6. TCI Automotive offers every kind of flexplate you could want for your Chevrolet powerplant. These showcase two different styles; on the left is the late-model SBC (smaller pattern), while on the right is the early model piece. More often, stroker small-blocks require a flexplate with the external weight on it to be balanced properly.
7. As rods and pistons get lighter, getting the correct balance becomes much more critical. Our Mahle flat-tops for example, weighed .0535 grams, which is fairly light, but you can order them even lighter.
11. Two of these fixtures support the crank’s journals and are what actually sense how balanced the crank is. There’s also a magnetic degree sensor that attaches to the snout. Then, by using these inputs, the computer reveals to the machinist at what degree the crankshaft is either too heavy or too light and by how much.
8. The counter weights of a V-8 crankshaft are positioned very specifically by GM to offset the weight of the rod; everything from the bottom of the big end to the top of the piston. It’s when we start to add heavier pistons, with lighter rods and the opposite in different configurations that the engine balancing becomes crucial.
12. If the crank only needs a little weight added, some light welding is done on the counterweight.
9. Once the total weight of the pistons assembly is calculated, it’s then matched using special fixtures that hold lead shot.
13. At times, it’s acceptable to drill out the factory counterweight if minimal material needs to be removed.
10. These fixtures attach to the crank journals and simulate the exact weight of your piston and rod combination.
14. The pistons also get shaved down to the lightest weight of the bunch. The proper area is just under the pin lock.
15. On aftermarket pistons with short skirts, it’s acceptable to spin them in a lathe, however, on stock type pistons with long skirts, you have to lighten them by hand.
16. The guys at West Coast Balance Shop in Santa Ana, California also work with high-powered engines, so they aim to balance everything as perfect as possible. By dialing the balance machine to the smallest tolerances and by carefully adding or removing metal, their work often comes out within a fraction of a gram from being totally zero balanced.