1968 Chevrolet Chevelle - The Howitzer - Project Car - Popular Hot Rodding
496 Cubes Of Big-Block Artillery For Our '68 Chevelle Project
From the October, 2007 issue of Popular Hot Rodding
By Steve Dulcich
Photography by Johnny Hunkins
In terms of heavy ordinance, a Howitzer is a big gun designed to do damage by propelling a large projectile with a seriously unruly velocity. The aim of our big-block Chevrolet build is to achieve a very similar goal, but with Hunkins' '68 Chevelle playing the part of the projectile. Moving a big street machine in heavy-hitting fashion is best done with a heavy-hitting powerplant. You can read that as big on cubes, big on torque, and, of course, big on power. Those three characteristics pretty much define the objectives of our Howitzer 496 stroker. Our goal was to build the engine using quality parts on a realistic working man's budget, which may be a little more than what an odd-jobber or alley-dwelling wino can spend, but a lot less than many cost-no-object builds we've seen.
The 496 big-block Chevy stroker has become a popular combination, based on a 454 block bored .060 inch, and fitted with an aftermarket crankshaft with an increase in stroke to 4.250 inch from the factory 4.00 inch. Frankly, when the engine is receiving a full rebuild, that quarter-inch of stroke comes mighty cheap. Our Scat rotating assembly retails at $1,268 when sourced from Survival Motorsports, and includes a cast-steel crank, I-beam rods, SRP domed pistons, JE rings, and Clevite bearings. Not a bad deal for most of the bottom-end hard parts, and a real bargain considering the extra 36 cubes bagged in the deal. When considering to build a fresh 454 with new rods and pistons, the ante is just not that much more to step up to a full 496 rotating assembly and let those extra cubes work.
"I have a hard time sleeping...
"I have a hard time sleeping at night, thinking about this 496 in the Chevelle. This thing is going to scare the neighborhood kids silly."-Johnny Hunkins
Although it isn't a forging,...
Although it isn't a forging, the Scat cast-steel crank is substantially stronger than a production cast crank, and has been proven in performance street and race applications. Notice the filet radius at the journals, net-shape counterweights, and nicely detailed oil holes. The Scat assembly is close enough in balance to assemble at home as-is, but we had the guys at B&T Performance (Pomona, CA) balance ours to our specific flexplate and balancer.
Viewed side by side, it's...
Viewed side by side, it's easy to see the extra beef in the new Scat I-beam rod, compared to a stock rod (left). Harder to see is the advantage in materials, with the Scat rod's 4130 steel having significantly more strength than the 10-series OEM carbon steel.
Of course, more cubes naturally have a heartier appetite for air, so taking advantage of the displacement increase means a healthy set of cylinder heads. We knew that we wanted a set of aftermarket aluminum heads. Though there are some good iron heads on the market, the weight advantage of aluminum is a definite plus when considering the conspicuous heft of an all-iron big-block. Before jumping off the deep end, it pays to have a set objective in mind when shopping the virtually unlimited range of big-block Chevy cylinder heads. Our notion was to build a torquey pump-gas street piece, not an all-out drag engine. We would select a hydraulic roller cam for long-term durability and low maintenance. The cam selection, along with the moderate street bottom end, dictates a maximum reliable engine speed between 6,000 and 6,500 rpm-not 7,000-plus rpm. For this max rpm range, a moderate performance cylinder head would serve the engine's needs handily. We went with the Racing Head Service 320cc (intake runner) heads. At just over $1,800 (per pair, assembled), these heads are reasonably priced, and with over 350 cfm of max airflow on hand, we had more than enough air to make power in our street combination.
A stroker with nearly 500 ci will naturally produce torque in abundance, and torque would be key to effortlessly heaving the Street Sweeper Chevelle. We decided not to fight the natural tendency for torque, but instead sought to maximize it in the rest of our parts selection. To complement the cylinder heads, an Edelbrock Performer RPM Air Gap intake was selected. A two-plane with 180-degree runner separation and ample runner length will always have a torque advantage in the low- to mid-range compared to a single-plane. The Air Gap is about as good as it gets in terms of out-of-the-box flow from a two-plane, and the divorced runners maintain a cooler, more powerful fuel/air charge. Ensuring adequate air with fuel mixed in the proper proportion, we coupled the manifold to an 850 cfm Mighty Demon carb. Sure, a single-plane would likely bring in a higher peak horsepower number at the top of the rpm range, and many builders will make that trade. Our plan was to go for the fatter torque curve over a wider portion of the engine's operating range, and retain the stock flat hood in the deal.
