396 Machine work

There's a bit of work required to stick a 3/8" longer stroke into a stock engine case.  As you can see in the pictures below, the oil pan rail needed to be clearanced for the rod bolts.

Since the block wasn't bored-out at this point, I assembled a stock-bore piston onto one of the new rods.  This was used with the new crank to determine the amount of clearancing needed for each cylinder.  A die grinder was used to remove material, and I used a 1/16" drill bit to ensure that I had at least 0.060" of clearance everywhere (in most places, I tried to obtain even more room). What isn't shown here is the clearancing at the base of each cylinder.  Not much material needed to be removed there.

The Milodon caps were machined to fit the stock block registers, per the instructions (I did this step on a Bridgeport mill).  The holes for the side bolts were drilled and tapped by me, and I delivered the block to the machine shop with the caps installed.
Look at the top picture - you can see the dipstick hole.  Because of the size of the splayed caps, the stock dipstick tube will need to be trimmed-down about 1.5" shorter than stock.

Performance Engineering in Jenison, MI performed all the machine work, and did a wonderful job for a very reasonable amount of money.  The block was fitted with a torque plate (to simulate the loading of the installed heads), and bored and honed to 0.030" (4.030" bore).   The shop then line-bored and honed the main bore.  This step is recommended even when using the stock caps, as the stock main bore may not be dead-straight.

The rotating assembly (crank, rods, pistons, rings, and bearings) were balanced.  Due to the light weight of the Cola crank, not much is needed to bring the assembly into balance.  Two small slugs of Mallory metal were added to the front counterweight, and the stock flexplate counterweight was removed to bring the flexplate into neutral balance.

Performance Engineering measured the crank journals to select the proper bearing sizes, and did a final assembly clean on all the parts.  Total bill for machine work was around $750, plus the cost of the Mallory metal (approximately $30 in my case).