The VW double spring injectors do not have larger internal volume, sorry for the misunderstanding. The nozzles have to be replaced in the original VW ones by 265 or 261 nozzles (used in 60x engines).Advantage: Way smoother, diesel-like start with wvo, less smoke.They should not be used with the original 308 nozzles because those will eat up the pre glow sticks. VW does not use the pre chamber system with the ball.The part number is: VW 028 130 201B or BOSCH 2FH KCA 27 S 77The engine is 1.9 TurboDiesel (not TDI) engine AAZ. IIRC, from 92-93.Tom