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Sign up for our E-newsletterWE BALANCE AND BEGIN ASSEMBLY
text, photos and assembly by Mike Mavrigian
Crankshaft balancing was next on the agenda. Since the Diamond pistons are already weight-matched by Diamond, and the Scat connecting rods are weight-matched at both small and big ends, we didn’t need to perform any weight corrections to those components (I double-checked all piston, rod small end and rod big end weights on a digital scale just to verify).
Our Scat connecting rods were extremely consistent in terms of weight matching. All small ends weighed in at 245.5 grams, while all big ends weighed 578 grams. No weight corrections were needed. Here the small end of a rod is weighed on a digital scale.
The crankshaft was internally balanced at G&G Balancing in Strongsville, Ohio.
After weighing a piston, piston pin, one rod bearing set, a rod small end, a rod big end, one set of rings and our pin locks, Gary at G&G assembled our bobweights and installed them (each bobweight carefully centered on the rod pins). Once the crank was spun, it was evident that additional weight was needed at both front and rear counterweights. Using heavy tungsten slugs (installed horizontally in the counterweights) 100g was added to the front counterweight and 36g to the rear counterweight.
Here Gary of G&G Balancing assembles our bobweights. Each bobweight half is carefully weight-adjusted by adding weight shims.
Here Gary installs a bobweight onto a rod journal. The bobweights are carefully centered onto the rod journals. Adjacent bobweights are positioned 90-degrees apart.
OUR CRANKSHAFT BALANCING BOBWEIGHT DATA:
Rod big end……… 578 g Piston………………………… 505 g
Rod bearing………+ 48 g Pin…………………………… 151 g
Total……………… 626 g Locks………………………… 3 g
X rods/throw…….. x 2 Rings………………………… 53 g
Total……………… 1252 g Rod small end………………. 245.5 g
Oil…………………+ 5 g Total reciprocating weight = 957.5 g
Rotating weight….= 1254 g
Rotating weight plus reciprocating factor = 2211.5 g
Bobweight = 2211.5 g
With all bobweights installed (this simulates the rotating and recirprocating forces that the crank will experience during operation), the crank is spun to allow the balancing machine to determine what, if any +/- weight corrections are needed to achieve a near-zero dynamic balance. Near in mind that there is no such thing as a “perfectly zero balanced” crankshaft. While it is possible to achieve zero or near-zero on the balancing machine, dynamic forces that occur during normal engine operation present a number of variables that will affect the ever-changing balance condition (parasitic oil that clings/slings from the moving components, engine speed and load, etc.). Basically, you balance the crankshaft to as close to zero as you can without driving yourself nuts. Naturally, the higher the anticipated engine speed and speed/load fluctuations, the more critical the state of balance. For a street engine (yeah, even one that only gets hammered on occasion), balancing to within 4 grams or so will likely be just fine. For a high-rev race engine, especially one that’s equipped with a dry sump oiling system, then it’s more practical to further fine-tune balance to within a margin of about 2 grams. Folks may debatwe this issue, but you simply need to undretand that operational force variations will affect balance in certain RPM/load conditions. If you’re framing out your balancing job, don’t get your shorts in a twist if the low-speed balance isn’t dialed exactly to zero.
OUR CAMSHAFT
We decided to stick with a flat-tappet solid lifter cam, from Comp Cams. This is P/N 33-245-4, Grind No. 282S
Our bumpstick of choice for this build is a Comp Cams flat-tappet hydraulic unit. Noice the Comp lifters, which feature a circumferential groove for better oiling. Especially when using a flat-tappet cam, it’s always best to use the lifters that are recommended by the cam maker.
