Depending on what you are doing with the car will be the key. It sounds like you use it mostly for street use with worrying about emmissions and things. In my opinion I would just get some shorties with an O/R x pipe. Then when you have to go to emmissions put you stock h-pipe back on. That is if you have head work done to your car. If not stick with the stock headers and x-pipe and you will get more power.
89sleeper said:
What's this slower business? I've never heard of not taking off the stock headers without getting new heads (or otherwise work done)... it helped me and my 5 other friends without any head work...
I've heard that 3" inch all the way back will give you less torque at the low end, but thos stock headers are constricting as pooh. Is it along the same principle as this?
I have seen tests on all the major header manufacturers stuff. They compared LT, shorties, and stock headers on a stock engine. They were all very close. There are minimal peak HP and TQ gains to be had, but they are really not worth the time and $ to install new headers. Although they look really ugly and pinched off, they do flow quite good. I have done no independant testing, this is just what my internet research turned up when I was considering a header purchase. Mine are still stock.
I would say getting gears, depending on what you have out back now, will give you the best bang for the buck (read more accelerative feel). Way more than headers, cold air intake and throttle body combined. It doesn't "give" more power, it just makes it easier for the motor to move the car, so acceleration is faster. The downside is that the rpm range in which the car runs at a given mph will be higher, possible lower mileage, and slightly lower top speed. Getting an O/R pipe and better flowing pipes will add a lot to the driving experience...you can't beat the growl at low rpms and wail at WOT. It will make you feel like you are flying, trust you me lol.