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Sign up for our E-newsletterPROJECT LS2, PART 3
Assembly of the short block
and cylinder head installation
by Mike Mavrigian
All photos by author
INSTALLING THE RELUCTOR WHEEL
The reluctor wheel features a series of teeth that provide crankshaft position signals via a sensor to the ECM. The wheel press fits to the rear of the crank, immediately forward of the No. 5 main bearing. The wheel features about a 0.007″ interference fit. While an OE LS crank is already fitted with this timing wheel, an aftermarket crank may or may not be provided with an installed wheel. If you need to install the wheel yourself, be advised that the clock position is critical for proper timing reference.
Since LS cranks feature no keyway or other index point (thanks a lot, GM), how do you know where to locate the wheel? As usual, Goodson rode to the rescue. The company offers a very handy (and damn-near essential) indexing and installation tool for LS reluctor wheel mounting. The RRJ-350 Reluctor Ring Jig (for Chevy 350 type applications) is a short steel tube that’s equipped with two indexing pins. An external tang secures a threaded stud, with the stud tip turned down to 8mm diameter. This pin engages into the sole 8mm hole in the reluctor wheel.
An internal guide pin (a threaded stud with the tip turned down to 11mm) engages into the 11mm blind dowel hole in the crank’s flywheel flange. This jig orients the reluctor wheel precisely in the correct timing position. The two dowel studs feature jam nuts to allow depth adjustment (you simply want to make sure that the 8mm dowel passes through the wheel’s 8mm hole and that the 11mm dowel projects out far enough to engage into the crank flange dowel hole).
Before attempting the installation, I lightly chamfered the entry hole of the reluctor wheel and lightly chamfered the edge of the crank’s reluctor wheel flange. Goodson’s instructions advise this chamfering to ease installation. The instructions also state that the wheel may be pressed onto the crank or heated to 450 degrees F for a slip-on fit. I admit that I did try to cold-press the wheel onto the crank but maintaining a square alignment of the wheel to the crank was difficult (hey, I’m a klutz). Ultimately, I took the easy way out and heated the reluctor wheel’s I.D. lip with a torch, slipped the wheel onto the Goodson jig and the wheel slid onto the crank as easily as a rock drops into water. My advice: install the ring by pre-heating it instead of potentially ruining the ring by cold pressing.
Caution: The ring is made of two plates riveted together. If you cock it out of alignment and continue to press, the plates can begin to separate. If this happens, you can pinch the plates together with C-clamps and carefully tack-weld it back together at the rivet hole locations. Just be careful to avoid creating a warp/runout condition.
Again, because the jig indexes to both the wheel and to the crank, misalignment isn’t an issue. If you expect to build LS engines, I highly recommend buying this jig. It takes all of the guesswork and time consuming measuring out of the equation. Don’t even try to press it on cold. Simply heat the ring, seat it onto the jig and place the jig and wheel onto the crank. With heat and the right tool, it’s easy.
INSTALLING THE CRANKSHAFT
After a final wash (hot tank followed by a soap/water rinse and blow-dry), the upper main bearings were installed in the block saddles. The Clevite thrust bearing (at No. 3 main cap) feature two thrust face oil grooves on one side and three grooves on the opposite side. The three-groove side must face the rear of the block. The lower bearing shells were installed to the main caps (again, with the three-groove side of the thrust bearing facing rearward) and all exposed bearing surfaces were liberally coated with Royal Purple Max Tuff assembly lube.
The caps must be installed in proper orientation. Each cap is number-stamped for location, as is the adjacent pan rail surfaces of the block. The side of the cap that features the number stamp must be placed adjacent to the number stamp on the block (place cap numbers closest to block numbers). This will orient the small curved tangs on the caps facing rearward, except for No. 5 cap where the tangs face forward (the number stamps for No. 1, 2, 3 and 4 are located on the left side of the block, while No. 5 is stamped on the left side).
With the crankshaft carefully laid onto the upper bearings, I then installed the ARP main studs (I applied a light coat of ARP moly on the block-side threads) finger-tight. The caps were then hand-installed, paying attention to cap angle, nestling the caps into position as evenly as possible. I then lightly snugged each stud using a hex wrench to about 3 to 5 lbs./ft. preload (basically just making sure that they were fully seated).