CAM CARD DATA
Valve adjustment……………….0.022″ intake; 0.022″ exhaust
Gross valve lift………………….0.571″ intake; 0.571″ exhaust
Duration @ 0.015″ tappet lift….282 deg intake; 282 deg exhaust
Valve timing @ 0.015″ OPEN CLOSE
INT 35 BTDC 67 ABDC
EXH 75 BBDC 27 ATDC
Cam installed at 106.0 deg intake centerline:
Duration @ 0.050″……….235 deg int; 235 deg exh
Lobe lift…………………..0.3310″ int; 0.3310″ exh
Lobe separation…………..110.0 deg
OUR CRANKSHAFT
For this build, we chose a Scat high-quality cast crank, P/N 9-FE-4250-6700-2200. This features a 4.250″ stroke, with 2.200″ diameter rod pins (to accept bigblock Chevy rods), designed to accommodate 6.700″ rods. The Chevy BB rods are a good choice, as the smaller big ends provide additional rod-to-block clearance in a stroker setup. FYI: the Ford OE Lemans connecting rod big ends measure 4.070″ wide at the parting line area, while the Scat BBC rod big ends measure 3.763″ wide at the parting line area.
Our Scat stroker crank is a thing of beauty, machined to spec with a fine-tooth comb.
OUR CONNECTING RODS
These are also from Scat. Our rods are forged steel, featuring 6.700″ center-to-center length, designed to accommodate 2.200″ rod journals, and feature 0.9905″ diameter pin bushings. Oil clearance is 0.0005″, since our Diamond wrist pins feature a 0.990″ diameter.
The Scat forged rods feature a 6.700″ center-to-center length. In combination with our 4.250″ crank stroke and custom Diamond pistons, we’ll achieve a zero-deck on this particular block.
OUR HEADS
We salvaged a pair of Ford OE medium-riser iron heads that feature 89cc chambers. These heads feature casting number C5AE-F. These heads feature 89cc chamber volumes. Intake ports measure 1.323: wide (average) x 2.068″ high. Exhaust ports measure 1.268″ wide x 1.815″ high..
The heads were reconditioned and assembled with Manley 2.190″intake (P/N 11884-8) and 1.750″ (P/N 11825-9) exhaust valves.
OUR ROCKER ASSEMBLY
This is a shaft-mounted roller rocker setup from PRW, their part number 3339022 Platinum Series rocker arm kit. Rocker arm ratio is 1.75:1. Features include bronze trunion bushings, rocker-tip-to-valve tip alignment spacers, hardened shafts, 4 single and 4 double 6061 T-6 billet aluminum standoffs, shaft stand-to-head studs, ball style lash adjusters, and even includes a pair of adjustable pushrod checkers.
Why use the antiquated Ford shaft rocker system when a vastly superior aftermarket system is readily available? For this build, we chose a way-cool billet-stand roller rocker shaft setup from PRW.
The PRW shaft rocker system features everything you need, including adjustable ball tips, rocker alignment spacers, rocker stand studs, and even a pair of adjustable pushrod checkers for determining custom pushrod length.
OUR PART NUMBERS
Scat cast crankshaft (4.250″ stroke w/2.200″ rod pins)……9-FE-4250-6700-2200
Scat 6.700″ connecting rods……………………………….2-1CR6700-7/16
Diamond pistons (1.320″ CD)……………………………..Custom-order, job no. 49778
PRW shaft roller rocker kit…………………………………3339022
PRW 7.000″ crank damper………………………………….2539001
Comp Cams flat-tappet solid lifter cam kit…………………33-245-4 Grind No. 282S-10
Comp Cams solid flat tappet lifters…………………………835-16
Comp Cams valve springs…………………………………..972-16
Comp Cams retainers……………………………………….741-16
Comp Cams locks…………………………………………..612-16
MAHLE-Clevite main bearings…………………………….MS-863P
MAHLE-Clevite rod bearings…………………………….. CB743HN
MAHLE-Clevite cam bearings……………………………..SH-781S
MAHLE-Clevite Victor gasket set………………………….FS3389VJ
MAHLE-Clevite Victor head gaskets………………………5959SC
ARP main cap bolt kit………………………………………155-5201
ARP cylinder head bolt kit………………………………….155-3601
ARP carb stud kit……………………………………………400-2402
ARP oil pan bolt kit…………………………………………455-1802
ARP distributor stud & nut………………………………….450-1702
ARP balancer bolt kit……………………………………….150-2501
ARP intake manifold bolt kit………………………………..455-2002
Melling oil pump…………………………………………….M-57HV
Milodon oil pickup…………………………………………18370
Milodon oil pan……………………………………………..31130
ARP oil pump intermediate shaft…………………………..154-7902
Timing cover ……………………………………………OE Ford, reconditioned
PRW also offers a precision fluid-damped version of the crank damper. Timing marks are etched and wfilled in with white and are easy to read.
