The Buick 400 was dyno'd after it was built, so we know the cam and ignition timing are right. If your engine was not run on a dyno, you will want to line up the mark on the balancer with the timing tab on the engine block. We usually line up the mark with the initial timing setting-in this case, 15 degrees BTDC. To make sure the engine is on the compression stroke, pull off a valve cover and make sure both No. 1 rocker arms are loose or peek into the spark plug hole and look for the top of the piston. On most domestic non-Cadillac V-8 engines, the cylinder that is the farthest forward on the block is No. 1.