How many have headers only?

I have a 99 TA and I was thinking about getting myself longtube headers and catted ypipe for Xmas. I have the K&N filter,And lid , plus all the little mods that I could do.I will be getting a stall later, but I think that maybe as far as I go, but I will be getting a tune also. I know I will see some power added with just these things done? but how much?

You get a lid, GOOD LTs, 3" y-pipe, and a catback. You could see 30-40rwhp or 330-340rwhp.

All depends on how good your car is running and if it's an automatic or m6. M6 will make more power.