CAMSHAFT INSTALLATION
After the block was thoroughly hot-washed, rinsed and dried (and the cylinder bores and lifter bores immediately coated with 30W engine oil to prevent surface rust), the cam bearings were final-checked for cleanliness.
The camshaft was rinsed with alcohol and carefully checked for cleanliness. The lobes were then coated with a liberal amount of Comp’s cam and lifter lube (supplied with the cam). I then coated the cam journals with Royal Purple Max Tuff assembly lube (I also coated the cam bearing faces with Max Tuff).
Here Comp Cams assembly lube is applied to the camshaft lobes. It’s a good idea to use the specific assembly lube supplied by the cam maker. I coated all cam journals with Royal Purple Max Tuff assembly lube.
In order to ease camshaft installation, I prefer to coat the rear half (lobes and journals) first, then install the cam halfway, then finish applying lube to the remaining journals and lobes. This makes cam handling a tad bit easier. Of course, extra care is needed to prevent the cam from accidentally slipping off of the cam bearings in the process.
The Comp Cams lube is nice & sticky and won’t drip off of the lobes prior to engine firing. This type of high pressure lube will aid in lobe and lifter mating surface protection during break-in. Never use just any lube on a new flat-tappet camshaft or lifters. Only use a lube that is specifically designed for high pressure protection for flat-tappet camshafts.
Note: In my opinion, you should always use the camshaft lobe assembly lube that is supplied or recommended by the cam maker. This will help avoid any flat-tappet cam break-in failures. Comp also offers its own break-in oil additive, which is high in zinc phosphate (this additive should always be added to the engine oil supply prior to initial break-in and with every subsequent engine oil change).
Using a 6″ long cam snout bolt to aid camshaft handling, I carefully inserted the camshaft into the cam tunnel. Always exercise caution and move slowly whenever installing a camshaft, to prevent nicking or scratching the cam bearings, since scratches on the bearing faces can result in a decrease in oil pressure.
Once the camshaft was fully seated, I final-checked for smooth camshaft rotation. A retainer plate is then installed onto the block face that captures the camshaft. The plate is secured with two 7/16″ x 14 x 5/8″ button head bolts. Apply thread locker to the threads, and install the bolts, tightening to a final value of 40 ft-lbs.
Once the camshaft has been fully inserted, check for ease of camshaft rotation. The cam should rotate like butter. If it won’t, yank it out (carefully) and re-check cam bearing clearance. If cam bearing edges need to be “shaved,” the block should be washed again before you continue with assembly.
The round Ford camshaft centering washer is installed onto the cam nose, and the camshaft retainer plate is then installed onto the block face. This provides both a centering guide and a thrust-stop for the cam.
The OE retainer plate will only install in one orientation for proper hole alignment.
The retainer plate is secured with two grade 8 7/16″ button-head bolts. Be sure to apply thread locking compound to the bolt threads before insertion.
Certainly by this time, engine builders are aware of the reduced zinc phosphate engine oil issue that plagued the industry during the last few years. In addition to using the cam maker’s recommended assembly lube during camshaft and lifter installation, it is absolutely imperative to break-in any flat-tappet camshaft with engine oil that contains the critical level of ZDDP (the high pressure zinc phosphate materials that flat-tappet cams require). Either use a dedicated break-on oil (Joe Gibbs, Brad Penn, Royal Purple and others now offer this specialty oil), or use the petroleum oil of your choice along with a bottle of a ZDDP concentrate, suich as Comp Cams’ break-in additive. Don’t ignore this! In addition to th break-in issue, you must also add a bottle of this additive with every subsequent oil change (or use a specialty oil that is designed for use with flat tappet engines). The zinc phosphate lvel must remain adequate for the life of the engine, not just for break-in.
CRANKSHAFT INSTALLATION
It’s critical to thoroughly clean the crankshaft immediately prior to installation. Never assume that it’s clean. I cleaned the entire crank with brake clean solvent, followed by a hot soapy water wash and rinse, followed by compressed air drying, followed by solvent, and compressed air drying. With each wash, I ran rifle brushes through each oil passage. The main and rod journals were carefully wiped with lint-free shop towels and closely inspected to verify that no particles or lint remained.
