Foxbuilder is correct.
If you decide to build a torquey engine, here are some options:
A stroker kit for your 302 (317,331,347,etc.)
A stroked 351W (393,420,427)
A roots type/twin screw supercharger like a Kenne Bell will make a lot of lowend torque, but basically even a centrifugal supercharger will give you tons of torque.
Good heads are a must as well because the stock heads aren't very good for anything above stock.
Getting traction should also be a top priority because power is useless if you don't put it to the ground. Getting sticky tires, compliant suspension, stiffer control arms (tubular w/polyeurethane bushings).
You'll also want to get subframe connectors (weld in, full length) because it will keep your chassis from flexing which will result in more even launches, better handling and feel.
A engine designed for lowend torque will more power in lower rpm's and will be able to cruise at lower rpm's but will have less gears to multiply the torque in a racing situation (if you stay with stock gears), but you'll also have tons of torque whenever you step on the gas.
If you build up a high-rpm 302 it won't suck as much gas (unless you get really steep gears) and you won't have the torque all in one area so you'll actually have a chance at controlling the tires before the powerband kicks in, but on the otherhand if you do decide to gear it high, you'll have the stress of running high RPM's quite a bit.
Either way, your mustang will scream and command attention and spectators to look at your beatiful tail lights. Good luck,
feel free to ask anymore questions.
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Mustang Parts Specialties ripped me off, it could happen to you as well.
'84 Mustang 5.0 LX
my LX
'89 Mustang GT
my GT