If a big-block Chevy has not figured into your life yet, you probably won't understand it until you experience the apparent ease with which it will deliver a big fat output. Whereas a small-block always seems so busy on the dyno, a big-block just grunts it out, seemingly without any real effort. Adding a blower to a big-block just reinforces the whole "in your face" deal. Apart from the intimidation factor, the effortless output was why Outlaw Racing customer Alex Maldonado chose to go the blown big-block route for his '57 Chevy-it's a big, heavy car. With a basic game plan in mind, it was time for Alex to do some source searching.

Anytime we talk blown big-block, the word "budget" can no longer be used with the word "low." But that should not imply a build cost looking like a monetary black hole either. Choose an engine builder who has expertise at off-the-shelf parts selection for functional combinations, and an exotic "catalog" big-block like this one could be yours for under $21,000. But for many, $21,000 is still a lot of cash. That said, it becomes even more important to choose a reputable engine builder who has experience with such builds, and one who stands behind his work.

Andy Mitchell is the boss at the Upland, California-based Outlaw Racing Engines. It has to be said that it's easy to stick the word "Racing" into a company business name. Sometimes for the business' owner, it's no more than a flight of imagination. When contemplating an exotic high-performance engine where $21,000 is involved, success on the track looks like it should figure prominently in the decision making. Visit www.outlawracingengines.com, and you will see some of the race-winning, record-setting cars powered by Andy's engines. With a clean, smart, well-equipped full-service shop to back his efforts, Alex figured Andy looked like the guy to build his engine.

The Bottom End
A few years back, the big-block Chevy went through a popularity resurgence. This has resulted in even stock-blocks commanding premium asking prices. We have just gone through this routine ourselves, shelling out $600 for an average core 454 block. By the time we found a good late-model block, and had it machined, the bill was well into four figures. At the end of the day, we still only had a stock block. Andy's advice here is spend the money, get a Dart block, and enjoy the insurance of super strength that goes with it. For something over a grand more than stock, you get a new block with a 4.5-inch bore that will go to 4.625 if necessary. That's up to 3/8 inch bigger than stock. Additionally, the block is good for a couple of thousand horsepower, and then some. It also has the sort of reliability enhancing upgrades you would like to have on a stock-block, such as priority main oiling (unlike stock, oil is delivered to the mains first, then lifters). Also, a re-routed oil crossover passage eliminates internal oil leakage at the distributor.

For a crank, a Callies Dragonslayer was chosen. These are best described as an all-American-made, heavy duty sportsman crank. Callies makes these cranks with a stock 2.200-inch rod journal, with stroke options of 4.000, 4.250, and 4.500 inches. With top-grade 4340 steel, a tough core, and deep-case heat treat, these cranks are about ready for anything. For shock-and-awe value, it has the ability-if required-to turn a lot of rpm. In this case, the 4-inch stroke was used, and with the 4.5-inch bore, delivered 509 inches.

Rods for this 509 took the form of a set of Howards billet BR series. This American-made 6.8-inch long two-rib cap design is (at a shade over 780 grams) lighter than you would expect of a heavy-duty rod. Riding on the rods is a set of JE's finest. These off-the-shelf pistons worked out perfectly in the tall-deck Dart block, with the 4-inch stroke and the 6.8-inch-long Howards rods providing a respectable 1.395-inch compression height. Keeping the wristpin out of the oil ring on a street engine of this power level will pay dividends in longevity for years to come. With the 28cc dish pistons just shy of flush, plus a flat mill of some .010 inch on the heads, resulted in a boost-friendly 8.2:1 compression ratio. With a compression ratio this conservative, there was room to considerably move the boost in an upward direction at a later date. The JE pistons were equipped with Total Seal Advanced Profile Gapless stainless steel rings to ensure a long life and gas-tight seal when that boosted charge lights off. Total Seal rings are, among some engine builders, a controversial subject. Andy's viewpoint: "We go faster with them, and our team car is slaughtering the opposition on the track."

Feeding the internals the necessary oil flow and pressure was a Melling high-volume pump, and to control the inevitable oil surge from high g acceleration, a six-quart pan from Big B Auto was used.

Power Production Parts
We can liken the bottom end of this engine to a "case." And with the parts used, we have a case that can reliably contain the pressures and mechanically generated dynamic forces that are likely to come about during the business of producing immense power figures. It's time to look at just what power producing components Andy chose for this build.

