After all these mods I run 14.5?!

[SlowStang2]

This is pissing me off. My car ran a 15.2@90 stock. It got all the way down to 14.3@100 once. I have never seen it again. I finally got some heads and I am running the same lousy times. Now all things are considered. My traction has been consistently the same. If ANYTHING its suffered maybe a tenth or two AT MOST. It really isnt a problem. And weather? Hah! All my times were placed under the same temps. humidity, and ive always been at the same altitude. I've read on here with guys with convertibles running 13s and I cannot escape the mid 14s. As far as my shifting launching is concerned, its been changed constantly just to find a performance increase. I've launched higher and lower...Ive shifted higher and lower...nothing. Ive dumped so much damn money into this car and its not giving anything back. I even had the motor rebuilt recently! I run my car on the street and I own other cars that are not mustangs that are running 13s on street tires, so it IS possible to run this time on radials. I am really out of options. I figured it has to be from a bad combination or something is missing or christ i dont know. Look at my sig. and let me know. Under stangnet i reviewed the cobra intake manifold set and users have stated that having this intake must be pretty much used with a 70mm T/B. Is this true? And knowing my luck, even if it does make some sort of improvement, i doubt ill see consistent 13 times with just an extra 5mm of air. If anyone is interested in how my times had gotten better throughout the mods I've made, look at my car in user's rides. Ive lost my faith. Help me find my way.

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94' Stang GT Convertible --Cobra upper&lower, GT-40Y Turbo Swirl aluminum heads, Mac cold air w/K&N, BBK equal length shorties, BBK offroad H-pipe, American Thunder cat-back, BBK T/B 65mm, 24lb injectors, Pro-77mm MAM, pulleys, aluminum driveshaft, 3.55s, Steeda Tri-Ax shifter, adjustable fuel regulator 14.4@100 MPH on G-tech;96 at track. (Sad, i know. This is with the stock heads)