Depends on what year you'll be looking at, and what your idea of cheap is.
94-95 had 145hp.
96-98 had 150hp.
99-02 had 190hp.
03-04 had 193hp.
The latter two might be a decent match for a completely stock Fox Body, but they've got the benefit of being lighter, and they have a higher torque rating.
Things like a cold air intake might add a few more to those to put them around 200hp, or about 175rwhp if you have a manual, an automatic will lose a little more to the wheels.
At that point, a Nitrous kit set for 50-75hp would make it a race coming down to the driver with 94-98 GT's which weigh the same. The Foxbody would be close, again with its torque and their weight giving it a slight advantage. 99-04 GT's have 260hp, and the 05-09 GT's have 300hp. Cobras are still going to be out of reach, but maybe you could catch one napping or spinning the hell out of their tires.
Really?
Well, I said completely stock... good luck finding one.
That, and the carbed 79-85's had like 165hp.
He did say cheapI'd get a blower kit and some gaskets,injectors and MAF sensor for the ultimate power upgrade (besides nitrous).
He did say cheap
I've seen a couple of supercharged v6's that put rather respectable dyno numbers down, but if you're limited on funds, it's hard to argue with nitrous.
I can see where a Suburban with a V8 would be able to take a V6 Mustang.. at least there are some vehicles that a V6 Mustang can take. On the way to work I had to educate the driver of a Honda Pilot that a black paint job and new car smell does not make him faster than a Mustang. (I think it was a Pilot.. they all kinda look the same to me) Anyway, this guy was a slow learner. It took three stoplights for him to learn his lesson. I didn't bother to tell him that his shiny new rig got beat 3 times in a row by a 150,000 mile, twice-wrecked, automatic Mustang with the air conditioning running.
-DISCLAIMER- I am in no way advocating street racing, as it clearly states in the street racing sticky: "Street racing is not condoned here and arranging illegal activities on this board is not permitted."
We were very safe, and we were the only ones on the road in both directions. I'm just telling you of a little schooling I had to do!