Pre-Installing Piston and Rod Assemblies - Checking Rod Bearing Clearance
With our crankshaft installed and the main bearing clearance confirmed, we moved on to verify that our rod bearing clearance was within specification.

We wiped down the number one rod and piston assembly.		Next, we cleaned the corresponding rod cap and fit one of our .010" oversized Clevite 77 rod bearings into place. Rod bearings are not location specific.
We proceeded to set the other rod bearing onto the rod. Like the main bearings, it's not necessary to use oil or assembly lube on the underside of the bearing. Although a small amount of oil can aid in installation.		Now we applied assembly lube to the "rod side" rod bearing but not to the "rod cap side" rod bearing since we'd be using Plastigauge in step 9 below.
Next, we wiped down the cylinders with brake cleaner and then coated them with 30 wt oil.		Some 30 wt oil was wiped onto the piston and skirts as well. Take note that pre-assembly doesn't require piston ring installation.
With rod bolt protectors in place, we dropped the number one piston into the number one cylinder.		ARP moly was applied to the threads of the rod bolts.
A strip of Plastigauge was set perpendicular across the rod journal.		The number one rod cap was torqued to 50 ft lbs.
Once the rod cap was removed, we confirmed that our rod bearing to crankshaft clearance was .001". The allowable range for the Ford 400 is .0008" to .0026".

Checking Piston-to-Head Clearance
Now that the rudimentary main bearing and rod bearing clearances were in the bag, the more exciting work was ready to be performed. Checking our 400's piston-to-head clearance would serve to validate that we correctly communicated our combo to all the parties involved. In this case those "party" members were the machine shop and the guys at Probe Industries.

Once the rod journal was wiped clean, we applied assembly lube to the "cap side" rod bearing surface.		No need to torque to specification this time since we were focused on the piston-to-head clearance. Snugging up the cap was suitable.
We rotated the crank by hand easily at the crankshaft snout just to make sure everything was spinning freely, it was.		We zero'd out a dial indicator on the deck using a Deck Bridge Tool from Proform.
Next, we positioned the deck bridge tool on the rear side of the piston just over the pin bore...		... and rotated the crank and took note of how close the dial came to zero. In our case, the dial came within .010" of zero. This was our deck height.
The same procedure was performed at the front side of the number one piston.		In that location, we also found the indicator came to .010" of zero. This was a good sign.
The piston and rod assembly was removed from the number one cylinder.		The same piston and rod assembly was used to confirm the deck height for each cylinder. Yes, we went through all eight.
All eight cylinders resulted in a .010" deck height. This confirmed that our block was square and that the correct amount of material had been "decked" at the machine shop.

(Cam Degreeing and Checking Piston-to-Valve Clearance)