The block’s main saddles were wiped clean and dry (using lint-free towel and fast-evaporating solvent). The main bearings and main caps were carefully cleaned as well. The upper main bearings were installed (keeping the same order as during test fitting). The lower main bearings were installed onto the main caps. The upper rear main split seal was oiled and installed into the block’s rear main seal groove, making sure that the seal’s groove faced forward. It’s easy to install these rear main split seals backwards, so pay attention. The large lip and small groove should face forwards towards the engine.
Once all five upper main bearing and the rear split seal half are in place, lubricate the bearing faces. I applied a coating of Royal Purple Max Tuff engine assembly lube. I love this stuff. It’s super-slippery, and it clings, which is nice for an engine that may sit for a while before being fired.
Shown here is the No. 1 main saddle with the oil feed hole slightly chamfered for better flow (we mentioned this in the Part 1 article of this build). Before installing the upper main bearings into the block’s saddles, make sure that the saddles and the rear of the bearings are absolutely clean and free of oil.
Shown here is our block’s No. 2 main saddle with its upper bearing installed. I lightly chamfered the entry edge of the bearings as well, on the opposite side of the saddle hole chamfer. This will aid in more efficient oil flow to the bearing.
Our Clevite 77 main bearing set. Whenever you prepare to install main or rod bearings, each bearing (and each block and main cap saddle) must be checked for cleanliness. While these bearings were clean and sealed in plastic when boxed at the factory, dirt, fine shop particles, oil, etc. may have contyaminated them during your handling. Carefully inspect each for dust and oil. Use a lint-free clean shop towel. Make certain that there is no oil on the backside of each bearing shell.
Main bearings such as these Clevite 77s provide excellent crush factor and oil wedge ramping for efficient oil film support of the crankshaft. Let them do their job…make sure that no debris is trapped between the bearings and their respective saddles.
Once the main bearings are in place (uppers in the block saddles and lowers in their caps), only then apply lubricant to the exposed bearing faces. I used Royal Purple Max Tuff assembly lube, although you may have your own preference. I love Max Tuff because this synthetic goo is so super-slippery and it offers outstanding retention. It won’t drip off and leave the bearings dry prior to engine firing, even idf the engine sits around for a long time. Apply the lube and then (using a very clean finger) carefully smear the lube across the entire bearing face (and on the thrust surfaces of the thrust bearing). Regardless of which lube you use, avoid placing lubricant on the cap an block mating surfaces.
With all five upper main bearings in place and lubed, and the upper rear main split seal in place, carefully lay the crankshaft onto the upper bearings. Do not rotate th crankshaft at this time to avoid oozing lube onto the main cap mating surfaces.
Before installing the main cap bolts, apply a proper fastener lubricant such as ARP moly assembly lube onto the underside of the bolt head and both sides of each washer, in addition to the bolt threads.
Apply lubricant (again, such as ARP moly) to the main cap bolt threads. This lubricant, as compared to engine oil, provides less frictional resistance during tightening, allowing you to achieve a much more accurate fastener clamping load. Be aware that the use of engine oil or a moly lube demands following specific torque-tightening values. Since the moly lube reduces friction much more than oil, the final torque value for moly will be lower than the value published for the use of oil.
With the FE side-oiler main caps loosely installed, (with the 1/2″ vertical bolts partially threaded and the main caps gently tapped into register), install the main cap side-bolt spacers to their proper locations on caps 2, 3 and 4. Once the side bolts and their spacers are in place (with side bolts partially threaded), you can begin to torque-tighten the primary 1/2″ bolts. Tighten all ten 1/2″ bolts in three progressive stages to full value (using ARP bolts and ARP moly lube, this is 95 ft-lbs). Once all of the ten 1/2″ main cap bolts have been fully tightened to value, the six main cap side bolts are then tightened to a value of 40 ft-lbs.
Once all five upper bearings are lubed, the crankshaft is gently laid into position. Don’t be tempted to rotate the crank yet…you don’t want to push lube onto the main cap mating surfaces.
