You've finally decided to see what all the fuss is about, and you want to build an engine. It's like a gearhead rite of passage. If you're into horsepower like we are, then a torque wrench in your hands is probably more comfortable than a knife and fork.
The goal this month is to show you the details behind building a small-block Chevy. Entire books have been written on the subject, so we've had to streamline the effort a bit, but to fill in the gaps, we've included a sidebar listing all the pertinent stories covering ideas like setting bearing clearance, reading a micrometer, computing compression ratio, how to degree a cam, and even torque specs so you don't have to go searching for the information. Many of these stories are already on our Web site. You can log on, download the stories, and create your own personal How to Build a Small-Block notebook.
The other major goal of this story is to show you how to build this engine correctly. That means that the idea of measuring one rod with Plastigage and assuming the rest are OK is about as ridiculous as Saddam hangin' with the Pope. The message here is that even a stock replacement engine should be assembled right the first time. Measure all the clearances and do your homework, even if it means trial-assembling the engine several times. That way there will be no surprises. Try a shortcut, and you may end up with a very expensive pile of junk.
We will be assembling a typical 375hp 355ci small-block using some very affordable parts. We will give you a complete rundown of every part, part number, and price for this entire operation. The bottom-line price is a bit steep compared to other stories you may have read, but that's because we've included everything. That includes the oil filter, spark plugs, pulleys, and virtually every nut and bolt. The more parts you already have, the less expensive this whole operation will be to duplicate.
In researching this engine, we priced out the difference between grinding a used crank and opting for a new Scat cast crank and 4340 steel rods. Surprisingly, the extra cost of the new crank is minimal and you end up with much stronger connecting rods. To keep the price down, we selected a set of Federal-Mogul's coated hypereutectic dished pistons intended to work with the 64cc-chamber Vortec iron heads. Since this was supposed to be a daily-driver-style engine, we also decided to keep the cam timing reasonable and selected a Comp Cams Xtreme Energy 262 cam that should produce excellent torque and horsepower. The Performer RPM intake will help this little motor make some decent power with the help of an Edelbrock Performer 750-cfm carb and a set of long-tube Hedman 15/8-inch headers. While we ran out of time to dyno-test this engine, it should easily punch out around 375 hp with at least 12 to 14 inches of manifold vacuum. The idea here is to show you exactly what's involved with building a complete carbureted small-block Chevy that's ready to drop in between the fenderwells of your Camaro, Chevelle, Nova, or pickup. It's fun watching the process come together. Once everything is clean and measured, it slowly assembles right before your eyes. The best part is when your baby fires for the first time. When that engine finally lights off and makes noise, it's a fantastic feeling of accomplishment. The only thing better is when you're able to stomp on the throttle and experience the power of what you put together. Build one engine--and build it right--and you'll want to build another just for the pleasure of doing it again.
Enough of the motivational speech. Let's get after this small-block and see what it takes to put one together.