Subscribe to Precision Engine
Sign up for our E-newsletter
All main studs are installed finger-tight, with just an added scooch to make sure they’re seated.
The main caps slid on easily, with no stud splaying interference.
Be careful when installing the main caps. Each cap is numbered for location, as is the block. Be sure to install caps with cap numbers on the same side of the block as the stamped-in block numbers.
The 8mm side bolts are installed after torquing the main stud nuts. Per ARP’s instructions, we tightened the inboard stud nuts to 50 lbs./ft. and the outboard nuts to 60 lbs./ft. The side bolts are tightened to 20 lbs./ft.
When using ARP’s side bolts, you’ll need a 10mm 12-point socket.
The side bolts are slightly recessed. Be sure to apply ARP moly to bolt threads and head undersides.
The tightening pattern for the main caps is shown here. Start at the No. 3 cap. Tighten the inboard nuts first, followed next by the outboard nuts, then by the side bolts.
Scott Gressman checks main bore diameter with all caps fully tightened. Our block main bores measured 2.750″.
Gressman begins to set up our block in his RMC V40 CNC machine for bore checking and deck-cutting.
With the block supported on the main bore bar and with the cam bore index bar in place, the CNC begins its block-measuring program.
Here the CNC probe contacts the pan rail as the machine begins to create a dimensional “map” of our block.
The CNC machine’s probe obtains deck height measurements, recording each deck’s surface height (with regard to crank centerline), which provides information relative to deck height front-to-rear and side-to-side. This information lets the operator obtain data regarding deck height, squareness and twist.
Each cylinder bore is checked for location (relative to the crankshaft) and diameter.
Once the block has been measured, all data concerning bore location and diameter, as well as deck heights, is clearly viewable on the machine’s monitor. The operator can quickly see where the lowest deck height point is located, allowing him to determine if and how far the decks will be cut.
Gressman starts the deck-cutting program. Our decks were cut to a finished height of 9.234″ in order to obtain precise deck squareness and parallelism.
Once the decks were cut, the block moved to Gressman’s Rottler honing machine. BHJ deck plates were installed, with the ARP head stud nuts torqued to 80 lbs./ft. (threads lubed with moly).
Gressman honed our bores to 4.005″ using 500-grit diamond stones, followed by four strokes with silicon-carbide-plateau brushes.
Gressman verified all bores for diameter and taper.
Cylinder head fasteners are tightened in three equal steps. Our ARP stud nuts call for a final torque of 80 lbs./ft. with ARP moly. The 8mm stud nuts are to be tightened to 22 lbs./ft. with moly.
Our Lunati rod big ends averaged 468 grams, with small ends at 213.5 grams.
Our JE pistons weighed out at 401.5 grams.
Our rod pins weighed in at 106 grams.
A single piston ring pack weighed in at 35 grams. Each ring support rail weighed an additional 7.5 grams.
Our bobweights were set at 1799.5 grams.
Tags: ARP, BALANCING, BLOCK DECKS, BLOCK MACHINING, BOBWEIGHTS, CNC, CYLINDER HONING, GRESSMAN POWERSPORTS, LIFTER BORES, LS, LS2, MAIN BORE, MAIN CAP TORQUE, TORQUE PLATE
