Hi all, just a quick question...engine rebuild all ok apart from the boost...foot down in most gears little bit of boost but it's like fuel cut at the peak of boost..The ecu is a z4 with an unknown chip I have put yellow injectors instead of the gray one. My question will the z4 run the yellow ones without mapping? Wrx import lump with Sti tmic,td05,yellow injectors,z4 with unknown chip,standard headers,3inch up pipe,2.5inch down,nur spec r system.

 

Sounds like you answered your own question....

 

Ok...which ecu will run the yellows with above spec?

 

ESL, Alcatek, or Syvecs

 

So I need a aftermarket ecu just to run the 440s....back to grey 380s then.

 

No you need an ecu to tune your engine based on all the modifications you have.

The injectors will need mapping the same as the mods.

 

as j has said you need a to tune for your mods, just sticking a set of 440's in and hoping they work wont achieve anything and the ebay up-pipe you have fitted will only make matters worse as the bore is far to big, if you are stuck until you can get a remappable ecu refit the greys and put the original up-pipe on.