24# Injectors

Discussion in '1996 - 2004 SN95 Mustang -General/Talk-' started by j966er, May 21, 2014.

  1. The builder of the performance motor I'm looking at recommends installing 24# injectors . Would I have to upgrade my fual rails an fual pump ? Also would I need to get a dyno tune or could bama write me a new tune for the hand held tuner I bought from them.
  2. 24# injectors will fit right in. You will need them either matched to your maf or have a fresh tune written
  3. I've been curious about this too...on basically stock cars, would 24lbs be any gain over stocks. Obviously a tune would be necessary, but what maf would be suitable?
  4. 24s will gain you nothing on a stock Mustang GT to even a Mustang GT with all bolt-ons. If anything, you'll run rich and lose power. I ran 24s on my all bolt-on GT and monitored the fuel through a scanner and my fuel was way rich at part throttle and WOT. So 10s are your best bet. You won't need 24s until you either have a lot more compression and/or ported heads/aftermarket cams.
  5. with either a properly calibrated maf or a tune for the injectors, the vehicle will not be rich. I will also agree that they are not needed on a bolt on car though
  6. I had a tune and my trims went super rich. I then tried 24s with a MAF sensor calibrated for them and it still went rich. Then I tried the MAF sensor and also tuned it and it was rich. Ran the 19s and it was fine. I monitored my trims in real time on a professional scanner. Even when I adjusted the fuel through my tuner it still was rich. Nothing I did with the 24s worked. And this was on a full bolt-on GT.
    trombonedemon likes this.
  7. I'm ordering 24# injectors asap I just installed patriot stage 2 heads comp 262 cams an a port matched professional products lower intake I got full bolt-ons I can hardly move my car with out it getting all choked up an starved for fuel
  8. I'm really unsure of why your builder would recommend the larger #24 injectors on an otherwise stock motor? Unless you have increased your motors need for fuel through modifications you absolutely don't need them, and there will be 0 performance gains whatsoever. The fuel system on a GT has a fair amount of growing room (bolt-ons) before you need to start seriously upgrading it. All bets are off if you decide to go forced induction because that would obviously necessitate such upgrades.
  9. Who said stock motor ? The motor I'm having built is a 3.8 block bored an stroked to 4.3 with performance, cam stage 2 ported heads an all the other good stuff that I'm to lazy to list. So this motor is fare from stock.
  10. were talking about a six banger :shrug: 19's are plenty

  11. then your tune needed adjusting. Maf transfer function was off
  12. Perhaps. Wouldn't be the weirdest thing that has happened to me...thanks for the info!
  13. Actually, I doubt that. Let's do the math.

    4.3 liters of displacement. 6000 rpm. And 100% volumetric efficiency (I could be a little over here, idk). Do the math, and it comes out to displacing around 2047 pounds of air per hour.

    Throw in a 12.5 AFR to that number, and you need 164 pounds of fuel per hour.

    Divide by 6 cylinders, and you need 27.3 pounds per hour (per hole).

    I am not at all familiar with the 6 cylinder cars, but if he can actually displace 4.3 liters, and then fill those cylinders (he did say heads and cam), then I'd recommend 30 lb/hr injectors over 24 lb/hr. My estimates are high, and 24 lb/hr would probably work. But it's significantly better to be able to inject all of the fuel needed for a given stroke in a SHORT period of time (to take advantage of the port air velocity), versus just having them run at 100% duty cycle like the 24's likely would be at higher rpm.
    trombonedemon likes this.
  14. My bad, I automatically thought it was a SOHC 2V 4.6...