A few years ago, Sport Truck introduced a grandiose project, called "the small-block from hell." Remember that deal? Well we've taken It 10 steps further with a big block Chevy. We wanted a lightweight engine that would eclipse the 1,000 hp mark without a supercharger, nitrous, or a blower, and we wanted to be able to roll right up to a gas pump and top off the tank. That's right. We wanted to have our cake and eat it, too.
The engine, an all-aluminum 572ci powerplant, was built by DNE Motorsports Development's owner, Dave Ebbert. The combination of parts is the result of what we had on hand and what Dave wanted to use to achieve our goal of building a lightweight and streetable 1,000hp engine. This engine is one of many Dave has put together to eclipse that power level on sub-par, 91 octane pump gasoline. It's a very tall order, but this is the real deal. The heads and camshaft are huge, the motor isn't cheap, and the compression ratio is pretty high, but it didn't knock once during any of the 30-plus dyno runs we put it through. It made 1060 hp on the dyno, which is a success in our book.
In terms of its streetability, yes, it does run on pump gas. But, it also likes to run cool, which means that if you are going to stuff a motor like this into your truck, then you'd better have one hell of a cooling system on board for the ride. We also have to mention that although it does idle happily around 1,000 rpm, it makes peak torque at 5,900 rpm and peak horsepower at 7,100 rpm. This means that the right gearing and stall converter will be important in making this engine fun to drive, especially with an Overdrive-equipped transmission.
So, there are a few detractors to building a motor like this, but the payoff is worth the effort and expense. Every gas station along the highway will have exactly what you're motor is craving. Here's a look at the parts that make up this beast and the changes Dave made to allow them all to work in harmony.
Part One: The Bottom End
The foundation of this build is a tall-deck Brodix 8B 2000 aluminum block. It's cast from A-356 virgin aluminum, and we opted for the billet steel splayed main caps, raised cam location, and enlarged cam bores for 55mm roller cam bearings. The 0.400-inch-plus raised cam bore is a must, when going with the large-diameter roller bearings in this block, in order to ensure there is enough material left in the lifter bores for oiling purposes. The block weighs just 128 pounds without the main caps in place, which is approximately 100 pounds lighter than your average OEM iron big-block.
1. The Darton ductile iron...
1. The Darton ductile iron bore sleeves can be safely machined to 4.600 inches, but we stopped at 4.5630, in order to leave enough material for several rebuilds later on. The block arrived with the sleeves untouched, although the pan rails were given clearance for a 4.750-inch stroker crankshaft. It took about three hours with a grinder to cut the bottom of the sleeves down to clear the counterweights of our 4.375-inch stroke Lunati crankshaft.
2. One peculiar point of the...
2. One peculiar point of the Brodix block is that although the mounting pad is present, it is not machined nor drilled for a mechanical fuel pump. Also, the main saddles were 0.004-inch undersized, which makes machining the aluminum block and billet steel main caps tricky. The cutter obviously would want to favor the aluminum versus the harder steel, so keeping the bore straight takes a fine touch. We turned to Paul Pfaff to machine our block, and the work was top-notch.
3. The lifter valley offers...
3. The lifter valley offers four additional head bolt bosses to aid in clamping the heads to the block. We installed a Stef's valley screen kit and magnets at the corners to keep any valvetrain debris from making its way downward. We also had Brodix machine the lifter bores for larger 0.903-inch-diameter lifters, when we ordered the block. We chose the large-diameter lifter body because it allows for a large-diameter roller and axle, which in turn means more load-carrying capability to withstand the high valvespring pressures we'll be running.
4. We used Clevite 77 A-2...
4. We used Clevite 77 A-2 bearings throughout the bottom end and had Embee Performance Coatings cover them in a dry film, anti-friction coating beforehand.
5. Lunati supplied the Pro...
5. Lunati supplied the Pro Series BB421KN forged steel crankshaft. This crank features a 4.375-inch stroke, and standard 2.750-inch main and 2.200-inch rod journals. The crank was balanced at Paul Pfaff Racing using bobweight data specified by DNE. If you look closely, you'll notice that the there are two oil pan bolt patterns drilled in the rail, and one of them has been plugged. This is because we picked up an oil pan that was originally destined for a Donovan C-500 block for a song and had to drill that pattern into our block in order for the pan to work. We got a great deal on the pan, so the extra labor was worth it.
6. The 55mm roller cam bearings...
6. The 55mm roller cam bearings are from Timkin. Unlike other blocks, Brodix provides spiral steel locks to keep the bearings from moving after installation. We test-fit the locks before deburring the block, and they were actually quite easy to install, even in the No. 2 and 3 journals, which are difficult to access.