and the new direct injection petrol(gasoline) cars, have no T-plate, its all controlled by a computor along with chamber shape, and when the fuel is injected and volume.
a little thought here; if you understand what detonation is in a regular gas engine, its uncontolled combustion it can damage the engine. because you have a MIXTURE of fuel and air in the chamber, if conditions are not perfect, it burns all at once, very high cyl.pressures, knock and heat, could melt a piston,blow gaskets ETC.
now a D/I engine has only air in the chamber, IT CANNOT DETONATE, got no fuel in it!
and at a predetermined point of injection,in the chamber, under the computor control.
it squirts a small amount of fuel, in a specific area of the piston, sometimes the fuel is done all at once,, or in small stacatto squirts, all variable by computor.
it is such an improvement , over old school carbys, and port injection, its a different world of technology.