In 1980, I built a 400-ft-lb, 404-hp 350 replacement for the anemic 158- hp 305 in my California Pontiac Trans Am. Back then, it took real effort to exceed 400 ft-lbs and similar horsepower. Imagine my disappointment when, no matter what I used for mufflers, the output dropped by some 20 ft-lbs and 25 hp. […]

British engineer and author Philip H. Smith wrote a 250-page book entirely on intake and exhaust systems because the subject warranted it. We don’t have space here to do that, so you are going to get the hands-on basics of an important and complex subject.   This tech tip is from the full book, DAVID […]

The block is, in effect, the case that has to contain all the loads brought on by the development of the power we are seeking to build. If you are building an engine for any serious competition, the first move should be to sonic-check a selection of blocks. This allows you to throw out any […]

By now, I am sure you have a good idea of both the complexity and importance of the valvetrain, as this is the third consecutive chapter dealing with it. What I intend to focus on here is the practical application of what I have so far explained.   This tech tip is from the full […]

We are going into more detail on valve-event timing and how the spec of the rest of the engine affects optimal events.   This tech tip is from the full book, DAVID VIZARD’S HOW TO BUILD HORSEPOWER. For a comprehensive guide on this entire subject you can visit this link: LEARN MORE ABOUT THIS BOOK […]

Selecting a cam or, more accurately, deciding the cam events that the engine needs has traditionally been regarded as a black art. Most publications feed you just enough info for you to get into trouble (in most instances) or for you to decide you should let a tech guy at a cam company make the […]

The greater our success in terms of porting and increasing compression ratio and engine RPM, the harder it becomes to effectivly lightoff the compressed charge. Fortunately, improving the ignition is not a great challenge these days and, for the most part, not that costly either. But the situation has not always been so. Until the […]

As I have established, high-airflow potential, especially through the cylinder head, is a key element in producing power. If you are starting with as-cast parts, a means of reshaping them and testing the subsequent flow results are very useful aids to maximizing output. In short, the subjects in this chapter are physically porting heads, intakes, […]

We have finally arrived at the so-called cork in the system, as far as power production is concerned. As Chart 6-1 shows, optimizing airflow (and that means getting as much as possible) is the number-one goal. But as far as heads are concerned, it is not the only factor in making big power numbers. To […]

Let’s focus on the word “supercharge” for a moment. In the context of this book, it means to fill the cylinder above and beyond the displacement that it ordinarily has. For instance, if a cylinder has a 50-ci displacement and, by one means or another we cram 75 ci into it, then we can say […]