so I have a 1997 grand Prix gtp, ive had it for while now but when i first bought i drove it probably about 40 miles home, got a mile away from my house and the tranny went out. I bought a used transmission with 60,000 miles drove the car for a week and the tranny went out again. i absoutley love the car it was fast as ****. so time has come around and im thinking about putting another transmission in it that i found for $150 yes or no? do you think i should stick another stock tranny in it or is there anything i could do to the tranny to beef it up a little bit. also the guy has an xp cam and is3 cam headers. but i think he may have sold the headers but if so can i still install the cam or does it have to have headers and is the xp cam any good? he also had 3.4 press on pulleys should i install them with out anything being done and if i do how much of a difference will my car have in power/ect or what kind of difference will it make. and the last thing he also dhp tune he say he can amp my car to a 1.0 or 1.2 dhp file is it safe to do and what kind of difference will it make? thanks responders