The aluminum block is very “alive” so any forces applied (such as main cap fastener tightening) will cause the block to move around. Keep this in mind when tightening the mains. Don’t be tempted to try rolling the crank after partial tightening. The main bores won’t straighten out until all primary main cap fasteners are fully torqued. Instead of following the OE torque/angle spec, our ARP main studs require a straight torque value. Following the proper sequence, I tightened the stud nuts (with ARP moly on threads and nut undersides) to 50 lbs./ft. at the inboard stud locations (closest to the crank) and 60 lbs./ft. at the outboard studs.
I started by carefully drawing the caps down by tightening the nuts to about 10 lbs./ft. I then continued by tightening the inboard stud nuts to 25 lbs./ft., followed by tightening the outboard stud nut to 25 lbs./ft. This allowed the caps to settle and provided an even baseline of clamping. I then tightened the inboards to their final value of 50 lbs./ft., followed by final-tightening the outboards to 60 lbs./ft. At this point, the crank rolls like butter. I checked crank thrust at 0.005″.
Once the primary stud nuts were fully tightened, I then installed the 10 (five per side) 8mm side bolts (threads and head undersides coated with ARP moly), tightening to 20 lbs./ft. These are tightened in sequence, starting at No. 3 main cap, followed by No. 4, No. 2, No. 5 and No. 1 cap locations.
CAMSHAFT
Since our cam is a steel roller (Crane’s P/N 144HR00162, grind No. HR-256/367-2S-14), I coated the journals and lobes with Royal Purple Max Tuff assembly lube and slid the stick into its bore. No surprises here.
Note: I tried to install an OE crank snout key but it was way too tall for the Lunati crank snout’s key groove. The 1.5″ radiused Lunati key (P/N CS001) fits perfectly, however. This is simply a tidbit I wanted to pass along. Don’t assume that the OE key will fit all aftermarket cranks, so make sure that you obtain a key from the crank maker (actually, Lunati supplied a key but I have to admit that I forgot about it until I attempted to install the GM key. Hey, I never said I was smart).
We chose a Performance Billet Gear Set (P/N 5623T), sourced from GM performance distributor Scoggin Dickey. This kit includes a double roller chain, cam gear, adjustable crank gear (with timing adjustment from 0 – +/- 4 degrees), a Torrington-type bearing that is placed between the cam retainer plate and cam gear, two spacer shims to move the oil pump out for the timing system clearance, and a drive gear for the stock type oil pump. The crank gear featured about a 0.001″ interference fit to the crank snout. I easily tapped it into place using a thick-wall aluminum tube to prevent marring the gear.
In order to obtain zero timing, simply position the reference dot on the cam gear at 6 o’clock and position the small “0″ mark on the outer circumference of the crank gear at 12-o’clock (the two dots should align). This places the cam’s dowel pin at just after 3 o’clock, and the crank key at about 2 o’clock.
Once the ARP cam nose-to-cam sprocket bolts were treated to a small dab of thread locking compound, they were tightened to 20 lbs./ft.
Next, an OE timing chain damper was installed to the block face, between the cam gear and crank gear. These two 8mm bolts were snugged to 18 lbs./ft.
Note: The timing system must be installed before installing the oil pump.
OIL PUMP
Our pump is a high volume/high pressure crank-driven unit from Melling (P/N 10296).
Before installing the oil pump, insert the external-toothed drive gear into the oil pump’s central drive gear. This external toothed gear (supplied with the timing set) serves as an adapter that is key-driven by the crankshaft snout. The external teeth on the adapter slides into the female-toothed gear in the oil pump. Apply oil to the teeth and carefully slide the adapter into the oil pump, engaging the male-to-female teeth (it’s a close fit but will easily install by hand).
In order to provide clearance for the thicker-than-stock timing chain setup, I installed the supplied spacer plates between the oil pump and the block face. I applied a bead of RTV to each side of these plates in order to provide a seal. All four oil pump mounting bolts were tightened to 18 lbs./ft., with a drop of thread locker applied to each bolt’s threads.
Note: The OE oil pump installation procedure calls for centering the pump to the crank snout. Mount the oil pump to the block, tightening the four mounting bolts to a mere 45 lbs./in. Then center the pump by nudging it around until you achieve an even 0.002″ clearance around the entire drive gear (stick a 0.002″ feeler gauge at one side and another 0.002″ feeler gauge 180 degrees from the first gauge). Once it’s centered, tighten the four mounting bolts to their final 18 lbs./ft. value.
