Those actually arent bad times for the mods really, for an AOD car anyway.
Yes they are.
My '88 AOD car went 14.7 @ 93MPH bone stock with 2.73's. This was leaving it in Drive too.
89MPH trap speed is way too low. It suggests you are losing HP somewhere. However, shifting at 3000RPM is way too low. Your TV cable prob needs to be adjusted. Try the 1-D-1 shuffler and see if you can get your trap MPH up around 91-94MPH. That would be a better indicator if the car is making the power it should.
WTF! I ran I 14.2 with my 5speed and some basic mods at 95mph.

Took the stang to the track tonight, was definately slow LOL.
It is an 89 LX with an AOD, has Flowmaster dumps, ford racing wires, msd coil and distributer cap, timing bumped to 14degrees and a K&N cone filter. I know not very many mods but I pretty much just got the car.
Anyway the two runs I made looked like this:
Run 1
60ft- 2.37
330ft- 6.63
1/8th et- 10.16
1/8th mph- 69.58
1/4 et- 15.76
1/4 mph- 87.14
Run 2
60ft- 2.35
330ft- 6.62
1/8th et- 10.15
1/8th mph- 69.44
1/4 et- 15.76
1/4 mph- 86.97
Should the car be faster than this?
Well, even with a stock car you should be able to get your 60 foot times down to at least a 2.0, even on street tires...just takes a lot of practice. That alone will get your time down a lot. Then, are you doing the 1-2-1 AOD shuffle? This is where, when it's time to shift into 2nd, you slip it into second and immediately back into 1st..this will shift you into 2nd but it won't automatically shift into 3rd/OD on its own until you shift back into 2nd. It's a little hard on the trany but that'll really improve your times. I'd say being a stockish AOD, high 14s are what you can expect.