by Mike Mavrigian
FILE FITTING THE RINGS
Because of our over-honed cylinder diameters (4.263″), standard size rings wouldn’t work, so I started with a set of Total Seal rings P/N CR7190 35, supplied with our Diamond pistons. These are intended for a bore diameter of 4.268″ (1/16″ top, 1/16″ 2nd, 3/16″ oil), requiring a custom file-fit.
In terms of top and second ring end gaps, Total Seal’s recommendations for a naturally aspirated engine is to achieve 0.0045″ of gap per inch of bore diameter for the top ring and 0.0035″ of gap per inch of bore for the second ring. 4.263″ x 0.0045″ = 0.01918″. I simply rounded off and file fit the top rings to achieve a gap of 0.020″. For the 2nd rings, 4.263″ x 0.0035″ = 0.01492″. I filed our second rings for a gap of 0.015″.
Using Summit’s adjustable ring seating tool, insert the ring into the bore and square the ring. The entire ring circumference must be equidistant from the top of the bore in order to obtain an accurate gap measurement.
Measure ring gap with a feeler gauge. I file-fit all top rings at 0.020″, all second rings at 0.015″ and all oil rails at 0.016-0.017″.
I filed all rings on my Summit diamond-wheel ring filer. The crank handle must be rotated to move the wheel downwards at the front. This forces the ring flat onto the tool base. Your left hand is required to push the ring into the wheel during grinding (but I was shooting the photo with my left hand, so sorry about the photo).
After confirming proper end gap in the cylinder bore, carefully de-burr the freshly-filed edges to remove any burrs. A fine flat file works well.
After deburring, carefully examine the edges to confirm smoothness. Be sure to clean all rings before assembly using a fast-evaporating solvent (alcohol or brake clean solvent) and a lint-free towel.
Once all pistons, rods, pins, caps, bearings, rod bolts and rings were thoroughly cleaned, everything is arranged in order (per bore location) and ready for assembly.
Never assume that oil ring rails provide adequate clearance out of the box. I checked ours, and I found zero gap. Oil ring rails require a minimum of 0.015″ clearance (you can get away with as much as 0.025″ or so). While it was tedious work (their hard little buggers), I file fit all 16 oil ring rails to achieve a gap of 0.016″ – 0.017″.
OUR BORE DIAMETER RING LOCATION END GAP
4.263…………………………….OIL RAILS………………0.016″ – 0.017″
When checking ring end gap, place the ring in its intended bore (I always fit each ring pack to an assigned cylinder for tailor fitting), place the ring squarely inside the bore about ¾” – 1″ below deck. The ring must be square (equidistant from the deck all the way around). To speed this up, I use Summit’s adjustable ring squaring tool. Simply size the tool for your bore, place the ring in the bore (close to the top of the cylinder), insert the squaring tool and push down until the tool outer body rests on the block deck. This type of tool saves a lot of time.
I used our Summit Racing bench-mounted ring filer, which is a very affordable and easy-to-use ring filer. Position the ring onto the tool’s base, with an end butted against the diamond wheel. While applying light pressure of the ring end to the wheel, manually rotate the filer’s crank to remove material. Note: only rotate the diamond wheel so that the wheel rotates downward in relation to the ring. This diamond abrasive wheel is very aggressive, so file in small progressive steps, re-checking ring gap in the cylinder bore as you go. Make sure that you thoroughly clean the ring before test-fitting in the bore!
It’s always a good idea to verify ring fit to the piston’s ring grooves. Ring to piston groove back clearance (where the inner diameter of the ring faces the base of the ring groove) should be a minimum of 0.005″. Ring to groove side clearance (with the ring seated on the bottom of the land, and measuring clearance between the top of the ring and the roof of the land) should be a minimum of 0.0015″ to a maximum of 0.003″.
Once all rings were file fitted, the pistons, pins, rings, rods, rod caps, rod bolts and rod bearings were meticulously cleaned and organized on our Lista workbench.
Rods were then assembled onto pistons. The Diamond pistons feature full-floating rod pins, which must be secured with pin locks to prevent them from walking out of the piston pin bores. Diamond supplied round-wire lock clips, one lock per side of each pin. One wire lock is first installed into the piston pin bore lock groove. These can be tricky if you’ve never installed them before, but once you get the hang of it, it’s really no big deal. Instead of fighting and prying the lock into position, I used a handy wire lock installation tool from Precision Engine Service (Waxhaw, NC). First, I temporarily installed the piston pin into the piston bore. I then installed a small wire clip (supplied with the wire lock tool). This keeps the pin from sliding out. On the opposite side of the piston, I then inserted one end of a lock into its groove (with the lock’s gap positioned near the 6 o’clock position (so that the end of the wire lock is adjacent to the pin bore’s access grove for future service). Applying finger pressure to keep the wire lock up against the bore entrance, I used a small flat-blade screwdriver under the exposed end of the lock, gently prying it into the bore entrance. Then, using the wire lock installer tool (this features a stepped contact face), simply walk the tool along the wire lock in a rotary motion, and the lock pops right into its groove in the pin bore. I then remove the wire clip from the opposite side, remove the pin, lube the pin with Max Tuff lube, insert eh pin into one half of the pin bore, insert and align the rod small end in the piston and continue to fully insert the pin. The remaining wire lock is then installed. Once you become accustomed to the steps, you can assemble each remaining rod/piston in a matter of minutes.
