Might help if you stated which motor you had...but it probably doesn't matter. Unless you have a turbo, the 3" pipe will be a bad idea that will hurt your bottom end power. Conventional wisdom is that a 22R or 22RE does best with 2.25" pipes. Not sure on the best for the 3.0 V6, but it's probably around 2.25"/side.

FWIW, the 22RTE does very well with 3" pipes.

-Jeff

Jeff Moskovitz
1986 turbo 4X4 truck
1998 2.7L/M5 4X4 4Runner

Jeff's 22R-TE page

22RTE Turbo Truck Forum (advertising free)