Finally i found wut i needed to add the 20-30hp i needed without having to worry about damaging my engine!! Since the 4A-FE engine isnt a performance engine, a turbo/super charger will probably damge my 146k mileage engine. However QTEC will add about 20-30hp and its safe!! The kit for a celica is only $150 and if u need it installed my mechanic said it would cost about $120-$150 in labor. So if u have a Celica ST 1.6L and want some extra Horsepower than can easily be turned on and off get a QTEC installed!! The most it could possibly cost is $500! Here's the site i ordered mine from!!

http://www.pfyc.com/store/merchant.mv?Screen=PROD&Store_Code=PFYC&Product_Code=GN5002&Product_Count=4&Category_Code=ALEXH

Its well worth the money if you dont have a GT ,GTS or All-Trac engine.
However remember it WILL make your car VERY VERY LOUD as if i had no exhaust system in it!! But since u can turn it on and off it will give you that boost when u need it!

Any input or remarks towards this idea is welcome!

I am sure it will not add 20-30 HP to a normal daily drive car with only some bolt-on modifications, but sure it will make your car illegle and really lound when you open the y pipe.

20-30 HP is not that easy to gain, infact I don't think that's what you are looking for. I am assuming you want more torque than HP. a lot of people get mix up between the two.