The Diamond pistons were supplied with wire-type pin locks (one required for each end of the pin). Remember…for full-floating pins, a locking device (wire or spiral) is needed to retain the pin in the piston.
I installed the wire lock tool’s spring clip in one side of the piston pin bore. This engages into the pin bore’s locking groove, allowing you to temporarily install the rod pin without the pin sliding out. This makes it easier to install the opposite-side pin wire lock.
Precision Engine Service offers a handy wire lock installer tool (different sizes are available for various pin bore diameters).
Once the wire lock has been started at one end of the groove, the installer tool is walked around the perimeter of the lock to easily snap it into the groove. This tool is a real time saver.
Note the location of the wire lock’s gap. I placed it so that one end is reasonably close to the service access groove. This makes it easier to remove the lock during future service.
The oil ring expander ring ends must cleanly butt together and cannot be allowed to overlap. Pay close attention to this while installing the lower and upper oil ring rails.
Our rod bearings are Clevite CB743HN, sized for our 2.200″ rod pins.
Naturally, you need to be aware of rod-to-piston orientation. Each rod’s big end must be positioned so that its larger edge chamfer faces the corresponding crank fillet. Each piston, because of the valve reliefs, needs to be oriented to accommodate the cylinder head valve layout.
Once the rods have been assembled to the pistons, install the upper rod bearing into the rod big end saddle, and the lower rod bearing into the cap. Remember to position the rod bearings properly. Each rod bearing (on its backside) is stamped UPPER or LOWER. Don’t mix these up. Upper bearings must be installed to the rod and lower bearings must be installed to the rod caps.
Install the rings onto the pistons. First install the oil expander ring into the oil ring groove, making sure that the ends but flush against each other. Next, install a lower oil ring rail into the piston’s oil ring groove, capturing the lower edge of the expander ring. Then install the upper oil rail. Diamond recommends that the oil rail gaps are to be oriented with the lower rail gap at 7 o’clock and the upper rail gap at 11 o’clock (relative to the front of the piston).
The second ring is then installed (with the dot on the ring facing upwards), with its gap at 9 o-clock. The top compression ring is then installed (with its inner chamfer side facing upwards), with its gap at 3 o’clock (again, relative to the front of the piston as viewed from overhead).
Pay attention to rod bearing locations. Some engine applications, such as this Ford FE, feature dedicated upper and lower rod bearings. Upper rod bearings (if so marked) must be installed to the rod saddle, and lower bearings must be installed to the rod caps.
Connecting rods must be oriented to the crank’s rod journal with the rod big end’s largest side chamfer facing the journal fillet. In this photo, the rod’s large chamfer is seen at the right. The larger chamfer provides clearance at the crank rod journal fillet.
This closeup of a rod with upper bearing installed shows the large rod big end chamfer. Notice that the rod bearing is spaced slightly away from the fillet side. This insures that the rod bearing edge will not contact the radiused fillet.
Once the rod bearings have been final-installed to the rods and rod caps, lube the bearing faces. I favor Royal Purple’s Max Tuff assembly lube. It’s super-slick and it clings well, making it great for engine storage and for initial startup.
Once all rods, pistons, rings and bearings have been fully assembled, the components are laid out on our Lista workbench in an organized manner. Maintaining cleanliness and organization is key to a successful build. There’s no such thing as too-clean.
Using a clean plastic tub on the workbench to catch excess oil, each ring pack and piston skirts are drenched in clean 30W engine oil. Basically, you want to drown the ring pack, pin area and skirts. Don’t worry about excess oil on the piston domes. You can wipe the domes clean after the pistons have been installed in the block.
At this point, once all ring packages have been installed), I drowned the piston ring package and the piston skirts with clean 30W engine oil. Each cylinder bore was also thoroughly lubed with oil as well. The exposed faces of the upper and lower rod bearings were coated with Royal Purple Max Tuff assembly lube, and the rod bolts were coated with ARP moly (threads and under-heads).
