hi, i have a 1991 gmc jimmy. it has a 4.3l fuel injected v6 in it. its a 2 door 4x4. i was wondering how i could get more power from my car without spending tons of money. like i dont want to buy a new engine or tranny or something like that, i just want some more power out of it. also i was wondering what is the biggest size tire this truck could handle? right now i have 205's on it. i was going to buy 225's but then a friend said that my engine wasn't big enough to handle those size of tires and that my truck couldn't handle it. is that true? could my truck handle 225's? or should i get 215's? thanks for all your help!!!