best ecu

Discussion in 'Fox 5.0 Mustang Tech' started by Doc90, Aug 16, 2006.

  1. i need to get a new ecu i have 1990 notch and i need to know what ecu i need it is a 5.0, 5speed, i know that there are a bunch a9l, a9m i dont really know which is the best.
  2. If your car is a 90 manual then the stock one should be an A9L. I would think that this would be the best since thats what it had. However I have heard that the auto computer (A9P) had a little bit different timing/fuel curve table because of the auto tranny to keep the HP numbers up a little bit. Not for sure if this is true or not.
  3. Using the TwEECer to compare the A9L and A9P Sealevel Spark Tables, it does appear that the A9P has significantly more timing at high loads.

    The A9L seems to have more timing in the lower loads however.

    Many folks have converted to the X3Z computer from a 93 Cobra, but there is no real power advantage there. The X3Z requires a MAF modification as well.

    Stick with the A9* computers.

  4. auto computer will run a 5 speed car just fine and many prefer it, however a auto car must have the auto computer
  5. I dont how this Auto computer stuff works exsactly internally. But I put A speed density computer thats was out of a standred car into a 5.0 aod toyota conversion. And i was worried about it not working But it runns just like Pony. And i was looking at the wiring digramps and it jsut looks to me all that really is diffrent is the Clutch switch, or netural safty switch.

    I aslo put a auto comp(A9p) into a 93 ford f150, with Mustang T-5 tranny

    I wish some one could explain why it "shouldnt" work.
  6. I'm not really sure what you are asking?

    Your A9P wouldn't have any trouble with the manual F150

    I assume your toyota conversion was SD?

    What cannot be done is to run an Automatic Transmission with a Manual computer.