I have 2004 xr6 ford ba. I have put a 2.5 cat back exhaust system in it (cost $580), pacemaker extractors with the hi flow cat (cost $900) and a growler cold air intake(cost $500). Now I'm just hoping on some good advice on what should i do next. I was thinking of getting a ecu or tunning it. But got know idea about ecus and turning my car. I have a hi performance tachometer on me as well but people were saying that it would by know good for my xr6.

Any ideas on what I should do to my xr6 ford ba felcon

My suggestion would be to upgrade the front and rear brakes. If you want to make it go faster, might be an idea to make sure you can STOP it. The ones you need are 322mm front and 328mm rear.
You will need to buy a NEW outrigger, the part that actually bolts to the caliper and the stub axle and these can be picked up for about $100.00 a pair on Ebay. You will be able to use your front calipers that you already have but will need to change the rear ones. Of course you will need new Discs for the F&R but believe me, it will be WELL worth the money and the time and effort.

Thank you much appreciated

I just wanted to second Papa Smurf's comment about the brake upgrade. I did this a year ago and wish I had of done it sooner. Well worth it.