EMS

Converting to an Engine Management System

No one disputes that Engine Management Systems are far more expensive than carbs and points. So why haven’t engine and car manufacturers stuck with the cheaper alternative? Production line costs would be heaps less, wouldn’t they? The answer is that manufacturers had been under increasing pressure since the late seventies to clean up the air. More efficient ways of burning fuel and air had to be found, so that deadly pollutants would no longer sour the air we breathe. The gradual introduction of power robbing anti-pollution devices, de-tuning and the lowering of compression ratios had all hot rodders crying foul. Pre-pollution engines were, and still are, the preferred means of powering the average performance oriented vehicle, although the high performance four cylinder and rotary engines of today are giving traditional hot rodders a run for their money. With all due respect to enthusiasts of small engines that pack a punch, the main ingredient in four cylinder hot rodding is power to weight ratios. This book is for lovers of brute strength, so we’ll stick to more conventional, V8 type engines in this book.

During the mid eighties, computer based Engine Management Systems (EMS) became a production line reality. Since then, no vehicle has been manufactured with points and carbs, but enthusiasts are still using them because of their simplicity. These same enthusiasts recognise that there must be something in this high tech stuff for them, after all, their favourite engine manufacturers (GM, Ford, Chrysler) were using EMS exclusively and, judging by the way these late model cars were leaving them at the lights, they are absolutely right. Before we get into the actual conversion from carbs to computers, let’s take a look at how Engine Management Systems work, with a view to using the technology on our hot rod project.