No one is born knowing how to file down rings or torque down main caps, so there’s nothing wrong with being an engine-building virgin. Who cares if your more experienced gearhead buddies might bust your chops about it? We all have to start somewhere, and with enough research and practice, you’ll be able to smoke those fools with a kickin’ engine combination that you built with your own two hands. Perhaps the greatest attribute of Chevy small- and big-blocks isn’t so much their prolific horsepower potential, but rather how easy and affordable they are for anyone to build right in your own garage. As hot rodders, the urge to plan and execute your first engine build is only natural; however, knowledge is the best defense against making costly mistakes. Fortunately, help is only a couple of paragraphs away.
In reality, explaining how to build an engine one step at a time is beyond the scope of any single magazine story. Instead, we’ll walk you through the logistics process that every engine build must go through before a single wrench is turned. The first step involves establishing a budget, then determining horsepower and streetability targets. From there, it’s a matter of deciding upon a cubic-inch tally that best suits your needs, then selecting a block, rotating assembly, camshaft, valvetrain, and cylinder heads to make it all happen. Then comes the fun part: turning a pile of parts into a running engine. As anyone who has ever built a motor will attest, there’s nothing like cracking the throttle on an engine you built yourself for the very first time.
Whether they’re from GMPP...
Whether they’re from GMPP or Dart, Smeding uses brand-new blocks exclusively in all its crate engine packages. Although used cores can serve as great foundations for performance motors, using new blocks eliminates the potential for excessive cylinder bore and main cap wear, rust in the water jackets, and stripped boltholes.
Instead of masquerading as engine builders, we acknowledged our status as scribes, and tapped into the expertise of Smeding Performance. The company has been building turnkey crate motors for over 20 years, and boasts an impressive product line ranging from 360hp small-blocks to 900hp-blown big-blocks. Smeding Performance builds more engines in one week than most hot rodders build in their life, and as such, it has a wealth of insight and expert tips in its data bank to share with enthusiasts.
Race motors are interesting specimens of engineering that boast insane horsepower. The only thing more insane is how much they cost to build, and the amount of maintenance they require. Sure, it’s easy to be wowed by the 11,000-plus rpm that NHRA Pro Stock engines turn while producing nearly 3 hp per cubic inch. However, the only reason teams must abuse their motors so thoroughly by turning so many rpm is due to rules and restrictions that limit maximum displacement. The good news for street cars is that there is no sanctioning body that limits the number of cubic inches you can pack into your street machine. Since larger motors produce more torque, and horsepower is nothing more than torque multiplied by rpm, they can make the same horsepower as smaller displacement motors without having to turn as many rpm. The net effect of keeping the rpm down is vastly improved valvetrain reliability, smoother idle quality, and the ability to run taller gearing for more relaxed freeway cruising and increases in fuel mileage. Likewise, turning fewer rpm means that you can get by with a less aggressive camshaft, which substantially improves driveability in addition to fattening up low and midrange torque. Consequently, if you use the largest cubic-inch short-block that you can afford as the foundation for your engine build, it’s hard to go wrong. “Our goal is to design a motor to be as efficient as possible for the rpm range we want to run it in, then to use the best cylinder heads available,” Ben Smeding explains. “That way, you don’t need to run a big cam, which makes an engine combination much more streetable.”
The last thing you want to...
The last thing you want to do is install a high-dollar rotating assembly and valvetrain into a block with poor machine work. Even if you’re on a limited budget, machine work is one area where it doesn’t pay to skimp. Smeding installs torque plates on top of the block during the honing process to simulate the clamping loads of the cylinder heads. After machining is complete, the block is hot-tanked.
Here’s just one example of...
Here’s just one example of where an experienced engine shop is priceless. The Fed’s push to reduce vehicle emissions has resulted in motor oils in which critical lubrication-enhancing additives have been eliminated. Smeding noticed excessive valvetrain wear on its flat-tappet cam motors, and came up with a simple yet ingenious solution. By notching a 0.012-inch groove into the bottom side of each lifter bore, Smeding is able to dramatically improve oil flow and reduce lifter wear.
Replacing the cam bearings...
Replacing the cam bearings is standard procedure in any engine build. The process involves tapping the bearings into the cam tunnel with a special installation tool and a hammer. Care must be taken to ensure that the oiling holes in the cam tunnel align perfectly with the holes in the bearings. This is particularly important on production blocks that lubricate the cam bearings before the crank and rods. Most machine shops will charge about $30 to install new bearings.