What is the HP increase when adding JBA Headers +JBA Cat-back Exhaust to a Supercharged Tacoma?

A guy local to me is selling a brand new set of JBA Headers and JBA Cat-back exhaust. My 04 Tacoma is already supercharged w/ 7th injector, so was wondering what the HP increase would be adding these two additional exhaust features?

Has someone out there ran a dyno on this? I have read that headers and cat-back alone isn't much of an improvement, so was wondering if it's worth when combined with a SC?

 

The gain is more impressive when measured in Mall crawler Horse power numbers.

Unless your all ready using a High Flow Cat or Cats before and after might not gain you anything if at all .

Then your back to your heads have they been worked to get benefit from a high flow exhaust ?

 

Save that money for a standalone ECU. Your truck will truly wake up then.

 

I did a before and after dyno with Doug Thorley headers ,
Was 10hp and 14 lbs torque if I remember correctly