As has been rightly pointed out, the TDi on the Octy stands for Turbo Direct Injection, a moniker that became famous with the Golf 1.9 TDi when it was first launched. as far as i know VW even has a Trade mark on it. the tata TDi stands for turbo diesel intercooled.
as far as the 1.9 octy is concerned, it has electronically aided direct injection(Bosch's famous VP-37 pump) and a VGT...thats what contributes to the famous turbo sound and the smooth transient response...
IDI engines allow diesels to rev to higher speeds and were very popular alternatives to DI engines for pass car applications. But they also have much higher emissions and cannot achieve certification beyond BSIII. This problem has now been solved by the use of HSDI(High speed direct injection) and CRDI engines. Modern turbo diesels with a gen II/gen III CRDI/PD systems and VGTs(variable geo. turbos) have high rated speeds, stupendous low end torque(the beemer 330d has more torque than a m3) and excellent transient driveability. they are also durable, as proved by the Audi R10 turbodiesel (5.5 L V12 twin turbodiesel, 650 HP, 811 lb-ft of torque) in the 12 hrs of sebring endurance on march 18th.
BTW how do you guys get all this info on TML projects????  |