1/4 timeslip :( What can I do???

[Sonics2042]

Hello,

Here is my info:
r/t: .929
60': 2.380
330: 6.783
1/8: 10.271
MPH: 70.64
1000 13.253
1/4: 15.79
MPH: 88.41

In my car's defense it was about 85 degrees out and I think it was probably 500-1000 feet up. Also there are two sensors on my computer that are shot. One is the one that has something to do with giving exhaust gases. I was told I was losing 10 HP from that one. The other is one that is causing my engine to hesitate.

My car is totally stock. I am wondering what it would have run under better conditions (50 degrees out and both sensors fixed), and better launch.

Also how will the following mods help:
3.73 gears
2.5" MAC exhaust.
2.5" MAC Long Equal Length headers.
2.5" MAC H-pipe with cats (I think it is 2.5")
MAC Intake (the one that mounts in fender wall.
Possibly a chip (I have AOD)

What can to gain from these mods, and what will they take from my time? (Under ideal conditions...)

Thanks,
DoranW