Similarly, when it came time to select the camshaft, we had a few alternatives. A hydraulic roller has just too much going for it to pass it up in this type of application, particularly in a big stroker that doesn't need extreme rpm to make power. Few will argue the reliability advantage of a hydraulic roller in comparison to a solid roller or a flat-tappet design. While either of the alternative solids can provide the benefit of easier high-rpm potential, the beauty of a stroker is that you don't have to go there to reap its performance rewards. As with the rest of the combination, we were looking for a camshaft profile that would come on with strong torque, and yet pull without argument to the 6,000 rpm range.
With a longer stroke, the...
With a longer stroke, the piston requires a shorter compression height, which is the distance from the center of the piston pin to the top of the piston. Note that the piston pin hole is machined right into the oil ring land.
Scat's Budget 496 RecipeBig...
Scat's Budget 496 RecipeBig cubes can mean big power, and one of the best ways to easily get 496 inches is a matched stroker kit. Rather than a piecemeal set of parts, Scat's Series 9000 kit (around $1,300, mail order) has everything, including a cast steel crank, I-beam rods, forged SRP pistons, JE Pro Seal moly rings, and Clevite bearings. The balance factor was accurate to within 2 grams on our internally balanced kit. Basically all the guts you need in a pre-matched package, ready to assemble.
The SRP pistons are manufactured...
The SRP pistons are manufactured by JE, and are a part of its affordable line of high-performance forged pistons. These PN 212157 pistons are made for Scat's .060-over stroker combination, with the correct compression height and skirt clearance. Ring grooves are 1/16-1/16-3/16, and the domes measure 18 cc, to give a final compression ratio of 10.2:1 when used with a 118cc combustion chamber.
A relatively narrow lobe separation is key for brutal, hard-hitting mid-range torque, while plenty of overlap and extra exhaust duration is the usual call for making an engine hang on into the higher revs. We found both of these qualities in COMP's new Thumpr line of camshafts. A COMP Big Mutha Thumpr (BMT) PN 11-602-8 stick got the nod, which is an off-the-shelf grind featuring 243/257 degrees of duration at .050 inch, .570/.554-inch lift, and a tight 107-degree lobe separation angle. To make the most of the camshaft, a reliable valvetrain was assembled with components from COMP, including COMP's retrofit hydraulic roller lifters to fit out a Mark IV block, COMP Hi-Tech 3/8-inch pushrods, and aluminum 1.7:1 roller rockers. A final trick to really make the big engine spin to its full potential was to specify COMP's Beehive valvesprings on those RHS cylinder heads. RHS obliged this request and now features this setup with a dedicated part number (11001-05).
An oil ring support rail is...
An oil ring support rail is used to retain the oil ring when the pin breaches its groove. A small dimple on the rail lies face-down in the slot created by the pin hole, keeping the rail in position.
A key part of the Howitzer's...
A key part of the Howitzer's power-producing scheme was a set of high-flowing aluminum heads. For the rpm range we intended, these RHS 320cc cylinder heads proved to be ideal.
With a hydraulic roller cam,...
With a hydraulic roller cam, maintaining high-rpm valve control can be a challenge. We ordered our heads fitted with COMP's beehive springs, which can significantly improve valvetrain control and stability. RHS now offers this combination as an option on its big-block Chevy head package.
With this, we had our basic combination, and the promise of mega torque. We took the load of parts-including oil system components from Melling, all-new tin from AAMidwest, an MSD HEI setup, and ARP bolts to screw it all together-to Andy Mitchell's Outlaw Racing Engines (Upland, CA). Andy oversaw the assembly, and measured everything to blueprint specs, while Hunkins and Outlaw part-timer Tim Martindale, helped work the nuts and bolts between shooting photographs and cooking ribeyes on the grill. What emerged was a hot-looking 496 that will fit under the stock Chevelle hood, chomping at the chance to prove its stuff come dyno day.