Starting at the top is a pair of blower-spec 750 Holleys, which will be fed a diet of clean air courtesy of a Hilborn filter-equipped air scoop. Good filtration will ensure the close tolerances of the blower rotors are not compromised, and the rings and bores will have long lives.

The 750 Holleys used were of a blower-specific design. The main difference is the power valve is referenced to the manifold vacuum/pressure under the supercharger, not the area under the carbs before the supercharger. As far as the fuel delivery curves at part and wide-open throttle are concerned, Holley went through a series of calibration tests at its facility on these Weiand 6- and 8-71 blowers. An advantage of the calibration of a blower carb is that possible calibration changes, from one blower to another, are very minimal, as the induction pulses are unique to the blower, not the engine. This means once the factory calibrations are done, they won't change significantly from one GMC-blown application to another.

Because the form and amplitude of the blower pulses are measurably different than piston-induced pulses in a normally aspirated engine, the fuel delivery calibrations for these blower carbs are substantially different. To achieve the desired fuel curves in idle, transition, and wide-open mode, the main jets, air correctors, and emulsion well holes had to be re-evaluated. Just how well these near-universal calibrations would work would be revealed when this 509 hit the dyno.

The Blower
Ultimately, it's the presence of that big 8-71 blower that gives this 509 its menacing appearance and sound. Originally designed as the scavenge pump for a GMC two-cycle diesel, this blower found notoriety when the top Gas and Fuel dragster guys started using it in the late '50s and early '60s. It has long gone out of production, and what Weiand now builds is an updated version from all-new tooling. It is in fact an improved replica of the world's most notorious blower, and falls into a category known as a "positive displacement" supercharger. If we exclude leakage past the rotors, that means (unlike a turbo) it moves a certain number of cubic feet of air per revolution, regardless of rpm. What this does is not only produce boost everywhere in the rpm range, but also produces it instantly, on demand. When everything is just right, throttle response follows suit, meaning that it's near instant. You have to believe those Top Fuel guys used this blower all those years for a reason. Maybe it's because it made them fast!

Heads
Although iron heads can be used with a supercharger, aluminum heads have the advantage of running cooler, and with less troublesome detonation-inducing hot spots. This means they are able to accommodate a combination of more boost and higher compression. The heads chosen for the job were as-cast RHS 320cc port heads (PN 11001). These are the smaller of the two port sizes that RHS offers for the big-block. When a blower factors into the equation of a high-output street motor, the port size does not need to be configured so much for the top end output because the blower will, to a certain extent, take care of that with boost. For part-throttle driveability, there are advantages toward the use of a smaller port, and that is why this particular spec of head was chosen.

PRO ACTION CYLINDER HEAD FLOW
RHS 320CC ALUMINUM HEADS
Valve Intake Intake Exhaust
lift: CFM (Poor): CFM (Good): CFM:
.050 37 38.6 29.3
.100 72.2 73.6 60.5
.200 131 129 114
.300 191 186 156
.400 248 238 193
.500 296 286 224
.600 320 330 252
.700 328 356 276

Valvetrain
Alex wanted a ruthlessly fast street machine, not an all-out racer. That meant selecting a hydraulic cam that was spec'd to deliver good idle, with a touch of mean race-engine lope. The cam spec developed by Andy uses COMP's popular Xtreme Energy hydraulic roller profiles. For a street cam, the intake (PN 3370) has a seemingly huge 303 degrees of off-the-seat duration. The exhaust profile (PN 3371) has 309 degrees, and at .050-inch lift, the cam lobes deliver 248 and 254 degrees duration, respectively.

Unlike a solid roller, these COMP Xtreme profiles have a relatively gentle initial opening, so compared to a solid roller with the same off-the-seat duration, they act a lot shorter. Once these profiles have taken up all the valvetrain preload, they get with the program. Another key factor for a big-block Chevy cam is having a respectably high valve lift. With the .380-inch lobe lift from these profiles, a valve lift of .646 inch is generated with the 1.7 ratio PRW stainless roller rockers used. Also working toward streetability is the fact that a blower-spec cam should, along with slightly less advance, have a wider lobe separation angle than the equivalent optimally spec'd cam for a normally aspirated engine. Too much overlap means the boosted intake charge will not only scavenge the combustion chamber, but go right on out the exhaust port. The wide 114-degree LCA chosen by Andy has a significant influence toward making the cam more civilized for the street. With the 114-degree LCA, the overlap is a very streetable 78 degrees. To give you small-block guys a reference point, it would be like running a hydraulic flat-tappet cam of 284 off-the-seat degrees in a 350. It's big, but far from outlandish.

