Índice para Summer 2016 em Engine Masters

While the dyno can help a builder refine a given package, it can be a critical tool in component selection. When it comes to making the most of any engine build, there is little that can substitute for empirical testing—that is, running the numbers in search of the optimal combination. Not so long ago, real test data was relatively thin, with only a select few shops being equipped with dyno test equipment. Decades ago, dynos were bare-bones devices, with little in the way of data— often just a torque gauge with no means of recording information. Manual load controls were common, where operator skill played a major role in repeatable and accurate data. We’ve come a long way since then, with computerized dynos capable of recording many channels of data,…

The Cleveland Ford has an interesting history. Debuting in 1970 at 351 ci, it was right in the middle of average as far as displacement for the era, but topping those cubes was a cylinder-head design that was anything but ordinary. The Ford 335-Series “Cleveland” small-block heads were revolutionary as much as evolutionary, featuring design cues that still form the basis for all-out unlimited race heads today. Rather than the common inline valve arrangement, the valves were canted toward the cylinder centerline in a compact combustion chamber. The runners were arranged in a symmetrical port layout, the preferred arrangement for all-out aftermarket racing heads—and, yes, the GM LSseries engines. The valves were huge, even by big-block standards, measuring 2.19 intake and 1.71 exhaust. Along with the enormous valves, the heads…

In the 1860’s Charles T. Porter and John F. Allen realized they could increase the efficiency of their steam engine if they increased the rpm. To make the engine live, they applied the first “scientific balance” to reduce the effects of the rotating inertia and steam forces on the bearings. From that beginning, we are still attempting to understand the dynamics of balancing a reciprocating engine. For decades, machinists and engine builders have been taught that when balancing a crankshaft, its counterweights should equal 100 percent of the rotating mass and 50 percent of the reciprocating mass. Machinists have used this formula to calculate bobweight for decades. While this technique works extremely well for the vast majority of street and race 90-degree V-8 engines, the truth of the matter is…

What makes up an effective lubrication system? For pure racing applications, the dry sump wins. This system ensures a constant supply of oil from a remote tank, which also serves to eliminate aeration. Inside the engine, the scavenging system removes the excess, keeping control of any loose oil. While there are many advantages to a dry sump, these systems also mean a lot of extra plumbing, an external pump, and the tank. For most of us, the dry sump and its cost and complexity is an impractical solution for all but very specific race applications. This leaves us with the common factory-style wet sump, or some variation of it. There really are just two things you want from the lubrication system: a constant supply of pressurized oil to the engine,…

WEIAND — OIL PAN KITS Weiand’s fabricated oil pan kits feature an allaluminum construction to keep excess weight off of the nose of your car, whether you’re running down the 1,320, shaving seconds at a local autocross, or just showing up at the local cruise-in. They also feature trap-door baffIes to keep oil under control during hard acceleration, turning, and braking. When combined with the increased oil capacity, Weiand’s oil pans ensure that high-performance engine oiling systems are properly fed to help reduce any possible oil-starvation issues. The gold iridite or black finishes will help make your car look as good from underneath as it does up top, whether it is a drag car, road-racing car, circle-track car, or any other hot rod equipped with a small-block Chevy, small-block Ford,…

When it comes to sheer numbers over a long production run, the 383 was the most common big-block produced by Chrysler. Back in the famed era of production muscle cars, the 383 served duty in performance applications as the standard engine in midrange performance cars, such as the famous Road Runner and Super Bee models. These 383 cars were far more plentiful than their more famous 440 and Hemi brethren, offering a taste of performance to the masses. With a factory rating of 335 SAE gross horsepower, the 383 was not quite up to the level of the upper-tier muscle engines, but with the same cam, exhaust manifolds, and heads as the 440, the 383 seemed to pull deeper into the rpm range, making it more than a match for…

“Part of our evaluation was a real drive-time evaluation, with a 1977 Dodge D100 Utiline ‘Muscle Truck’ as the testbed.” When it comes to carburetors, we find that most guys will fall into one of two camps. There are the hardcore racers/tuners, for whom the bigger it is—and the more parts and pieces can be swapped around and fiddled with—the better. Then there are the guys who just want one feature: a carb that will bolt onto the engine and work with a minimum of fuss—and get the job done. Of course, there are crossovers in these categories of users, and in carburetors too. We have met plenty of guys who will buy Holley HP series race carbs, with replaceable jets and orifices at every conceivable tuning point, bolt them…

On the stand for a full rework, we had a 502 Chevy Ramjet engine, a popular but mild-mannered crate engine offered by General Motors. A 502 Chevrolet is not your standard production big-block, and its most distinguishing characteristic is the oversized 4.470-inch bore. Production big-blocks were a full 0.220-inch smaller in terms of bore size, and that big bore definitely provides an edge. A big bore provides a substantial displacement without the necessity of ungainly stroke increases. The formula here equals big cubes at moderate pistons speeds, with less bore shrouding of the airflow into the engine. A big bore produces lower reciprocating loads at high rpm than a similarly sized combination based upon a production block with its smaller bore. This block represents a great opportunity to unleash tremendous…