I've been squeezing what I can out of this one without doing major engine work. No headers available, no cams, no perf. clutchin other words, very little aftermarket support. So far, I have replaced the obnoxious fan clutch with dual electric 14" fans, added a conical air filter, removed the intake resonator, had muffler shop remove muffler and resonator and replace with a single glass pack, upgraded wires and plugs, running full synthetic mobil 1 motor oil. And ofcourse, she's on a strict diet of premium only exxon fuel, despite fuel prices.
By the way she drives now, I am sure I am well over the stock 121hp thats rated for this 2.6L...
Now I am thinking about doing a "brand loyal" swap to a 3.0L V6 DOHC that was in the '91 Mazda 929S. That one pushes right around 195hp stock. With the same "tweaking" that I've done to my 2.6L, I'm sure I can pass the 200hp mark, which should keep me happy long enough to figure out how to put a late model V6 pushing 300hp, like the duratech or cyclone engines being used by ford and mazda now.