can i put 24 valve injectors in a 12 valve head??

 

I'm pretty sure you can. but you cannot swap HPCR injectors.

 

what are hpcr injectors

 

High Pressure Common Rail (HPCR)

That's on the '03+ engines.

 

02 and earlier injectors are 'jerk' style. they fire from the pressure generated bu the pump. normaly around 5-6000 PSI

the HPCR injectors are electronicaly fired like solenoids. the pressure in the rail can sometimes be as high as 20-24,000 PSI. 3-4X the pressure of the previous models