It wasn't long before the big-block was hauled to Westech Performance Group and bolted on a SuperFlow 902 dyno to validate the combination. Dyno master Steve Brul performed the preliminary checks of base carb and ignition settings, and the rat fired with authority. With a hydraulic roller combination, the cam break-in drama of a flat tappet is completely sidestepped, but the engine was run through a programmed load cycle to help seat the rings and prepare for the action to come. With a compression ratio of 10.2:1, there was no need to feed the Mighty Demon carb anything but standard-issue pump premium fuel. A few static checks under load helped sort the jetting.
With the formalities out of the way, it was time to let it rip. As the numbers rolled in, the big-block showed its true character. Want to propel a heavy street machine with explosive power? The Howitzer was revealing itself to be the ideal weapon, with a numbing 600 lb-ft churning right from 3,200 rpm, climbing to a peak of 635 lb-ft at 3,800 rpm. Wow, that's a lot of torque, and it comes in right now! We've seen some engines build a lot of low-end torque, only to give up low in the rpm range with no big horsepower bang up top. This isn't the case with The Howitzer. Our big Chevy just kept coming, making power right up to 6,000 rpm, and beyond. Torque recorded over 600 lb-ft right up to 5,300 rpm, and power held strong to the top, recording a peak of 626 hp, coming in at 5,900 rpm. Even past peak, the engine only slowly came off the crest, pulling easily higher. This is an engine that will hit like a cannon out of the hole, and keep pulling like an artillery piece barreling headlong to a shift point just over 6,000 rpm. Our Howitzer is one engine that's earned its name.
We brought the RHS heads to...
We brought the RHS heads to Westech Performance Group where they were tested on a SuperFlow 600 bench to evaluate flow. The 320cc intake port delivered an impressive 328/350-cfm peak flow on the intake ports, and 276 cfm on the exhaust.
Big Mutha Thumpr:When COMP's...
Big Mutha Thumpr:When COMP's new Thumpr hydraulic roller cams first came out, many thought it was just a noise cam, but we knew otherwise. With a long exhaust duration and a narrow 107-degree LSA, we saw a recipe for big street power. Retrofit hydraulic lifters are needed for engines not originally equipped with a hydraulic roller cam, so we also ordered the retrofit lifter kit for our BBC. Thumpr cams are available for small- and big-block Chevy, Ford Windsor, and small-block Chrysler. Three unique grinds are available in each engine family-we chose the biggest for our Rat Chevy (299/319 advertised duration, 243/257 at .050, .570/.554-inch lift, 107 LSA).
File-fitting the rings allows...
File-fitting the rings allows a builder to control the end gaps for minimal compression leakage. Outlaw uses go/no-go feeler gauges to quickly and accurately determine the end gap. We were shooting for a .020-inch gap for the top compression ring, .022 inch for the second, and anywhere between .016 and .028 inch on the oil rings.
The bores were prepped by...
The bores were prepped by Outlaw Racing Engines (Upland, CA), with final honing shown here. With any build, internal clearances are critical. Andy Mitchell and the crew at Outlaw cut no corners in assuring our engine was dead-on.
Additional measurements at...
Additional measurements at the bottom end include the crank endplay, main and rod bearing clearances, and rod side clearance. We quickly discovered that Outlaw Racing checks all clearances meticulously.
Make sure the rods and pistons...
Make sure the rods and pistons are assembled properly, and the ring gaps are staggered to specs. On start-up, Outlaw likes the top ring gap at the intake valve, where the chamber runs coolest. The second ring gap should be placed opposite of the top ring. The pistons should slide into the bores smoothly without hanging-up on a ring. An extra set of hands can help guide the rod to the journals.
With Hunkins helping to man...
With Hunkins helping to man the wrenches, the bottom end of the engine went together with no unforeseen problems. This is where thorough preparation and quality components pay off. We liked the digital Snap-on torque wrench, which alerts the user with audible and vibration cues.
All the work proved to be...
All the work proved to be worth it on dyno day, with 635 lb-ft of torque and 626 hp. Hunkins had to cough up a $20 wager when Mitchell's power prediction proved to be virtually dead-on, exceeding the numbers Hunkins had expected.