RINGS
We opted for file-fit rings for out 4.005″ bores. Our rings (which were included with our JE pistons) include JE Pro Seal top rings S14000-5-1.5DMR ductile plasma moly. I filed these to achieve an end-gap of 0.018″. Our second rings, JE Pro Seal J24000-3-1.5IPC iron rings were file fitted with a gap of 0.020″. For a high performance street/strip application, JE recommends a top ring gap of Bore x 0.0045″; and a second ring gap of Bore x 0.0050″. Minimum gap for oil rings is 0.015″, which were good to go.
I file-fitted each ring to its assigned bore to accommodate any variance in bore diameter. A diameter variance from one cylinder to the next changes the end gap of the rings in that cylinder by a factor of pi (3.1416). For example, a cylinder that is 0.001″ larger in diameter will increase the ring end gap by 0.001 x 3.1416, or 0.003″. It’s critical to always fit each ring for the specific cylinder into which the ring will be installed.
I filed all of our top and second rings using Summit Racing’s rotary ring filer. It may not be as cool as an electric filer, but the diamond wheel cuts fast and clean, and it’s a bunch cheaper.
When checking ring radial back clearance for top and second rings, with the ring set in its groove and side clearance (ring face radius protruding out) at 0.001-0.002″, radial back clearance should be at least 0.005″.
Since our JE pistons feature a pin bore that intersects the oil ring groove, an oil ring support rail is necessary to complete the floor surface area for the oil ring package. The support rail installs at the bottom of the oil ring groove with the rail’s anti-rotational locking detent facing downward. When installing the support rail, rotate the rail until the detent falls into the void at the wrist pin hole.
Note: Do not install the support rail until the pistons are assembled to the rods since the rails will block the pathway for the wrist pins.
PISTON/ROD ASSEMBLY
Our full-floating wrist pins are secured with the supplied wire locks. Install the end of one lock at 90 degrees from the pin lock groove. Use a stiff small blade screwdriver, inserting the tip into the pin lock groove while you wedge the lock into the groove. As you walk the lock clockwise, you can insert a small screwdriver into the lower right access groove (two of these grooves are featured along the lower circumference of the pin bore). Using the screwdriver as a lever, pivot the screwdriver inboard to engage part of the wire lock into its groove. Then insert the screwdriver into the lower left access groove and finish levering the wire lock into place.
An option is to use Lockintool’s W-927 wire lock installer. This tool features a step-faced head that allows you walk the wire lock into place by working the tool in an angle and “rolling” the wire in a clockwise path into its groove. I will admit that it took me a while to get the hang of the technique but it does work well with a bit of practice.
After installing one wire lock, place the wrist pin against the lock and, using a brass drift, hit the lock to ensure full seating. Lube the wrist pin and assemble the connecting rod to the piston. Install the second wrist pin wire lock. JE recommends hitting both sides of the pin with a brass drift to ensure proper wire lock seating. Perform these lock-seating steps on a soft pad to avoid piston damage.
Once the rods are assembled to the pistons, install the oil ring support rail, making sure to place the rail’s small male dimple facing down and positioned over the pin bore void.
The oil ring package is then installed (expander ring, followed by the lower oil ring rail followed by the upper oil ring rail), followed by the second and top rings.
The JE second rings feature JE type laser-etched on the top of the ring and the top rings feature a small dimple at the top. Just remember that the inside bevel on the second ring must face down and the top ring’s bevel must face up.
JE’s recommendation for gap location is as follows: When viewing the bore from overhead, with the front of the bore at 12 o’clock, the bottom oil ring package rail gap is at 11 o’clock. The top oil ring rail gap is at 7 o’clock. The second ring gap is at 9 o’clock facing engine left and the top ring gap is at 3 o’clock facing engine right.
Tags: ARP, CAMSHAFT, CAMSHAFT SPECIFICATIONS, CRANKSHAFT, ENGINE ASSEMBLY, GOODSON, J&E, LS, LS2, LUNATI, MELLING, OIL PUMP, PISTON RINGS, RELUCTOR RING, ROYAL PURPLE MAX TUFF, WRIST PINS
