622 HP Blown Street Small Block
Sometimes a simple straightforward combination is best for a particular application. No tricks, no overly exotic hardware; just regular hardcore speed equipment built around a standard Gen 1 small block for a traditional street rod or street machine. These are the bread and butter engines that any hot rodder would love to have in his personal ride. A blown small block with twin Holley carbs, 600+ horsepower and all the requisite bling to ensure the proper first impression as conveyed by all the shiny hardware and the sweet sound of blower whine announcing your approach.
Over at Hardcore Horsepower in Franklin, Tennessee, owner Mike Petralia meticulously assembled this 383ci Chevy small block topped with a highly polished 6-71 Weiand supercharger and a pair of 600 FM Holley blower carbs plumbed with a beautiful set of hard lines. Now there's an engine that would look great in just about any engine compartment and one with the grunt to back up its good looks. Some might say, "Oh, I know a guy that's got 750 horses from the same setup." Well, no you don't, but you may have heard that somewhere. Sure there's somebody out there twisting it a little faster, boosting it a little higher but why?
Once you pass 500 horsepower with conventional hardware the engine's start getting a little harder to manage and you're always chasing the tune. 500 horsepower will blow the tires completely off of just about anything you put behind it so why not settle for a little less and really boost the durability and drivability. Little things like a stable idle and crisp throttle response combined with the power adder's smooth contribution of power make a tremendous difference in a vehicle you drive for pleasure. The specimen you see here delivers 622 horsepower on pump gas and 619 lb-ft peak torque at 4300 rpm. In fact it holds 575 lb-ft or better from 3200 through 5700 and that makes for quite a ride.
Many engine builders have pet combinations that they have found reliable for specific applications. No exception, Petralia has identified a specific mix of components (see spec sheet) that he knows will survive even if the customer chooses to lean on the motor much harder or turn up the boost later. Builders don't like complaints or come backs so they go to great lengths to make certain that their products perform and live well in today's performance environment which includes high operating temperatures and often poor quality fuel.
If you study the accompanying dyno sheet and graph you'll see that the engine delivers more than 575 lbs_ft of torque at a mere 3000 rpm on pump gas; more than enough to shred the tires on any street machine or street rod of your choice. Petralia prides himself on striking the proper balance between good power, drivabillity and long term durability with minimal maintenance. These roots style blowers take more power to run and they create more heat than more contemporary supercharger setups, but that's okay because they've got the look and feel you need for hot street profiling.
One thing we find particularly interesting is the accompanying photo of the complete engine on a scale. Note that it weighs in at less than 500 pounds. Now new LS based engines might beat that a bit, but 500 pounds is not bad for an iron block Gen 1 small block thumping out well over 600 horses. Many LS builders are working from iron block versions anyway so they're not likely to be much different from this. Check out the detailed spec sheet below to see the whole combination.
If you're attempting to duplicate this beauty you might try a few substitutions, but why? Mike has already laid out the best combination of power, durability and value. So you might consider calling and having him build one for your hot machine. That way you get guaranteed performance and you don't have to wonder if you really did torque the bolts on the number eight rod. Know what I mean Gene?
Mike Petralia's Hardcore Horsepower
High Performance Engine Balance; Neutral/Internal Balance; w/ Heavy Metal
Clevite SBC Main bearings, 350 Std. size, Grooved Upper Halves, Plain Lower Halves, TM-77, P-Series Performance
Clevite SBC Connecting Rod Bearings, 2.100 Std. size, TM-77, P-Series Performance
Engine Block; SBC GEN I Reman Cast Iron, 4-Bolt Mains, 4.030-Bore, 1-pc RMS, fully-machined, stroker clearanced, RH dipstick; includes cam bearings, freeze plugs, and dowel pins installed
*Requires rear main seal + adapter kit; not included
Camshaft; SBC HFT, Blower Grind, .508"/.533" @ 1.5:1, Hardcore Horsepower "Ultra BA620+", idle-6000 rpm
SBC Timing Chain Set; 700-series, dual roller, 3-key adjustable
SBC Timing Cover; HD, 1/3 heavier than stock, stamped steel w/ cam button area, no timing tab, will clear dbl. roller
Comp Cams Chevy SB/BB V8, Black Oxide, Chevy, Big/ Small Block, includes 3 5/16-18 bolts (each)
Holley, 600cfm, Gasoline, Model 4150 2 x 4bbl, 6-71 blower calibration, Universal, Dual Inlet, Silver, w/ Mech choke
Stainless Steel fuel line kit, Dual Holley, Double Pumpers, Side-Mounted, -6AN, Black, Kit
Weiand Throttle Linkage Kit, Dual Quad for 6-71/8-71, 256 Superchargers, Side Mount, Universal
Carb Bolts; 5/16-18 x 1 SOCKET HEAD CAP SCREW S/S w/ WASHER
Carb Bolts; 5/16-18 x 1-1/4 SOCKET HEAD CAP SCREW S/S w/ WASHER
Eagle Connecting Rods; SBC 6.0", I-beam, 4340 forged, 2.100, LT WT, Stroker Profiled, 3/8" ARP 8740 capscrews,
bushed pin end, wt. matched, 590gr
Scat Crankshaft; SBC CEB, 3.75"-S, 5.70" x 2.100"-R, 1-pc RMS, 350-M, Ext Bal, 53-lbs; Cast Steel, Knife-edged
Machine extra 1/4" keyway in crank snout 180° from stock
Pioneer SBC Crankshaft/Woodruff Key, 3/16" x .728" long
Key Stock, 1/4" x 1/4" x 1" long, Hardened, USA-made
Cyl head; SBC 200cc Dart "SHP", 68cc (as measured), straight plugs, no heat riser, 2.02/1.60 valves, 3/8-rocker stud, 1.437" O.D. springs (130# @ 1.800"; 330# @ 1.250"; 364# Rate, 1.080" CB, .620"+ max lift), 23°, Aluminum, complete w/parts (pair)
GM SBC 6-Point Cyl Head Bolt Kit,
SBC MLS head gasket 4.200" x .046", 10.44cc
Powerbond SBC Dampener; 8.0" Ext Balance, Race-Series, SFI 18.1, 10.7-lbs.
