I am thinking about this swap into my 89 RS. Right now it has a LO3 and a A/T 700R4. i do not want to deal with changing tranny's (fresh rebuild w/ transgo shift kit) Will the LT1 bolt up to my stock 700R4? also what other mods would there have to be made the the LT1 wiring harness in order to complete the swap?? I am aware that i would need a custom ecm to fit my 89 electronics but also adapting to the new LT1, wiring, ect... let me know of any links, info, or whatever!!

thanks
dillon

 

the wiring shouldn't be too difficult. the only real problem I can think of right now is the speedo.
You will need to have the PCM from the LT1 reprogrammed with the VATS/Passkey disabled, otherwise the engine will not start.

I am doing this very swap myself right now, so I am asking a lot of questions as well. I plan on getting mine down in less than a month.

I went from Carb to TPI and now to LT1.

 

The 700 will bolt up, but unless the LT1's a 92-93, the PCM is expecting a 4L60E to be there. Obviously, it won't plug in.