In order to compress the ring package for piston installation into the block, I used one of Summit’s adjustable tapered ring compressors (these are offered in a variety of bore ranges). This tapered billet aluminum ring compressor provides bore diameter adjustment from 4.250″ to 4.340″ (our bore size is 4.263″). Install the ring compressor onto the piston by inserting the rod through the top of the compressor, eventually nestling the piston and rings into the compressor. With the appropriate crank rod journal positioned near bottom-dead center, the rid big end is carefully inserted into the bore, until the piston skirts enter the bore. While keeping the ring compressor flat against the block deck and the piston/rod oriented for alignment, you can fist-push the piston into the bore (or you can tap the piston into the bore using a clean plastic hammer handle against the piston dome, tapping the hammer head with your palm). Once the piston dome is flush with the block, remove the compressor tool and continue to push the piston until the upper rod bearing gently seats against the rod journal. Pay constant attention to rod big end location to prevent nicking the crank’s journal and to keep the side of the rod big end parallel to the counterweight and fillet area. Install the rod cap (make sure that the cap is oriented properly for cap-to-big-end orientation).
The piston ring compressor installs to the piston from the bottom (pass the rod through the compressor until the compressor captures the pistons). Shown here is an adjustable ring compressor from Summit, an aluminum compressor that features one split and an adjustable worm-drive clamp.
With the compressor capturing the entire ring package, tighten the compressor’s clamp to a slightly snug fit. The compressor inside diameter is tapered (bigger at the top and smaller at the bottom) to compress the rings as the piston is pushed down into the cylinder. After some practice, you’ll obtain a “feel” for the proper amount of clamp tightness.
With the rod inserted into the bore (oriented correctly), and with the crank’s rod pin moved near BDC, the piston skirts are inserted into the bore and the compresor tool base is held flush with the block deck. With the ring compressor adjusted properly, a firm push with your fist will move the piston through the tapered compressor and into the bore. Never try to beat the piston into the bore with a hard object. If the rings get hung up on the block deck, you’ll damage not only the rings but possibly the piston ring lands as well.
This particular Summit ring compressor will adjust for bore diameters ranging from 4.250″ to 4.340″, which worked out just peachy for our 4.263″ bores.
There are two methods available for rod bolt tightening…you can follow a torque value or you can tighten by monitoring rod bolt stretch. All threaded fasteners are designed to stretch by a specific amount in order to achieve proper clamping load. Using the stretch method allows for a more accurate and consistent bolt clamping load. While the stretch method is admittedly more time consuming, it’s worth the effort, especially for an engine that is expected to see hard loads and high rpm. First, using a rod bolt stretch gauge, insert a rod bolt onto the gauge’s anvils, providing a preload of about 0.050″ or so (just to make sure that you have some preload on the gauge). Zero the gauge face. Then install the rod bolt onto the rod and, using a torque wrench, tighten to about 40 ft-lbs. Without disturbing the stretch gauge’s indicator face, install the stretch gauge onto the rod bolt to determine how far the bolt has stretched. Remove the gauge, slightly hand tighten the bolt further, re-check with the stretch gauge, etc., until you have achieved the recommended amount of bolt stretch. In our specific case, our ARP 7/16″ x 1.4″ 8740 rod bolts are specified (by Scat) for a stretch amount of 0.0046″. If you choose to tighten these same rod bolts by the torque method instead, Scat recommends reaching a final torque value of 64 ft-lbs.
If you opt for tightening your rod bolts by monitoring bolt stretch, you’ll need a stretch gauge. Shown here is a billet aluminum stretch gauge from GearHead Tools, featuring a handly finger ring for easier handling. First, use the gauge to obtain the relaxed length of the rod bolt. Place a rod bolt on the gauge anvils, adjusting the bottom anvil to create a slight preload on the gauge, then zero the indicator. The bolt is then installed and tightened in stages, while stopping to place the gauige onto the bolt and monitor the amount of bolt stretch that has been induced at that point. When that particular bolt has been tightened to a specified stretch (the spec is provided by the bolt maker), the gauge is then re-zeroed for the next bolt.
Tightening rod bolts using the stretch-monitoring method is time consuming, but the results are worth the trouble. Using the stretch method eliminates the variables of friction (as encountered when using a torque wrench), providing more accurate rod bolt clamping.
After each pair of rods have been installed onto a common rod journal, use a feeler gauge to check for rod sideplay. Spread the big ends apart with your fingers and insert the feeler gauge between the rod big ends. I measured 0.024″ sideplay in this build. In general terms, you should have at least 0.015″ to 0.025″ sideplay. If too tight, the big end faces may need to be lightly refaced to provide adequate clearance. It’s best to mock-install rods during the pre-assembly/test-fit phase in case corrections are needed. Regardless, always check rod sideplay during final assembly.
