Thinking about buying a Apexi N1 Exhaust

[J-Syght]

I was thinking about buying a Apexi N1 Exhaust but I was wondering about how many HP will I gain with a stock 99 GST with just a K&N FIPK Filter, & some race plugs & Wirres?

 

[Smoothie97]

Probably around 5-10 HP.

 

[97_GSXTC]

i just intalled an N1, with no other mods to my GSX. i noticed it just helps me get to 3k rpm quiker so my lag is a little less. but hp numbers tho, im not sure, can only say by the seat of the pants feel i guess.

 

[got_no_sol]

If I were you I wouldn't spend your money on the catback, I just spent 490$ to get 3 inch all the way back on my car....

if you want info, pm me