GM-GMC: 1999 gmc sierra 4.3 liter, gmc sierra, stock exhaust

Question
I'm am going to put some performance mods on to increase power.  I am looking at headers and I would like to know if I have air injection or not?  I am also putting in and air intake kit, will these two mods be worth anything with out doing the entire exhaust?

Thanks,

Eric

Answer
in order to find out if this vehicle has air you will have to call or e mail gmc by going to gmc.com

ask them to forward this question to information station they can answer this if you have any trouble let me know.

they can only answer about the air

air intake will improve some of the performance but with the stock exhaust you are not going to get much improvement

these questions i would take to a performance site and post on thier boards for others who have done the same to give insite.