OIL PUMP, PICKUP AND PAN
Before mounting our Melling high-volume oil pump P/N M-57HV, I installed an ARP hardened pump drive shaft P/N 154-7902 (this allows the distributor to drive the pump). One end of the shaft features a small stopper plate. This stopper end of the shaft is inserted into the block, positioning the upper tip into the shaft’s guide hole. With the shaft in place, a thin mounting gasket is placed on the block and the pump is installed, while carefully aligning and engaging the lower shaft hex tip into the pump’s drive hole. The pump was mounted to the block using two 3/8″ x 16 x 1.25″ grade 8 bolts (with loc washers and thread locker compound applied to the threads). I torqued these bolts to a value of 25 ft-lbs.
The pickup (in this case, a Milodon pickup, P/N 18370) was then mounted to the pump using a pickup-supplied gasket and a pair of 5/16″ x 18 bolts, also grade 8, and also equipped with loc washers and thread locker.. These bolts were tightened to 18 ft-lbs.
Before installing the oil pump, remember to first install the oil pump drive shaft. The shaft features a stopper clip near the top. Insert this end into the block for future distributor engagement. Be sure to lube the shaft.
A thin gasket is positioned between the block and the oil pump.
The Melling high-volume oi pump is installed, along with a Milodon pickup. The pair of 3/8″x16 bolts that secure the oil pump to the block were treated with thread locking compound, in addition to the use of loc washers. The pickup was attached using a pair of 5/16″ x 18 socket head cap screws (hex heads work work just fine, but I had a bunch of grade 8 SHCS lying around, so what the heck). Be sure to use grade 8 fasteners for both pump and pickup mounting. By the way, I tend to remove an oil pump’s cover and pack the gears with lube (I use Max Tuff) and reinstall the cover, before installing the pump. This assures that the pump gears won’t run dry during initial engine starting.
Once the pickup is installed, carefully measure the distance from the block’s oil pan rail to the pan-side of the pickup screen. The pickup screen should be approximately 5/16″ or so from the floor of the oil pan sump. Measure the depth of the pan sump to compare. This Milodon pickup features a welded-on bridge below the screen, serving as an insurance spacer.
Our oil pan of choice for this build is a Milodon 7-qt steel pan, P/N 31130. ARP stainless steel bolt kit, P/N 455-1802. These 5/16″x18 x 1″ bolts feature oversized flange heads with 3/8″ male hex heads. Each bolt’s threads were coated with threadlocker, and all bolts were tightened to 15 ft-lbs., in an alternating pattern to distribute the clamping load. A Victor cork/rubber gasket was RTV-adhered to the block side, making the pan serviceable in the future.
Note: Since an OE dipstick tube would interfere with one of the engine’s exhaust header tubes, I opted for a stainless braided flexible dipstick tube kit. Milodon offers a flexible dipstick kit P/N 22034, but this was on back-order for so long, I gave up and bought a Lokar kit, their P/N ED-5012. However, the supplied flexible dipstick was too short (would not touch oil). Their stick (from where it mates to the handle head to the bottom tip) measured 17″, which was about 1.5″ too short. I contacted Lokar and purchased a universal-length stick (just the cable, without handle), and trimmed it to an exposed length (from the bottom of the handle to tip) of 19″, which worked out for this particular application.
OUR PRODUCT SOURCES
1863 Eastman Ave.
Ventura, CA 93003
COMP CAMS (camshaft & lifters and ZDDP additive)
3406 Democrat Rd.
Memphis, TN 38118
DIAMOND RACING PRODUCTS (custom pistons and rings)
23003 Diamond Dr.
Clinton Twp., MI 48035
GOODSON TOOLS & SUPPLIES (engine stand and shop supplies)
156 Galewski Dr.
Winona, MN 55987
GRESSMAN POWERSPORTS (machining)
904 Lime St.
Fremont, OH 43420
JOE GIBBS DRIVEN (dedicated break-in engine oil)
13415 Reese Blvd. W.
Huntersville, NC 28078
LEVEL PERFORMANCE (dyno session)
2251 Napoleon Rd.
Fremont, OH 43420
MAHLE-CLEVITE, INC. (bearings and gaskets)
1350 Eisenhower Place
Ann Arbor, MI 48108-3282
MELLING SELECT PERFORMANCE (oil pump and pickup)
P.O. Box 1188
Jackson, MI 49204
MILODON (oil pan)
2250 Agate Court
Simi Valley, CA 93065
PRW INDUSTRIES, INC. (shaft-mount rocker system)
193 West Orangethorpe Ave.
Placentia, CA 92870
ROYAL PURPLE (Max Tuff assembly lube)
1 Royal Purple Lane
Porter, TX 77365
SCAT ENTERPRISES, INC. (crankshaft and rods)
1400 Kingsdale Ave.
Redondo Beach, CA 90278-3983
SUMMIT RACING (shop tools)
P.O. Box 909
Akron, OH 44309-0909
TREND PERFORMANCE PRODUCTS (custom pushrods)
Warren, MI 48089