24lb injectors, I NEED clarification please!

Discussion in 'Fox 5.0 Mustang Tech' started by stykthyn, Dec 25, 2007.

  1. I recently acquired a set of 24lb injectors from a MarkVIII. I want to use these on the engine that I am currently building. my question is , do I need a cobra ECU? or do I need a calibrated MAF?

    I have been doing a lot of research and it the concencus seems 50/50.
    I keep reading it is not the maf it is the ECU that is calibrated for the injectors.
    then I read about someone else that runs a "calibrated" MAF and has no issues whatsoever.
    I dont want to run a cobra ECU b/c I have heard that they are garbage and will slow a car down, that the stock HO ECU is much better. Is a tune basically what is required? If all I need is a tune, will a tweecer handle the job?

    sorry to post such noob questions, but there is a lot of contradictory advice out there on this subject.
  2. I've spent a lot of years reading the tune vs. "calibrated" MAF meter debate. A tune is almost 100% reliable for setting up 24# with the A9L computer. It can be expensive to have done however.

    I see a whole lot of conflicting data concerning the cal'd MAFs though. You can take 2 cars that are almost identical and they will both react completely different with the same exact cal'd MAF. One car will have problems that are seemingly incurable and the next car runs great.

    I believe that a lot of the problems with cal'd MAFs aren't really problems with the MAFs. Even the C&L. I think that if a person were to dig into the cars that are having problems then they would find bad connections, grounds and other sensors.

    I'm getting ready to put my HCI project together with 24# injectors and a MAC MAF. I think the MAC unit is really just a C&L. We shall see. It was only $95 brand new so I'm not looseing much by trying.
  3. post up what you find out when you get it all done.
  4. The X3Z doesn't give up the much compared to an A9* ecu.

    The advantage of the X3Z is STOCK driveability with 24's.
  5. cobra ecm is calibrated for 24s. The disadvantage to the cobra ecm(x3z) is that it pulls timing out at 90mph. So if you plan to take it to the track by a pro-m or c&l that is made for 24s and use the a9l.
  6. it's a street and auto-x only, and will rarely if ever see speeds over 75-80, will the cobra ECU work well with this? my combo is pretty close to stock cobra. gt40's, tmoss lower, and a tfs-1 cam.
  7. Yeah a cobra ecm will work great for that combo. Should be tapin in on 12s too!
  8. How does the ecu get the mph reading?
    What table is this done in?

  9. I have no clue. That info was straight out of one of the books. Hi-po ford fuel inj. iirc. It is true by the way it shows on dyno. Honestly my favorite ecm is a9p. The auto ecm has a more aggressive timing table.
  10. Would you mind double checking the book title?

    The A9P has .5 to 1 degree more timing at WOT... (with the exception of between 1k to 1,600rpm)
    There is a page on my site (see sig for link) that compares the tables...