Improves traction and reduces wheel hop.
The JDM K20A type-R engine block would be removed from production assembly line by an experienced Honda engine technician to torque the connecting rod bolts to factory specification by hand using micrometer to measure connecting rod bolt stretching.
The VTEC system on engines like the K20A3 only operate on the intake cam; at low rpm only one intake valve is fully opened, the other opening just slightly to create a swirl effect in the combustion chamber for improved fuel atomization.