IMHO, first up I would get myself a decent set of headers, sport cat, (or decat if allowed) dump the gas into a nicely bent up system, don't be tempted to go super size, it's not efficient stay around 2.5 to 2.75 diameter, if it was a V8 huffing shed loads I'd say 3 inches plus, but not for this. Keep it tight. Getting fast road cams would be great but If the engine can't breath properly they are wasted OK. A remap is essential as previously stated, and get a quality high flow air filter. At this point don't waste money on an induction kit, not really required.
Once you have this running sweet you'll be surprised. And if you want to go forced induction, forget the turbo, look towards a supercharger, for one, when the bonnets open, it looks hot and sexy, but as you are running a mini truck the low down grunt will be phenomenal, you will get near full boost from idle, and that coupled to a tricked up auto trans will give some serious torque, which is what you asked for. A step further would be twin charging to provide some serious top end power but it is quite complex and requires very very deep pockets and lots of serious work.
Forced induction with high boost pressures requires lowering your compression ratio, and additional hardware, at this stage you might as well throw caution to the wind and fit forged pistons, and this opens the flood grates for heavy duty rods, rebalancing, gas flowing heads, and so it goes, because once you start, at no point is there a cut off until the whole motor is spot on, or there is no point.
Keep it easy, keep it within reach and enjoy. Unless you have thousands of disposable income.... Mmm those were the days.... 9 second quarter miles.... Enjoy.