We found some interesting tidbits when we dug into testing the flow of our new RHS cylinder heads. Only a few issues back (see "The Ironman," July 2007), we used a set of Summit iron cylinder heads, and were more than impressed with the numbers recorded when the machine shop sent them out for testing. What surprised us was that testing the RHS cylinder heads at Westech on its FlowCom-equipped SuperFlow bench showed nearly the same flow. However, we've preached the importance of not taking numbers from two different benches when making comparisons, and were curious enough to re-test the iron heads on the same bench to get a valid comparison. It seems the Westech flowbench is definitely less generous than the bench used to originally test the Summit heads. Testing back-to-back on the same bench gave us a valid set of numbers for the comparison.
|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 |
Have a steady hand when checking...
Have a steady hand when checking the P/V clearance
Checking P/V Clearance
One check that should not be neglected is the piston-to-valve clearance. Coming up short here can be disastrous, though our assembly was well within Outlaw's safe specifications. The proper procedure is to place a few dabs of clay on the piston valve reliefs, then coat them lightly with oil. Install the cylinder head temporarily on the block, install the valvetrain on that cylinder (using light "checker" springs), then rotate the engine over by hand. The valves will leave witness marks in the clay, which can then be carefully bisected, and the clearance measured. The p/v clearance measured .178 inch with the Thumpr cam, which is more than enough. You should look for a bare minimum of .100 inch, with .120 being preferable as a minimum.
|SUMMIT/DART IRON HEADS |
|VALVE ||INTAKE ||INTAKE ||EXHAUST |
|LIFT ||cfm(poor) ||cfm(good) ||cfm |
|.050 ||35.5 ||32.4 ||31.5 |
|.100 ||72 ||69 ||66 |
|.200 ||144 ||143 ||103 |
|.300 ||196 ||197 ||152 |
|.400 ||247 ||249 ||188 |
|.500 ||286 ||292 ||217 |
|.600 ||307 ||320 ||240 |
|.700 ||307 ||326 ||256 |
The Howitzer Vs. The Ironman
What's The Diff?Sharp eyes will notice there's a lot of commonality between The Howitzer and The Ironman, a 468-inch big-block we put together in the July issue. Both engines are one and the same. Sort of. When we put the iron-headed 468 on the dyno and made 579 hp, we decided to go back for a little more power and a little less weight before dropping it into the Chevelle. The primary differences: Swapping the iron Summit 308cc heads for the RHS 320cc aluminum heads, boosting the displacement from 468 inches (basically a stock .060-over 454) to 496 inches using a longer 4.25-inch stroke, and-surprise-stepping back from the brink in the cam department, forsaking a radical-for-the-street .647-inch lift solid roller cam for a street-friendly .570-lift hydraulic roller (COMP's new Big Mutha Thumpr). Another smaller change was a slight increase in carb size from an annular booster 825 Mighty Demon to a downleg booster 850.
The Ironman 468 made 579 hp at 6,200 rpm and 545 lb-ft of twist at 4,200 rpm, and had a build-it-yourself price of $6,633.09. We were initially concerned that the stroked 496 might blow the budget with a more expensive set of aluminum heads, but the calculator only registers another $890.28 over the Ironman's price, and produced 47 more hp and another 90 lb-ft of torque (coming in 400 rpm earlier). We like that trade-especially with the weight savings-and we're glad we made it. Andy Mitchell of Outlaw Racing says he can build The Howitzer for you just like this for about $1,500 over the do-it-yourself price we're listing, and interested parties should call him at 909-931-4612.
