Changing out 5.0 vortec for 5.7 vortec?

[1968 Pontiac]

I have a 98 C1500 with 5.0 engine. I'm thinking of swapping that out for a 5.7. I'm wondering if I also have to switch the computer, or can I just re-program it for the 5.7? Thanks.

[Jeremy-WI]

Something would have to be done with the computer. THe injector pulse would be a little bit longer for the 5.7 and possibly some other sensors would have different readings. Here's the real difference(kind of odd), the 5.0 and 5.7 had different exhaust systems, the 5.0 had a single cat and the 5.7 had a dual cat and the O2 locations are different. The easiest would be if you had the exhaust and the computer from the 5.7 and hopefully the 5.7 donor had the same gear ratio

[1968 Pontiac]

Mmmmm, so do the 5.7's have dual exhaust or just two cat's in a single exhaust?

I keep hoping that something will be as easy sixties and early seventies vehicles

[Jeremy-WI]

It has parallel cats where bank 1 and bank 2 are seperate, been a while so I am not sure if it combines after the cats into one muffler. I know its not like some of the ford trucks that had two cats in series. I am sure the 350 pcm would work with true dual exhaust as long as the O2 sensor locations are not changed dramatically