You know what,
I am perhaps the biggest support of the 3RZ (2.7) engine here as I have a Supercharged 2.7 in my 1981 truck, but I am gonna have to disagree with everyone else's opinion.
If you wanted to swap in the 3.0 in place of the 2.7, then I would be against it because in my opinion the 2.7 is more powerful than the 3.0. But the 3.4 is one excellent engine. You will get 19% more HP and 27% more TQ with the 3.4, but remember that you won't get the same gas mileage as you are now with the 2.7. My 2.7, Marlin's, Dean's, and Bevin's are all getting 18-21 MPG combined mileage (city and highway) so we are all really stoked with both the performance and the mileage of the 2.7.
But hey, I supercharged mine. I was looking for more power below 2500 rpm and that's what I got. Maybe you are looking for the same? I would say that rebuilding your 2.7 would be a much eaiser task, but it may also cost you about the same as a (cheap) 3.4 swap. Wiring harnesses are already available.......
Just a different view
