I believe the stock injectors are 4 pintle but they are in the old injector body style. There are people who have deleted the vacuum lines and seen no difference in fuel economy which leads me to believe it may have just been incorporated to help reduce emissions or something.
The main issue with the stock injectors is that they are shorter than the standard size, VAC makes an adapter to use regular size injectors in the M42/44.
https://store.vacmotorsports.com/vac...ors-p2454.aspx