It takes a “gearhead” to follow all the various fuel injection systems; TBI – Throttle Body Injection, TPI – Tuned Port Injection, GDI – Gasoline Direct Injection, TDI – Turbo Direct Injection (diesel), two stroke direct injection (both gasoline and diesel), and for the sake of tradition, even two stroke Roots blower and turbo diesels such as the infamous GMC 6-71 of WWII fame.
As a confirmed gearhead, I believe the most significant modern era advance in fuel injection is the digital computer receiving constant information about the exhaust gasses and engine status which enable adjusting fuel input accordingly. Slapping a digital computer on a fuel injection system is comparatively inexpensive, flexible, adjustable (chips), and repairable (reliable).
The TBI – Throttle Body Injection gasoline motors are fairly primitive by current standards for electronically controlled engines but they are really excellent engines for off road use because they are relatively simple and offer anyone willing to learn about them the ability to make repairs in remote locals.
As stated above by ntsqd and Herr42, the V8 examples of old TBI engines have only two fuel injectors. About the only thing that ever goes wrong with them is a vacuum leak. It is practical to carry a complete duplicate set of components for these simpler fuel systems in a repair kit. The TBI engines should not be dismissed by off roaders. These engines do a nice job in the low RPM ranges and they last a long time. The famous guy who drove his old Chevy pickup a million miles without an engine teardown had a TBI engine in his truck.
Diesel engines are very different animals from gasoline engines. Basically, diesel engines run by creating explosions in their cylinders whereas gasoline engines create flame fronts in their cylinders as fuel is “burned” and not detonated.
Maybe this is not the place for technical discussions about diesel vs. gasoline engines. Digital computers have enabled gasoline engines to almost catch up with diesels in terms of efficiency. Due to the significant extra cost of diesel engines and diesel fuel in the United States, diesels have lost their advantage at present. If the Big Three is to successfully market half ton light trucks with diesel engines, the cost of diesel fuel MUST come down relative to gasoline.
