Big-Block Bottom End: 632 Cubes Of EngineLabs Giveaway Short-Block

By now, you’ve likely heard about the EngineLabs Giveaway presented by Summit Racing, where we have assembled a killer 632 cubic-inch big-block Chevrolet engine on the PRI Show floor using some of the latest and greatest parts in the industry. This engine should easily eclipse the 1,000 horsepower mark on the dyno, and the best part about it, is that you can win this engine by simply heading to www.enginelabsgiveaway.com and entering for free.

When we say we’ve used some of the latest and greatest parts in the industry, that is no exaggeration. We have some parts that are seeing their first light of day in our project, coupled with some parts that are the gold standard for high performance engines. So, let’s dive into our 632-cube short-block and see the foundation of this pump-gas monster.

The Base of this Ace

When building a 632, the block selection is critical. To reach that amount of displacement, your block needs to not only handle a monster 4.750-inch stroke, but also a massive 4.600-inch bore. Since we plan on making some serious steam with this engine, it not only needs to be able to handle the large dimensions, but keep enough meat in the block to still handle big power. To do that, we went with a brand-new offering on the market — the JLine Performance tall-deck iron block.

As the name implies, Pro Stock legend Jason Line has started making his own big-block Chevrolet engine blocks in several different configurations. For our project, we opted for a cast-iron 10.200-inch deck-height block, with a .400-inch raised camshaft and 55mm cam bores (P/N: JL-RC102-I-460). The block comes with four-bolt main caps, machined out of billet 4140 steel, and ARP 12-point main studs designed specifically for the JLine block. The JLine design incorporates a revised oiling system as well as screw-in ORB freeze plugs.

All of the JLine Performance block parts and components are manufactured in the USA by American companies, and all the final machining and clearancing for the massive stroke was done by our engine builder Nick Bacalis at his shop, Bullet Racing Engines.

A Huge Swing

With the right home for big cubes, we turned to SCAT for an equally impressive crankshaft. Since we are aiming for a max-rowdy N/A pump-gas build for the EngineLabs Giveaway, we needed an appropriately lightweight crank for both throttle response as well as smooth high-RPM operation. Checking all those boxes is the SCAT Superlight forged 4.75-inch-stroke crank. The internally-balanced fully counterweighted beast (P/N: 4-454-4750-6700-C-3) not only shaves considerable weight off of a full-weight big-block crankshaft, it also adds considerable strength, thanks to it’s forged 4340 steel construction.

To perform even better at high RPM and reduce power-robbing windage, the counterweights have been fully profiled with SCAT’s Aero-Cut design, as well as lightening holes machined into the rod journals. Chamfered oil holes come standard to ensure lubrication is not an issue, and all the journals are nitride hardened before being finished with large radii. This is about as high-end as you can get out of a forged crankshaft. The crankshaft sits in King Engine Bearings’ XP lineup of tri-metal bearings. Featuring King’s pMaxKote polymer coating, these bearings are the pinnacle of King’s bearing lineup.

Hanging off of the crankshaft are a set of SCAT’s forged H-beam Pro Sport connecting rods (P/N: 2-454-6700-2200-L19). They are made from 4340 steel with a 6.700-inch center-to-center length, and have been profiled with big stroker applications in mind. The small end features a .990-inch bronze bushing, while the large end has a dowled cap, which is secured by 7/16-inch ARP L19 rod bolts, making these the absolute strongest connecting rod in SCAT’s lineup. Like the mains, the rods house a set of King’s XPC coated rod bearings.

Connected to those rods are a set of monster slugs, in the form of custom RaceTec forged 2618 pistons. These pistons were custom-designed for the valve layout of our Edelbrock DR-17 cylinder heads, with RaceTec’s engineers designing a 0.9mm, 0.9mm, 3.0mm ring groove setup, balancing thin rings with street-engine longevity. The pistons feature a 20cc dish along with lateral gas ports for improved ring seal.

Speaking of ring seal, the ring grooves are filled with a set of piston rings from Total Seal. In addition to the lateral gas ports of the pistons, a gas-ported stainless steel top ring is utilized, along with a Napier second ring. The 3.0mm stainless oil rings feature 14 pounds of tension, balancing oil control with efficient operation.

Controlling The Lifeblood of the EngineLabs Giveaway Big-Block

For such a large engine, controlling the oil can be a challenge. It’s not just the volume of oil, but the length of the crank stroke and RPM that also make oil control in the EngineLabs Giveaway 632 a challenge. Thankfully, Melling makes a line of billet aluminum, high-volume, high-pressure oil pumps known as the Select pumps (P/N: 10070-800S). Featuring an integrated pickup into the pump housing, the spur-gear pump is designed for an eight-inch-deep sump. However, since we have a raised camshaft, we needed a longer-than-normal oil pump driveshaft, and that came in the form of Moroso’s shaft, designed specifically for .400-inch-raised-cam applications.

Housing the Melling Select pump is a Moroso aluminum drag race oil pan (P/N: 20382). The rear-sump seven-quart pan is designed with significant oil control methods built into it. A full louvered windage tray is built into the pan, with dividers sectioning off each crank throw into its own section. It’s designed with a double kick-out to handle the 4.75-inch stroke, and dual magnetic drain plugs to make maintenance as easy as possible. It also accommodates a dipstick, which we’re utilizing, because as Nick says, this is a street engine, and street engines have dipsticks.

Controlling the harmonics of the short-block is an ATI Super Damper (P/N: 917301) and timing pointer (P/N: 918958). The specific Super Damper we’re using for this engine is a lightweight aluminum shell 7.074-inch-diameter three-ring model that comes in at only 5.45 pounds. The damper is SFI 18.1 certified and comes with laser-engraved timing markings around all 360 degrees of the aluminum damper shell.

Accessories, Because It’s A Street Engine

Even though this is going to be a high-revving big-block monster, we’re still running a front accessory drive, since that’s the way it will go into the winner’s car (so yet another reason to get entered to win). For that, we turned to Holley and their complete accessory systems. In our case, we went with a mid-mount kit (P/N: 20-242BK), that is a serpentine-style kit, incorporating water pump, air conditioning, power steering and an LT1-style alternator.

Speaking of the alternator, for that, we turned to Powermaster and one of its HPR small-frame alternators. Rated at 180 amps at full boogie, the compact unit cranks out over 145 amps at idle, which should be more than enough to run all the electronics anyone might be running with an engine like this.

All of these parts combined make for an incredible bottom-end of the EngineLabs Giveaway presented by Summit Racing. Stay tuned as we dive into the top end next. If you thought these were cool parts, just you wait… there are even more killer components being used. And remember, there is still plenty of time to get entered for your chance to win this incredible engine at www.enginelabsgiveaway.com. It’s completely free, so what are you waiting for?