The business of transmitting the cam motion to the valves starts with a set of COMP's plus .300-inch-long Pro Magnum hydraulic rollers. The extra lifter length here is needed to clear the Dart block's taller lifter bores. The lifter motion reaches the rockers via a set of Manley 3/8-inch diameter pushrods. The rockers are PRW's ultra-stiff stainless items, which unlike aluminum rockers, have a virtually infinite fatigue life. This makes them good for the street where millions of cycles are involved.

Springs for a hydraulic valvetrain can be critical. Too little seat pressure and seat bounce can rob an unbelievable amount of power. Too much, and the hydraulic internals of the lifter can collapse. Andy's choice of spring, a COMP 930, proved to be right on the money. With 153 lbs on the seat, and 382 lbs over the nose, the valvetrain ran flawlessly to the desired 6,600 rpm.

HYDRAULIC ROLLER CAM SPECS
COMP Serial No.: K 6085-07
Grind: CB 3370B/3371B HR114+2
Gross valve lift: .647/.647
Duration @ .006: 303/309
Duration @ .050: 248/254
Lobe lift: .381/.381
Lobe separation: 114 degrees

Ignition
Last item on the build is the ignition system. Andy used an MSD Pro Billet distributor with fixed timing. This might just have the scent of something a little too race-orientated, but the fact of the matter is that often a blown engine with a long-period cam has an advance curve requirement that is nearly a straight line. This engine falls into this category. The key issue to address is for the distributor to deliver a really healthy spark (not to mention physically clear the blower, which is in close proximity to the distributor).

Dyno Time
After a suitable break-in time, the 509 was given a nut-and-bolt service. This entails a check for any nuts/bolts that may have unseated after the break-in heat cycle. With that done, it was time to feed in a 50/50 mix of 114 octane with pump gas, and get acquainted with this engine's personality. It didn't take much in the way of running to establish this was the real deal. If Holley's claim that the carb calibration was a dead match for the blower, we'd soon find out. Those Holley's weren't close-they were right on. The only carb adjustment required was to set the idle adjustment screws and idle speed.

Because the carb calibration was on the money, this left only timing optimization. Andy started the tests at 28 degrees, as this was considered a really safe advance for an engine of this compression and boost, which registered a peak of 9.6 psi.

A run at 30 degrees netted more of everything, so 32 degrees was tried, and this proved a little better yet. Thirty-two degrees is quite a lot of timing for a blower motor, but when the very conservative compression ratio and boost are factored in, that number falls into place nicely. The bottom line here is that this engine could well deal with a blower overdrive that delivers as much as 15 lbs of boost.

With the ignition timing set, this 509 was almost a contradiction in terms. It ran like a super-loud 850hp Swiss watch. Everyone was impressed with the way the Holley carbs performed. Andy commented that it would be hard to imagine that fuel injection would be any better than these blower carbs. The steady transition from small-part throttle cruise to a relatively wide-throttle position was smooth, and free of the lean stumble sometimes seen in non-blower-specific carb setups. As for throttle response, this was like watching a stick of dynamite go off at a safe distance. It made no difference how fast the throttle was opened, the engine kept up. The response was, in fact, so fast that the torque reaction looked like it would cause the engine to leap off the dyno stand. There were smiles all around, and especially on engine owner Alex's face. Is almost 850 hp going to be fast enough? Alex says: "Speed is relative. I just need to be faster than my relatives!"

