Bone stock with less than 100,000 miles as long as it had good compression, I've been always been able to do that or a few tenths better. I've had a dozen or so 5.0's, I wouldn't go near a vert. or AOD if you paid me. In a fox body of course, I amazes me how good the new automatics are, being able to run as fast or faster than the 5 speed GT's. Bone stock before I did anything I've always been able to run between 14.30's and 14.50's.
And it was called the MM&FF 5 min tune up, by Even Smith. I had multiple LX and GT's (I found the LX's had about one or two tenths advantage from weight savings) I would always spend a few months trying to see how fast I could go with a stock car before I would start modifying it. I'd always use a positive stop shifter, (I learned really quick that if you didn't have one, bending the shifter forks and ruining a perfectly good T5 wouldn't take long at all). I would set the timing to 16 degrees, screen taken out of the MAS, removed silencer on the air filter, removed or used a
K&N filter, set the TPS voltage set to 5 volts, use any kind of elec. fan to get rid of that clutch fan, 160 degree thermostat or none depending on if you wanted heat or not, (without one you could cool off the motor a lot faster between runs), or you could used a reducer spacer that had a smaller hole in it. I'd use a phenolic intake spacer so when you used ice to cool the intake it wouldn't heat back up immediately, a small water hose to reroute water around the throttle body spacer, no coolent with water wetter (you're not supposed to used coolent on a dragstrip anyway), removed front sway bar, and everything else inside the car like the spare tire and jack, pumped up front tires and usually the stock rear tires but if I ever had to replace the rears and hadn't started using drag radials yet I would put a little bigger tire on the back like a 255/60/15 or 255/50/16 seemed to work good. I would ice the intake for 15 mins before the next run and make sure I didn't get melted water on the bottom intake that would get under the rear tires I'd use a 44 inch short belt that bypassed everything except for the water pump and alternator. And perfected my launch and 250 rpm power shifts. With those things done, I had no problems running 13.50's to 13.70's. I had a hard time getting street races because everyone thought I was hiding nitrous somewhere. Then with 3.73's and 26x10 MT's on stock wheels, I would come very close to running 12's. They would always give me 5-6 tenths. It was amazing how much money you could make back in the day on Fri and Sat nights running against guys with stock looking Mustangs that just didn't put in the time or effort to test and tune their car to see how fast they could go stock. So many people would just buy a 5.0, take it out to the race hangouts without doing anything then accuse me of lying or hiding nitrous. Taking off a second from dead stock wasn't hard at all if you knew what you were doing and took the time to get there.