Cfm-tech.com and tbichips.com have lots of good info for you to study up on! I bought almost everything that cfm technologies offers for our trucks and have no regrets. Ryoken is right, a heated O2 sensor is a must if you go with those long tube headers. I'm personally still running the stock manifolds and y pipe into a 3" magnaflow straight thru catalytic converter and a Flowmaster 3" catback exhaust kit I bought at Summit. It's too loud In my opinion, but I'm getting old I guess. I really like CFM's throttle body spacer over the other manufacturers, because it allows the intake to draw air/fuel mixture from both bores of the throttle body, however it's almost $40 more, but I really liked their design and the quality of the part. Many guys on here have had good results by bumping up their fuel pressure as well. If you have any more questions ask away, and yes the $25 for full access to this site is well worth it, and you will get it back in savings in repairs easily!!! Lots of knowledgable guys on here!!!!