What headers should i get i will have them coated and they have to be emissions legal? How much power can i expect

 

I would recommend the AZ Speed and Marine if you can afford it. They're expensive, but well worth it. See sig, pretty good power too.

 

you can stay legal with long tube headers like JetHot and have the AIR/EGR and 02 hookup, still run hi-flow cats and run 02 simms after the cats. You would pass emmissions. I'm running the above setup without cats until they go to visual cat inspection here in TX and even then I'm building fake CAT shells to put over the ypipe.

Finish Line Performance makes a Longtube header that has all the emmision hookups, cats and offroad pipes. What very few will tell you is that long tube headers and CATs installed do NOT make it necessarily legal. The reason why is that the cats are too far back to heat up and effectively cannot burn up the unspent fuel/pollution. So in the older fbody's that get sniffed that could possibly be a problem and would be the reason why you failed the sniff test. I'm a 97 and do not get sniffed.

As for rear wheel hp, here is what I've learned from an analysis I done over several sites and calling numerous shops. I compiled the following data averages as follows:

Shorty's: 8-12
Midlenthgs: 12-17
LongTubes: 17-22

 

Those numbers may be a bit on the conservative side. I was only trapping about 100 in similar weather, and now after the exhaust, I'm trapping 105-106. That's a bit more than 17-20 hp, but I also did a full exhaust.

 

well what would be everything i need to do a full exhaust i want to use the slp loudmouth cat back. Im in nj so there are alot of emission restrictions.