to the bearing parting line which is the thickest part of the bearing bearing thickness tapers slightly toward the parting line. Then determine the oil bearing clearance specs by either buying the manual for your engine or im sure someone could give you a good range to work with. We do so many engine builds that we have many of these bearings in stock.

Just ran the math and a factory spec 1 89 big end bore on a b18 rod subtracting a pair of green bearings at 0590 each comes out to 1 771 yet when green bearings are in the rod and torqued to spec the big end is measuring 1 7732 022 larger than the math says. Plus i ll be installing forged rods does this make any difference. P p mb main bearing set p p cr con rod bearing set p p cs camshaft bearing. Compression height of the pistons was 30 1 mm and all this ensured 1 83 liters of displacement.

Final torque 1 and 4 rod caps if clearance if ok. Rotate more if necessary so that the 2 and 3 rod caps will be accessible. Inside this unit an 89 mm stroke crankshaft and 137 mm long rods were installed. Br br these are a std size bearing and are king s race series bearing br p description.

Rotate crank until 1 is at top dead center tdc. Jump to latest follow 1 2 of 2 posts. All of the b series engines as well as k series engines share the same main bearing design. Only my b16b ones.

B18 cylinder block is made of aluminum its deck height is 211 84 mm and bore diameter is 81 mm. Hopefully the factory set the clearances up tight so now that the std bearings i put in give between 6 ten thousands and 1 thou more clearance than the factory built in i will still be in a good range for performance bearing clearances. Remove rod caps and double check clearance with plastigage. Final torque 2 and 3 rod caps if clearance is ok.

All b series and k series crankshaft main bearings have an upper and a lower bearing. Reducing the oil clearance between the rod and main bearings and the crankshaft has a number of advantages. 2 1643 2 1653 the oil clearances are the same for b18b and b18c. I have been reading that 0 0025 seems to be pretty standard for a performance sbc on both rods and mains.

Remove rod caps and double check clearance with plastigage. I won t have the conrods that was on the b18 crankshaft. Honda a18 a20 b20 b18a b18 b16 b17 p p bearing types. 1 2 4 5.

Getting a quality set of bearings can directly determine the longevity of your engine. Crankshaft main journal bearing clearance connecting rod bearing clearance piston ring gap clearances if someone s got them aswell any other info on building a b18c 6. 2 1642 2 1651 3 b18c. 2 1644 2 1654 3 b18b.

Joined jun 29. The journal specs are.