This project is a long time in the making. I've been wanting to turbocharge my Niva for a good three years or so now, but it took this long for me to hunker down and just do it. Fortunately I already had many if not all of the major parts readily available to me, and the up-pipe I had made for the original project was still good, although it had to be modified. On this page I'll go into a brief explanation of turbocharging theory, followed by an idea of what my original plan was and how it is different from what I decided to do now.
-Turbo Theory
-As we all know, the amount of power an engine produces is directly proportional to the amount of air it can pump, the more air you can get into the engine, either by having 4 valves per cylinder, an agressive cam, or with larger displacement, the more fuel can be added and the more power can be generated. There is another way to get more air molecules into a motor, and that is to increase the pressure of the air entering the engine. Turbocharging and supercharging are ways of compressing the incoming air to increase the amount of air molecules introduced to the cylinders. In a turbocharger, exhaust gases are used to spin a turbine (mini propellor) the turbine is connected to a shaft which is in turn connected to a centrifugal compressor, basically another fan that spins air at high speeds, flinging it into the sides of the compressor housing where centrifugal force is converted into pressure. This pressurized air is then introduced to the cylinder with additional fuel where it can produce much higher cylinder pressures (resulting in more power!). The following graphic (courtesy of Garrett) shows a simple functional diagram of a turbocharger and engine.
-The Old Project vs. Reality
-My original plan was to run a 1.6L engine (thanks to it's lower compression), with intercooling and to build myself a custom intake manifold and multi point fuel injection system. Instead, with the original plan dragging along and not getting anything done, I decided it was time I just got right down to it and installed the turbo on my current daily driver. In this case the Niva was my 1995 "Aylmer", and it already had a bumped up compression ratio thanks to head shaving (~10.5:1). I would not intercool and use the stock fuel injection setup but aided by extra enrichment of some kind. Follow the links below to find not only the first two attempt at turbo-ing engines, but the current functional version and the problems associated. You can also find an interesting magazine article (in French) of a prototype turboed Niva.
