2.8 to 3.1

[1990cavz24]

I currently have a 1989 Z24 with a 2.8 V6 thats worn out and was considering a 3.1 since I have a freshly built one in my garage collecting dust. I was thinking since the 2.8 and 3.1 are pretty much the same engine except for the stroke that the computer and wiring harness I have now for the 2.8 should work fine on the 3.1 BUT some have told me that if a swap to a 3.1 that i'll need to change the computer and wiring harness in order to get it working. Can anyone here help me out before i go buying a harness and computer that I don't need.

Thanks,
Brian

[geoffinbc]

the ecm will run it fine. Hell some people have 3400 swaps running off the 2.8L ECM.

I have my 3.4L running off the 2.8L ECM in my truck. All I did was change injectors. I am sure it could be optimized a little more but it has worked great for 3 years.

[Superdave]

yep, the 2.8 ECM will run the 3.1 fine. they use the same injectors and very similar fueling.