Mo pawah! (more power)

3vze... I'm gonna do the headers for a bit more go but I'm wondering if boring the cylinders, say, .030 over would make a significant enough improvement to make it worth the machine shop cost.

 

boring the cylinder size a few thousandths, makes an insignificant change in hp
changing compression ratio is where you get real measurable power from
changing timing is where you get real measurable power from

 

You want more power, swap it for a 3.4.

 

I would try to consider what head modifications might be made for more compression and better breathing. I am without out a clue, but that is where I would concentrate my efforts. As for me, I recently checked the valves when I was replacing the valve cover gaskets. All of the exhaust valves were out of spec, and the #6 exhaust valve clearance was unmeasurable with a 0.015" feeler gauge. Maybe it's in my head, but getting the valves back into spec seems to have helped my car pull the trailer through the mountains with a bit more strength.