How many horseies came with the stock 99 5.3L was it at 285 yet?

Also what do you think it would be at after 1 chamber flows and hypertech?

 

In 99 the 5.3 was 270hp. It wasn't until 2000 when it was 285.

 

270hp for the 99. 5.3's came with 285 in 200 and after.
Depending on your budget, if you don't have a locking diff, get one. If you do already, then go with an air intake.

 

Well I have the ol'G80 so yes I have a locker just not the best.
How much Hp will the intake add?

 

i am going to have to venture and say 5-8 HP for air intake. chime in here if i am wrong. with exhaust and HPP3, maybe you got 10-15 HP. again i am assuming these #'s. someone else might have dyno facts to share with ya instead