ENGINE SPECIFICATIONS
509ci Weiand 8-71 BBC
Bore: 4.500 inches
Stroke: 4.00 inches
CID: 509 ci
Engine block: Dart Big M tall-deck
Compression ratio: 8.2:1
Fuel octane: 50/50 mix, 91 pump gas
and 114 race gas
Camshaft: 248/254 at .050, .647/.647-inch lift
Camshaft type: hydraulic roller
Cam drive: Summit, double roller
Rockers: PRW, 1.7 ratio stainless
Springs: COMP, 930-16 dual w/damper
Seat load: 153 lbs
Open load: 382 lbs
Top ring: gapless, stainless steel, 1/16 inch
Top ring gap: .032 inch
Second ring: napier, 1/16 inch
Second ring gap: .028 inch
Oil ring: 3/16 inch
Piston: JE forged, 28cc dish,
1.395-inch compression height
Quench clearance: .005-inch
Crankshaft: Callies Dragonslayer,
forged 4340, 4-inch stroke
Main journal dia.: 2.749 inches
Rod journal dia.: 2.200 inches
Connecting rods: Howards billet steel, 6.800 inches
Cylinder heads: RHS Pro Action 320cc aluminum
Intake runner volume: 320cc
Peak intake flow: 356 cfm
Peak exhaust flow: 276 cfm
Intake valve diameter: 2.25 inches
Exhaust valve diameter: 1.88 inch
Induction: Weiand 8-71 supercharger
Carburetion: twin Holley 750-cfm blower carbs
Headers: 2 1/8 inches
Ignition: MSD Pro Billet distributor,
MSD Digital 7 (dyno)
Oil pump: Melling, high volume
Oil pan: Big B Auto, six quart fill
WHERE THE MONEY WENT
Part: Source: Part No.: Price:
Big M tall-deck block Dart/Summit DRT-31273454 $2,204.95
Head stud kit Dart/Summit DRT-64210240 $91.95
Oil filter adapter AA Midwest OFA305 $9.50
Timing cover Big B Auto 8422 $40
Oil pan Big B Auto 9729 $70
Oil pickup Big B Auto 9730 $12
Oil pump Melling/Summit MEL-M77HV $32.95
Oil pump stud kit ARP/Summit ARP-230-7003 $5.88
Oil pump shaft Melling/Summit MEL-IS-77A $9.39
Main bearings Clevite/Summit CLE-MS829H $73.95
Rod bearings (need 8) Clevite/Summit CB743HN $79.60
Cam bearings Dura-Bond/Summit DUR-GMP-12LT $71.39
Dragonslayer 4.00-inch forged crank Callies/Doug Herbert CALBB042-B-DS $1,019.99
6.800-inch billet steel rods Howards/Competition Products BR6800 $879.95
Forged 28cc dish pistons (1.395-in CH) JE/Summit JEP-257947-8 $798.95
Advanced Profiling gapless ring set Total Seal/Summit TSR-GAPLESS01-08 $369.69
Cylinder head stud kit ARP/Summit ARP-235-4303 $165.95
Four-bolt main stud kit ARP/Summit ARP-235-5701 $118.95
Cam bolt kit ARP/Summit ARP-134-1001 $4.88
Intake manifold bolts (3/8 x 2 inch Allen) local hardware n/a $15
RHS 320cc cylinder heads (bare) RHS 11001 $1,814.62
2.25-inch intake valves (8) Manley/Summit MAN-11856-8 $183.60
1.88-inch Inconel exhaust valves (8) Manley/Summit MAN-11743-8 $319.60
Valvesprings (set) COMP/Summit CCA-930-16 $139.95
Spring seats (1.55-inch OD) COMP/Summit CCA-4776-16 $41.88
Retainers (set) COMP/Summit CCA-741-16 $54.95
Valve locks (-.050-inch) COMP/Summit CCA-630-16 $37.99
Rocker studs COMP/Summit CCA-4512-16 $66.69
Guide plates (set of 8) COMP/Summit CCA-4806-8 $41.95
Rocker arms, 1.7 ratio PRW/Pace Performance PRW0245402 $246.15
Pushrods (int.), 3/8 x 8.575-inch Manley/Summit MAN-25858-8 $102.39
Pushrods (exh.), 3/8 x 9.550-inch Manley/Summit MAN-25955-8 $102.39
Hydraulic roller lifters, plus .300-inch COMP/Summit CCA-8954-16 $578.39
Custom hydraulic roller cam COMP/Summit CCA-11-000-8 $255.95
Cam button COMP/Summit CCA-205 $8.39
Timing set Summit G6610 $37.95
Gasket set (conversion) Fel-Pro/Summit FPP-17140 $46.99
Head gaskets (need 2) Fel-Pro/Summit FPP-1017-1 $79.90
Intake spacer kit for tall deck block Weiand/Summit WND-8204 $159.95