|THE HOWITZER-PARTS LIST |
|Part: ||Source: ||Part No. ||Price: |
|454 Mark IV core: ||AAMidwest ||block ||$400 |
|RHS 320cc aluminum heads: ||Racing Head Service ||11001-05 ||$905.99 ea. |
|Scat 496 rotating assembly: ||Scat ||1-91610BI ||$1,268.49 |
|Scat 4.25-inch stroker cast crank: ||Scat ||945425 ||incl. |
|Scat 6.385-inch I-beam rods: ||Scat ||26385716 ||incl. |
|SRP 18cc dome forged pistons: ||JE/SRP ||212157 ||incl. |
|JE file-fit ring set: ||JE/SRP ||J100F8-4310-5 ||incl. |
|Main bearings: ||Clevite ||CLE-MS829P ||incl. |
|Rod bearings: ||Clevite ||CLE-CB734P ||incl. |
|Cam bearings: ||Summit/Clevite ||CLE-SH616S ||$19.95 |
|Edelbrock Performer RPM intake: ||Summit/Edelbrock ||EDL-7562 ||$235.88 |
|Valve cover breathers (incl. grommet): ||Summit/Edelbrock ||EDL-4405 (2) ||$13.76 |
|Intake bolt kit: ||Summit/ARP ||ARP-135-2001 ||$24.95 |
|Carb: ||850 cfm Mighty Demon/Jegs ||132-5563010GC ||$549.99 |
|Carburetor stud kit: ||Summit ||SUM-G1421 ||$3.69 |
|Thumpr BMT hydraulic roller cam: ||Summit/COMP ||CCA-11-602-8 ||$295.95 |
|Balancer bolt kit: ||Summit/COMP ||SUM-G1678 ||$7.95 |
|Hydraulic roller lifters: ||Summit/COMP ||CCA-854-16 ||$449.95 |
|Rocker arms: ||Summit/COMP, 1.7:1 ||CCA-1021-16 ||$334.39 |
|Pushrods (intake): ||Summit/COMP, 3/8 inch x 7.750 ||CCA-8905 (need 8) ||$15.69 ea. |
|Pushrods (exhaust): ||Summit/COMP, 3/8 inch x 8.800 ||CCA-7908 (need 8) ||$15.39 ea. |
|Valve covers: ||Summit/COMP ||CCA-230 ||$133.95 |
|Cam button: ||Summit/COMP ||CCA-205 ||$8.39 |
|Distributor gear: ||Summit/COMP ||CCA-12200 ||$105.95 |
|Distributor: ||Summit/MSD Street Fire HEI ||MSD-8362 ||$159.99 |
|Wires: ||Summit/MSD 8.5 Super Conductor ||MSD-31299 ||$75.95 |
|Water pump: ||PRW ||late Mark IV (long) ||$94.50 |
|Plugs: ||ACCEL ||762 ($2.25 ea) ||$18.00 |
|Intake gaskets: ||Summit/Mr. Gasket ||MRG-121 ||$10.95 |
|Exhaust gasket: ||Summit/Fel-Pro ||FPP-1412 ||$16.95 |
|Gasket set: ||Summit/Fel-Pro ||FEL-KS2618 ||$58.95 |
|Water neck: ||Summit ||SUM-G3801 ||$7.95 |
|Timing set: ||Summit ||SUM-G6610 ||$37.95 |
|Expansion plug kit: ||Summit/Sealed Power ||SLP-381-8009 ||$14.99 |
|Oil pump: ||Summit/Melling ||MEL-M77HV ||$32.95 |
|Oil pump driveshaft: ||Summit/Melling ||MEL-IS77 ||$6.63 |
|Oil pump pick-up: ||Summit/Melling ||MEL-77S2 ||$8.14 |
|Oil pump stud: ||Summit/ARP ||ARP-230-7003 ||$4.88 |
|Head bolts: ||Summit/ARP ||ARP-235-3703 ||$161.95 |
|Cam bolt kit: ||Summit/ARP ||ARP-134-1001 ||$3.88 |
|Bolt kit: ||Summit/ARP ||ARP-535-9801 ||$79.95 |
|Oil filter adapter: ||AAMidwest ||OFA305 ||$9.50 |
|Timing cover: ||AAMidwest ||TC454C ||$14.02 |
|Oil pan: ||AAMidwest ||OP454 ||$60.44 |
|Engine paint: ||Dupli-Color ||DE 1607 ||$5.99 |
|Parts total: ||$6,798.37 |
A ring filing machine, such...
A ring filing machine, such as this unit from Childs & Albert, makes the ring fitting less time consuming and more accurate. Setting the machine for the ring's bore size ensures a square end gap.
To get the rods to Outlaw's...
To get the rods to Outlaw's exact specifications, the big ends were honed slightly on a Sunnen rod machine.
Mock-up assembly of the major...
Mock-up assembly of the major components is a key to successful blueprinting. Here, the piston deck height is checked and recorded at an acceptable 0.001 inch "in the hole."
For final assembly, the parts...
For final assembly, the parts should be cleaned, and laid out in order. Care must be taken to assure they are assembled in the proper orientation. The chamber of the con rod always faces the cheek of the crankshaft, and the valve reliefs must match their corresponding locations in the head.
