Displacement On Demand
Part I: Golen Engine Service Creates a Bigger and Better LT1(Continued)

Before the line hone the main caps are put back into place and the ARP studs are tightened down with a 3/16s Allen wrench, then the nut is torqued to 75 foot-pounds with ARP moly lube rubbed onto the threads. Copper center rings are used to seat the line bore in the main.

The main caps are bored 6 thousandths under final bore to allow for honing. Then a canther cutter is used to canther the edge of the caps to allow for better oil return.

The end caps must be bored manually, but first the sides must be ground perfectly at to ensure the bottoms are as well. A piece of an oil pump is used to keep the end cap perfectly straight for the line end to eliminate distortion.

Just like cylinder honing, line honing is done by feel. The line hone must be pushed back and forth manually allowing a margin for error. The clearances must be checked continually until it is just right. When Technician Dan Eddins is finished, the LT1 will have near perfect clearances to allow proper oil pressure and even wear on the cylinders.

The rod clearances must be increased to keep the rod nut from smacking against the block with the longer stroke. Dan uses a hand grinder with a carbide rotary file to make short work of this.

For this build Golen will be using optional SRP forged pistons, Eagle forged connecting rods, and an Eagle 4340 forged steel crankshaft into the bottom end of customer Val Becker's LT1. Comp Cams hydraulic roller lifters and a bumpier Comp Cams hydraulic roller cam was also used measuring .522/.543 inches of lift, 112 degrees LSA, and 232/244 duration at .050. Chad recommends staying modest with the cam size as practicality becomes a concern. That is the beauty of stroking the engine, as you can increase the horsepower without having to use larger cams and power adders, which will decrease drivability. It really is true that there is no replacement for displacement.

The 3.75-inch Eagle crank is noticeably larger than the stock
3.48-inch, nodular iron unit, providing the necessary stroke to increase displacement to 383 cubic inches. The cast steel construction also provides a raised fillet journal, as opposed to the rolled fillet journal of the stocker, which provides approximately 1/18 of an inch more support where the radius meets the fillet.

The Eagle crank is also internally balanced but will require additional balancing to the new rotating assembly. First, though, the counterweights must be cut because they are too wide to freely spin in the block. Cutting the block itself is another option, but not a good one, as it will decrease pan gasket clearance.

The crank is balanced with the rotating assembly by first weighing the connecting rods, pistons, wrist pins, rings and locks then constructing bob weights filled with metal shot to mock them. The four sets of bobweights are then placed onto the crank, alternating at 90 degrees.
It is then spun on a dual plane balancer, which measures where and how far out of balance the crank is.

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