Funky Tune Issues

Discussion in 'Build Ups & Projects' started by Vettn71, Jul 28, 2015.

  1. Vettn71

    Vettn71 Member

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    Have my 96 GT at a local tuner, who is well known for tuning Mustangs. I had 30lb injectors in it and it made pretty decent power (364). The car wouldnt idle when coming to a stop light, hut would drop and die. It would start right back up, and idle perfectly. I put in 19lb injectors to see how that would affdct things and it idles perfectly, but is way down on power (30hp). The tuner doesnt quite understand why there would be such a power loss. Right now hes considering going back to the e0lb injectors, but i cant drive this thing having to feather the gas every time i stop.

    Any ideas?

    TIA
    Jim
     
  2. Vettn71

    Vettn71 Member

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    BTW, i just recently purchased this car from a forum member. I havent been able to drive it, mostly due to it sitting at this shop. Its a 5 speed, forged, stroked, PI heads, Crower Stage 2 cams. It has some piston slap on start up, which should not be an issue. It also has a 195 l/hr fuel pump, 75mm BBK throttle body and a C&L plenum. The exhaust headers (LT) are not a good quality, but would not impact the idle quality. It has high flow cats, with the rear O2 sensors turned off. The fact it idles well with the 19s, but not with the 30s just seems odd.

    Jim
     
  3. lwarrior1016

    lwarrior1016 Moderator Staff SN95 Supporter

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    What kind of 30's are they? Are they ford p/n'd 30's or are they an off brand? A lot of the injectors ability directly reflects who makes it. If they are cheapo eBay injectors then that could be your problem.
     
  4. Vettn71

    Vettn71 Member

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    Not cheap. They were in my sons 347 and had no issues. Wish it were that simple. The afr seems right on. Theres parallel issues; the inability to idle down without stalling first (30s) and the massive reduction in power (19s).

    Thanks
    Jim