if the 3400 top end will fit on the 3100 bottom end will the 3100 top end fit on the 3400 bottom end? reason being i know a guy who blew the bottom end out of his 97 grand am, and i have the bottom end of a 3400 sitting here and if he can use it then its a benifit for both of us, i can get rid of the bottom end and he can get his car running again
My 3400 Swap Page
I wouldnt do that if he is your friend.
I have never heard of any one going with a smaller top end, even in v-8 stuff. always bigger.
Its kind of like if you ran a mile while breathing through a straw. Wouldnt turn out too good.
01 cav w/01 3400 gam gt 4t45e
what would be the downsides of him doing it? hes not a friend but that dont matter im gathering info to tell him everything that i can before he picks it up, its an older guy so i dont think he will car if its not as powerfull as the 3400 he had the 3100 in there before. just figureing out if it will work before i sell it to him
My 3400 Swap Page
Before you go any further find the bore size and stroke of the 3.1 and 3.4 to see what the exact difference is and how much.
As far as I know no one has tried to make less power from a 3.4, you would be a first , if it works. The biggest question is what computer are you going to use. Really cant use the 3.1 because you changed the combustion chamber size to a larger size, If you run a larger comb chamber with the smaller injector pulse width, your going to run lean and fry a piston or two. You might be able to fool the 3.1 computer by replacing the ECT and IAT sensors with resistors to simulate colder weather to run a richer mixture, but then you run into cooling fan problems because the cooling fan uses the value of the ECT sensor to turn it on. You see you end up with a snow ball effect eventually and the person that suffers is the installer/ owner.
The guys that are using the 3.4 upper on the 3.1's are either running rich exhaust mixtures or running an aftermarket ecm. Rich mixtures arent a threat to engines like the lean scenerio that you are wanting to do.
Now I might be wrong, but this is my best guess to some of the issues that you are going to encounter. I guess you wont know for sure till you do it , and I have never heard of doing what you want to do, so lots of luck if you decide to go that route.
01 cav w/01 3400 gam gt 4t45e
The 00+ 3100 uses the same top end parts as the 3400, so it should work just fine. The extra displacement might throw the comptuer off some as Joe was saying. A better place to ask this question would be over on 60degreev6.com
