This tool squares the ring exactly 1/2-in down the bore all the way around. This ensures that an accurate gap measurement can be made.
Knowing the intended use of the car, how hot the rings could get, and using square root calculations off the cylinder diameter, Gerner determines the optimal ring gap that will seal without ring end butting.
Gerner checks his ring gaps with a feeler gauge.
After checking ring gaps our pistons are ready for assembly to the connecting rods. The final determined ring gaps by Gerner were 0.018-in for the top ring and 0.020-in for the second ring.
FRP only uses a rod vice when torquing and removing rod bolts so that accurate concentricity (roundness) measurements and bearing clearances can be made. A standard vice shouldn't be used.
FRP's concentricity checker is manufactured by Sunnen, and is a type of bore gauge, which measures the roundness of the rod. FRP checks all rods before installing them. Ours were well within .0001-in!