Before messing with the main caps, make sure that all of the main cap bolts and washers are clean and lubed. I applied ARP moly lube to each bolt…under the bolt head, on both sides of each washer, and on the bolt threads.
Number 1, 2, 3 and 4 main caps (with bearing lubed) are positioned and gently tapped partially into register. As soon as you place a main cap into its location, insert the ½” main cap bolts (leave them loose…do not tighten yet!) to make sure that the cap is square and properly positioned. The placement of the bolts will keep the cap aligned. Gently tap the cap further into its register. Begin to snug the bolts in order to draw the cap closer to the block. Loosen the two main cap bolts and insert the spacers and side bolts at cap numbers 2, 3 and 4. Being careful to keep the cap spacers in proper order, insert a spacer between the cap and block, and loosely thread the side bolt into place. Do not tighten the side bolts yet. Just make sure that they are engaged into the caps.
Before you can begin to tighten any of the 1-4 main cap bolts, prepare and install the rear main cap. Pay attention to the sealing aspects of the No. 5 cap.
Install the lower split seal into the cap’s seal groove (again, grooved side of the seal aiming forward).
The rear main cap also features a vertical angled groove on each side. Two rubber seal strips are provided with the Victor gasket set. However, don’t install these just yet.
Apply a minimal amount of RTV to the chamfered edges of the cap (adjacent to its mating faces), and onto the mating faces, but do not apply RTV to the split seal ends. Don’t go overboard with the RTV. A relatively thin film should do the trick.
Place the cap into position and loosely install the two cap bolts as soon as possible. These will help to guide the cap. Coat each seal stick with oil and insert them into the angled grooves on the sides of the cap. The seal stick should end up flush with the bottom of the cap (the exposed end of the cap). This may be a bit tricky, but use patience. Once inserted a bit more than halfway, insert the small-diameter steel pins (supplied in the Victor set) into the groove at the narrow side of the seal (between the seal stick and the cap). Carefully push/tap both the seal stick and the pin until both are flush with the surface of the cap. This ensures that the seal sticks protrude a bit at the mating surface side of the cap for a slight crush sealing effect. Now all main cap bolts may be tightened.
You’ll tighten all of the ½” (vertical) main cap bolts first, followed by the six side bolts. The primary (vertical) bolts are to be tightened in three steps, beginning with a value of 20 ft-lbs, followed by 55 ft-lbs and finally 95 ft-lbs. The side bolts will be tightened to 40 ft-lbs. Bear in mind that these torque values are based on using ARP bolts, and with all bolts coated with ARP moly lube. If you use engine oil on the bolts instead of moly, the final torque value of the primary bolts will be about 105 ft-lbs. The use of ARP moly is recommended (instead of oil), since this lubricant reduces the head/washer/thread friction factor, allowing you to achieve a more accurate and consistent bolt clamping load.
MAIN CAP TIGHTENING SEQUENCE
MAIN CAP NUMBER ½” BOLT LOCATION
3………………………………….LEFT
3………………………………….RIGHT
2………………………………….RIGHT
2………………………………….LEFT
4………………………………….LEFT
4………………………………….RIGHT
1………………………………….RIGHT
1………………………………….LEFT
5………………………………….LEFT
5………………………………….RIGHT
MAIN CAP SIDEBOLT LOCATION
CAP NO. 3……………………….LEFT
CAP NO. 3……………………….RIGHT
CAP NO. 2……………………….RIGHT
CAP NO. 2……………………….LEFT
CAP NO. 4……………………….LEFT
CAP NO. 4……………………….RIGHT
In the next article installment, we’ll discuss installation of the remote oil filter adapter to the block, and completion of the short block assembly including connecting rods, pistons, rings, rod bearings and camshaft timing.
Tags: ARP, BALANCE, BEARINGS, BOBWEIGHTS, CAM CARD, CAM INSTALLATION, CAMSHAFT, COMP CAMS, CONNECTING RODS, CRANKSHAFT, CRANKSHAFT INSTALLATION, CYLINDER HEADS, DIAMOND PISTONS, MAHLE CLEVITE, MAIN CAP TIGHTENING SEQUENCE, MAIN CAPS, MANLEY, MELLING, MILODON, PART NUMBERS, PRW, ROCKERS, ROYAL PURPLE, SCAT