Machine extra Keyway in Harmonic Dampener
Mallory Distributor "Max-Fire" Multi-Strike Capacitive Discharge (CD) built-in, Magnetic Pickup, Programmable, Electronic Advance, Boost Retard, 3-Bar MAP sensor built-in, Small Cap, fits: Chevrolet V8 262-400, 396-502
Distributor hold down bracket; Chevy, chrome, steel stud included
Flexplate; SBC Ext. Bal. 1-pc RMS, 168-tooth, SFI-approved
Fuel; 93-octane unleaded pump gas for testing
SBC Fuel pump block-off; Steel, Chrome
Bolts; 3/8-16 x 1 SOCKET HEAD CAP SCREW S/S
Intake Gasket; SBC, Composite, R-port, 2.09 in. x 1.28 in. Port, .060 in. Thick, Set; Fel-Pro
Lifters; SBC Hyd Flat Tappet Hi-RPM Street/Marine, .842" dia. (each) Lunati "Micro-Trol"
Break-In Motor Oil, 15W-50 (quart); Joe Gibbs Driven
WIX Engine Oil Filter, 13/16-16 Thread, 3-5/8" Dia., 5-3/16" Tall, 21-Micron
WIX Racing Engine Oil Filter, 13/16-16 Thread, 3-5/8" Dia., 5-3/16" Tall, 61-Micron
SBC/3.750-Stroke w/ Stock Rods, Stock Capacity Oiling system includes:
- Milodon SBC '80-'85 2-pc rear main seal, 5-Qt low-profile, 3.750"-S, low-profile, 8" deep, welded steel, RH dipstick
- Melling Std Vol oil pump + matching pickup + HD driveshaft
- 1-pc silicone rubber oil pan gasket and fasteners
- ARP SBC Oil Pump Stud, 12-Point Chromemoly
- Engine Works SB/BB Chevy spin-on filter adapter
PCV Valve, 90-deg, inclds hose
Piston SBC; -28cc, 2618-F (4.030"-bore, 3.750"-stroke, 6.000"-rod, 1.125"CH, floating pin, 1/16-1/16-3/16 Plasma-Moly File-Fit rings included, 23°, Wiseco "Pro True"
Pushrod; 5/16" x 7.800" x .080", 4130 chrome moly, hardened, blk oxd
Rear Main Seal; SBC GEN I, 1-Piece, Rubber, 1986-97 5.0L/5.7L, Each; Fel-Pro
Rear Main Seal Adapter; SBC GEN I, 1-Piece, Fasteners Included
SBC Roller Rockers; 1.5:1, Aluminum, 7/16" Stud Mount, w/ Poly-Locks, Set of 16; Warhammer
Autolite Racing Spark Plugs 8
Weiand Supercharger System, SBC 6-71 Series, Polished, 8mm drive, xx.x% drive ratio, (xx/xx pulleys)
Fitting; 5/32" "T" Tube Push-to-Connect, Universal, T Union, 140°-Temp, 145-psi Nylon; (each) Dynaflo
Fitting; 5/32" "Y" Tube Push-to-Connect, Universal, Straight, Union, 140°-Temp, 145-psi Nylon; (each) Alpha Technologies
Fitting; 5/32" Tube x 1/8" MPT, Universal, Straight, Connector, Nickel Plated Brass; (each) Alpha Technologies
Tubing; 5/32" Air Brake Line, (Foot); Gates
SBC Timing Pointer; billet alum; fits 6.25" dampener
Pipe Plug; 1/8" NPT, Brass, internal Allen Socket head, (each); carb adapter plate, rear 3
Pipe Plug; 3/8" NPT, Steel, Cadmium-plated, Allen Socket head, (Each); cyl head 2
Pipe Plug; 1/2" NPT, steel, Zinc, Allen Socket head, (each) intake manifold, rear; water pump 4
Valve Cover; SBC Tall, Aluminum, Polished, Ball-Milled Flame Logo, One Hole each, Baffles + Grommets incld.
1/4-20 x 1 SOCKET HEAD CAP SCREW ALLOY PLN
GMPP Valve Cover Breather; Push-In, Filtered, Chrome Top w/ Bow-Tie Logo, Fits 1.22" hole
Valve cover gaskets; SBC cork-laminate w/ steel shim, 1/4" thick (pair)