well the 3.1 runs excellent so i cannot bring myself to pull it... not for a while. when the day does come that it tires out the 3400 would be the next logical step. i just wondered about the particulars of that swap. is it possible to install that engine and use stock electronics with larger fuel injectors. i did a similar type of swap with a 1989 camaro, i pulled a 305 tbi and put a 350 in its place. i had to swap with a 350 chip, knock senor, and fuel pump. the end result was a 350 that ran extremely well in a car that never came with a 350 tbi stock from the factory. is it possible to do the same kind of swap with our cars or do you have to move to an OBDII computer and all of the wirring? does the engine go physicall into the car the same way the 3.1 does with all of the same mounts? how do these cars run with a 3400 instead of a 3.1? the 3400 is the engine used in the grand am GT, the grand am GT does 0-60 in 7.8 seconds, our cars are significantly lighter about 500 lbs less so i can imagine with the weight loss performance must go up. what do they do 0-60 in with a 3400 in a 1991 cavalier convertible?
All these questions have been answered tons of times. It's pretty much a direct fit using sensors off the 31 and one custom bracket. Search around and you'll find all the info you need. Also search at V6Z24.com and 60degreev6.com.