One of the most time-consuming...
One of the most time-consuming portions of a big-block Chevy build is ensuring the valvetrain is working properly, with the required geometry. You'll want to check the sweep of the rocker on the valve tip throughout the lift cycle, and adjust the pushrod length so that the sweep falls in the center of the valve tip. An adjustable pushrod checker is the preferred tool. Our hydraulic roller is somewhat unusual for a big-block, and required shorter-than-normal pushrods, which are considered custom (7.750-/8.800-inch long). Here, Andy holds a white card behind the rocker tip to better observe the sweep.
COMP's retrofit hydraulic...
COMP's retrofit hydraulic lifters (PN 854-16) fit where flat tappets resided before. The key is a link bar arrangement, similar to that of a solid roller race cam. Later engines originally equipped with a roller can use the OEM-style lifers, yokes, and retaining spider. Make sure you coat the lifters with a thorough film of oil before dropping them into the lifter bores.
"It makes 626 hp on pump gas while fitting under a flat hood. That's shock value." - Johnny Hunkins
|Machine Work (Outlaw Racing): |
|Clean block: || || ||$80 |
|Block bore & hone: || || ||$245 |
|Hone rods: || || ||$40 |
|Cam bearings: || || ||$60 |
|Deck resurface: || || ||$120 |
|Balancing: || || ||$180 |
|Machine shop labor total: || || ||$725 |
|Parts and Labor Total: || || ||$7,523.37 |
|SUPERFLOW DYNO RESULTS |
HOWITZER 496 BIG-BLOCK CHEVY 2.250-INCH DYNO HEADERS
|RPM ||TQ ||HP ||RPM ||TQ ||HP |
|3,100 ||597 || 353 ||4,700 ||618 ||553 |
|3,200 ||600 ||365 ||4,800 ||616 ||563 |
|3,300 ||607 ||382 ||4,900 ||613 ||572 |
|3,400 ||616 ||399 ||5,000 ||611 ||582 |
|3,500 ||624 ||416 ||5,100 ||609 ||591 |
|3,600 ||630 ||432 ||5,200 ||605 ||599 |
|3,700 ||633 ||446 ||5,300 ||600 ||606 |
|3,800 ||635 ||460 ||5,400 ||594 ||611 |
|3,900 || 635 ||472 ||5,500 ||587 ||615 |
|4,000 ||633 ||482 ||5,600 ||581 ||619 |
|4,100 ||630 ||492 ||5,700 ||574 ||623 |
|4,200 ||627 ||501 ||5,800 ||566 || 625 |
|4,300 ||624 ||511 ||5,900 ||557 || 626 |
|4,400 ||623 ||522 ||6,000 ||547 ||625 |
|4,500 ||622 ||533 ||6,100 ||537 ||624 |
|4,600 ||620 ||543 || || || |
37 degrees ignition timing82/90 jets
Andy Mitchell took great care...
Andy Mitchell took great care to ensure that the COMP Thumpr camshaft was degreed to specifications at 102 degrees intake centerline. The camshaft thrust was carefully measured and set with a thrust button prior and some slight dimpling of the timing cover.
With the cylinder heads finding...
With the cylinder heads finding their home up top, the build really progresses. Here, Tim Martindale installs the heads with ARP fasteners, and torques with the recommended ARP thread lube.
If a big engine likes to make...
If a big engine likes to make torque, a two-plane intake helps it make even more. Edelbrock's Performer RPM Air Gap works really well on a street big-block, with great torque and airflow to work into the 6,000 rpm range.
What's next? Wonder what 600-plus...
What's next? Wonder what 600-plus lb-ft of torque virtually anywhere on the power curve will do? We've gotta see what will happen when we plug this 626hp weapon into the Street Sweeper '68 Chevelle. We're gearing up to install this puppy soon.
ARP (Automotive Racing Products)800-826-3045www.arp-bolts.com
Outlaw Racing Engines909-931-4612www.outlawracingengines.com
PRW (Performance Racing Warehouse)888-377-9779www.performanceracingwarehouse.com
Racing Head Service (RHS)877-776-4323www.racingheadservice.com
"If you ever plan to build a serious big-block, I strongly recommend the chevelles.com message board. Those guys are really on their game." - Johnny Hunkins