Intake gaskets (need 2 sets) Fel-Pro/Summit FPP-1275 $31.90
Exhaust gaskets (pair) Fel-Pro/Summit FPP-1412 $17.95
Viton rear main seal Fel-Pro/Summit FPP-2918 $23.95
8-71 blower kit Weiand/Summit WND-7186 $2,919
Blower idler bracket Weiand 7070 incl.
Accessory drive crank pulley Weiand 7113WIN incl.
Blower drivebelt (75mm x 1440mm) Weiand 71100WIN incl.
Crank pulley pilot bolt kit Weiand 7038 incl.
3.5-inch idler pulley assy. Weiand 7027 incl.
1-inch pulley spacer Weiand 7106WIN incl.
54-tooth x 3.5-inch pulley Weiand 7109-54 incl.
61-tooth x 3.5-inch pulley Weiand 7109-61 incl.
Dual 750-cfm blower carbs (need 2) Holley/Summit HLY-0-80576S $1,499.90
Fuel line kit Weiand/Summit WND-7093 $319.95
Throttle linkage kit Weiand/Summit WND-7166 $179.95
Hilborn air scoop w/filters Weiand/Summit WND-7221 $259.95
Pro Billet distributor MSD/Summit MSD-85551 $232.90
Spark plug wires (Taylor '409') Taylor/Summit TAY-79232 $109.69
Spark plugs (need 8) NGK NGK-5238 $19.20
Valve covers (pr.) Outlaw Racing VCOutlaw1 $325
Valve cover gaskets (pr.) Summit SUM-G2311 $13.95
Electric water pump Summit SUM-314454 $223.95
Timing pointer Summit SUM-164800 $24.95
Transmission dowel set Tavia 02700 $8.80
Chevy orange engine paint Dupli-Color/Summit SHW-DE1607 $4.95
Parts subtotal: $16,610.54
Machine Work:
Cylinder head prep (hone guides, face valves, shim, assembly) $165
Surface heads $80
Hone block with torque plates $185
Balance rotating assy. $185
Engine assembly $2,000
Dyno tuning $850
Labor subtotal: $3,465
Total: $20,075.54
DYNO NUMBERS
509CI WEIAND 8-71 BIG-BLOCK CHEVY
Drive pulley: 61 tooth
Blower pulley: 54 tooth
RPM TQ HP BOOST PSI
4,500 768 658 7.2
4,600 765 670 7.3
4,700 767 686 7.3
4,800 768 702 7.4
4,900 765 714 7.5
5,000 762 726 7.6
5,100 756 734 7.7
5,200 749 742 7.7
5,300 746 753 7.8
5,400 746 767 7.9
5,500 739 774 8.0
5,600 736 785 8.2
5,700 728 790 8.3
5,800 724 800 8.5
5,900 720 809 8.7
6,000 718 820 8.8
6,100 712 827 8.9
6,200 704 831 9.0
6,300 698 838 9.2
6,400 691 842 9.2
6,500 686 849 9.4
6,600 675 848 9.6
SOURCE
Competition Products
N/A
Federal-Mogul/Fel-Pro
Dept. MPRM, P.O. Box 1966
Detroit
MI  48235
248-354-7700
Total Seal
Phoenix
AZ
800-874-2753
totalseal.com
Melling Engine Parts
2620 Saradan Dr.
Jackson
MI  49202
517-787-8172
www.melling.com
NGK Spark Plugs
Wixom
MI
www.ngksparkplugs.com
Automotive Racing Products (ARP)
531 Spectrum Circle
Oxnard
CA  93030
805-278-7223
Tavia Performance Products
Garden Grove
CA
Big B Auto
www.bigbauto.com
AA Midwest/Enginequest Doug Herbert
www.dougherbert.com
Dupli-Color
www.duplicolor.com
Holley/Weiand
2-70/-781-9741
www.holley.com
Pace Performance
888-748-4655
www.paceperformance.com
COMP Cams
Taylor Cable Products
301 Highgrove Rd
Grandview
MO  64030-2201
816-765-2452
Performance Racing Warehouse (PRW)
Orange
CA
Summit Racing
P.O. Box 909
Akron
OH  44309-0909
800-230-3030
www.summitracing.com
Dart Machinery
353 Oliver St.
Troy
MI  48084
248-362-1188
www.dartheads.com
Outlaw Racing Engines
909-931-4612
JE Pistons
MSD Ignition
El Paso
TX
9-15/-857-5200
msdignition.com
Howards Cams
280 W. 35th Ave.
Unti #2
Oshkosh
Wi  54902
www.howardscams.com
Westech Performance Group
11098 Venture Dr., Unit C
Mira Loma
CA  91752
9-09/-685-4767
www.westechperformance.com
Manley Performance Products
Lakewood
NJ
732-905-3366
www.manleyperformance.com
Mahle Clevite Inc. Racing Head Service (RHS)
8-77/-776-4323
www.racingheadservice.com
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