Start with what the Alpina D4 is: a car with diesel engine, from Alpina. What it meant takes a little longer.
Under the skin
The engine is diesel engine. These are manufacturer figures carried by Wikipedia and Wikidata, not road-test measurements.
In context
Nearby in the Alpina catalogue sit the Alpina B10 and the Alpina B10 (E39).
The record
The open record for the Alpina D4 carries no verified engine, output, weight or price yet. MotorJury does not fill gaps with guesses; this entry gives the model a home in the catalogue and grows as sourced specifications and photographs arrive. Corrections: corrections@motorjury.com.