Aeroforce scan gauge can be bought.
Throwing a smaller pulley on your car is like banging a stripper and hoping not catch anything. You could do it but you run the risk of it knocking and eventually causing you to chip a piston which of course going to require a rebuild or another motor. In my opinion if your serious about modding you need to invest in something to scan the car with. Or just leave the stock 3.8 on until then.
Probably not what you want to hear but it's about doing it safely and minimizing the risk of any damage.
